From patchwork Sun May 21 16:04:06 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masahiro Yamada X-Patchwork-Id: 13249433 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5586DC77B73 for ; Sun, 21 May 2023 16:05:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229985AbjEUQFS (ORCPT ); Sun, 21 May 2023 12:05:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55110 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229794AbjEUQFR (ORCPT ); Sun, 21 May 2023 12:05:17 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D9E11CD; Sun, 21 May 2023 09:05:16 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 6DA8660DE9; Sun, 21 May 2023 16:05:16 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C2CA1C433EF; Sun, 21 May 2023 16:05:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1684685115; bh=kwJKTr748jqWjN1i3IcmeB/TjKVKVtw80rljWW81Xwc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NEEQFwkIadEOXado3HB0SNTEaLqMIwaCppXoh+DRHhAGrRcWp8YS0ieITv9SInVxF 4tcnvGw/Q1GNj53MG1kvTnDeMbdi8YYBWt6/3R5Oq7p2gWyMkbbtcb+rIxxR+r80E4 pgbKJMap1F9PJY5eNNtdUXBU4upOAaC3vRumR2PWhTlSsXZlyCgrIo8tGAIxQOsod/ ovEaV8/07TpLL5WOVAx/gbfaWpZaI/NJI30tBs0PZBeYql7DNEOVT1MAHCdLzd1PlU mcG8McYtC3DY3BhAWL5x7+7Qvmyy1pIYeJYcpkntSwblGybyokRozk5WrEvTgoH9oq jomqSx445Gyhw== From: Masahiro Yamada To: linux-kbuild@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Nathan Chancellor , Nick Desaulniers , Nicolas Schier , Masahiro Yamada Subject: [PATCH v6 01/20] Revert "modpost: skip ELF local symbols during section mismatch check" Date: Mon, 22 May 2023 01:04:06 +0900 Message-Id: <20230521160426.1881124-2-masahiroy@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230521160426.1881124-1-masahiroy@kernel.org> References: <20230521160426.1881124-1-masahiroy@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org This reverts commit a4d26f1a0958bb1c2b60c6f1e67c6f5d43e2647b. The variable 'fromsym' never starts with ".L" since commit 87e5b1e8f257 ("module: Sync code of is_arm_mapping_symbol()"). In other words, Pattern 6 is now dead code. Previously, the .LANCHOR1 hid the symbols listed in Pattern 2, but a4d26f1a0958 was a cheesy workaround. 87e5b1e8f257 addressed the issue in a much better way. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- scripts/mod/modpost.c | 12 ------------ 1 file changed, 12 deletions(-) diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 0d2c2aff2c03..71de14544432 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -1034,14 +1034,6 @@ static const struct sectioncheck *section_mismatch( * fromsec = text section * refsymname = *.constprop.* * - * Pattern 6: - * Hide section mismatch warnings for ELF local symbols. The goal - * is to eliminate false positive modpost warnings caused by - * compiler-generated ELF local symbol names such as ".LANCHOR1". - * Autogenerated symbol names bypass modpost's "Pattern 2" - * whitelisting, which relies on pattern-matching against symbol - * names to work. (One situation where gcc can autogenerate ELF - * local symbols is when "-fsection-anchors" is used.) **/ static int secref_whitelist(const struct sectioncheck *mismatch, const char *fromsec, const char *fromsym, @@ -1092,10 +1084,6 @@ static int secref_whitelist(const struct sectioncheck *mismatch, match(fromsym, optim_symbols)) return 0; - /* Check for pattern 6 */ - if (strstarts(fromsym, ".L")) - return 0; - return 1; } From patchwork Sun May 21 16:04:07 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masahiro Yamada X-Patchwork-Id: 13249434 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 116FDC77B7C for ; Sun, 21 May 2023 16:05:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230075AbjEUQFU (ORCPT ); Sun, 21 May 2023 12:05:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55118 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230017AbjEUQFT (ORCPT ); Sun, 21 May 2023 12:05:19 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5E1E3CD; Sun, 21 May 2023 09:05:18 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id E88F960F36; Sun, 21 May 2023 16:05:17 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 42A2BC4339E; Sun, 21 May 2023 16:05:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1684685117; bh=fNR4CDXASXYl6s1DvjTHLO1BvaWuFWmKCQClVKnCc7s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=h9MbM1JfV/RDfTfTvRsMuDs9iyR1i4Yb5uoJ/nLE4syQQxu7iQkF89kxdZiYsxWTD ZTD8cLNzJFauyIFbbMVl6tlYJpeU5kl7o+GStYWQU/u94eqU4c4bQAk2M1YrBy7jiY JLMZbn/012F3GlLcshbLfhRgjMSyvGJSIRjkIBH/tWKm+3nv469IVUcZ7iEdUoaLzv CW0Rpe7UC2E6KcTkujjKuy6x7tc5/OJfi+mW37CbhZKOZTeCZCsKo7KS0TntbvUI/y e+p0GFNB5Sofu6R+77TzNg080f2tjm3Zk2oxf8Ljr51NoZ6y8U8C/WaCcy8CRwtA5y Y/GwpNMgFlU4w== From: Masahiro Yamada To: linux-kbuild@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Nathan Chancellor , Nick Desaulniers , Nicolas Schier , Masahiro Yamada Subject: [PATCH v6 02/20] modpost: fix section mismatch message for R_ARM_ABS32 Date: Mon, 22 May 2023 01:04:07 +0900 Message-Id: <20230521160426.1881124-3-masahiroy@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230521160426.1881124-1-masahiroy@kernel.org> References: <20230521160426.1881124-1-masahiroy@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org addend_arm_rel() processes R_ARM_ABS32 in a wrong way. Here, simple test code. [test code 1] #include int __initdata foo; int get_foo(int x) { return foo; } If you compile it with ARM versatile_defconfig, modpost will show the symbol name, (unknown). WARNING: modpost: vmlinux.o: section mismatch in reference: get_foo (section: .text) -> (unknown) (section: .init.data) If you compile it for other architectures, modpost will show the correct symbol name. WARNING: modpost: vmlinux.o: section mismatch in reference: get_foo (section: .text) -> foo (section: .init.data) For R_ARM_ABS32, addend_arm_rel() sets r->r_addend to a wrong value. I just mimicked the code in arch/arm/kernel/module.c. However, there is more difficulty for ARM. Here, test code. [test code 2] #include int __initdata foo; int get_foo(int x) { return foo; } int __initdata bar; int get_bar(int x) { return bar; } With this commit applied, modpost will show the following messages for ARM versatile_defconfig: WARNING: modpost: vmlinux.o: section mismatch in reference: get_foo (section: .text) -> foo (section: .init.data) WARNING: modpost: vmlinux.o: section mismatch in reference: get_bar (section: .text) -> foo (section: .init.data) The reference from 'get_bar' to 'foo' seems wrong. I have no solution for this because it is true in assembly level. In the following output, relocation at 0x1c is no longer associated with 'bar'. The two relocation entries point to the same symbol, and the offset to 'bar' is encoded in the instruction 'r0, [r3, #4]'. Disassembly of section .text: 00000000 : 0: e59f3004 ldr r3, [pc, #4] @ c 4: e5930000 ldr r0, [r3] 8: e12fff1e bx lr c: 00000000 .word 0x00000000 00000010 : 10: e59f3004 ldr r3, [pc, #4] @ 1c 14: e5930004 ldr r0, [r3, #4] 18: e12fff1e bx lr 1c: 00000000 .word 0x00000000 Relocation section '.rel.text' at offset 0x244 contains 2 entries: Offset Info Type Sym.Value Sym. Name 0000000c 00000c02 R_ARM_ABS32 00000000 .init.data 0000001c 00000c02 R_ARM_ABS32 00000000 .init.data When find_elf_symbol() gets into a situation where relsym->st_name is zero, there is no guarantee to get the symbol name as written in C. I am keeping the current logic because it is useful in many architectures, but the symbol name is not always correct depending on the optimization of the relocation. I left some comments in find_tosym(). Fixes: 56a974fa2d59 ("kbuild: make better section mismatch reports on arm") Signed-off-by: Masahiro Yamada --- Changes in v6: - More detailed commit log scripts/mod/modpost.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 71de14544432..34fbbd85bfde 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -1124,6 +1124,10 @@ static Elf_Sym *find_tosym(struct elf_info *elf, Elf64_Sword addr, if (relsym->st_name != 0) return relsym; + /* + * Strive to find a better symbol name, but the resulting name does not + * always match the symbol referenced in the original code. + */ relsym_secindex = get_secindex(elf, relsym); for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) { if (get_secindex(elf, sym) != relsym_secindex) @@ -1306,12 +1310,12 @@ static int addend_386_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r) static int addend_arm_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r) { unsigned int r_typ = ELF_R_TYPE(r->r_info); + Elf_Sym *sym = elf->symtab_start + ELF_R_SYM(r->r_info); + unsigned int inst = TO_NATIVE(*reloc_location(elf, sechdr, r)); switch (r_typ) { case R_ARM_ABS32: - /* From ARM ABI: (S + A) | T */ - r->r_addend = (int)(long) - (elf->symtab_start + ELF_R_SYM(r->r_info)); + r->r_addend = inst + sym->st_value; break; case R_ARM_PC24: case R_ARM_CALL: From patchwork Sun May 21 16:04:08 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masahiro Yamada X-Patchwork-Id: 13249436 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 39974C77B7C for ; Sun, 21 May 2023 16:05:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229901AbjEUQFY (ORCPT ); Sun, 21 May 2023 12:05:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55132 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230153AbjEUQFV (ORCPT ); Sun, 21 May 2023 12:05:21 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5206ECD; Sun, 21 May 2023 09:05:20 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id D7A6F60FA7; Sun, 21 May 2023 16:05:19 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D86ECC433D2; Sun, 21 May 2023 16:05:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1684685119; bh=WHBV7iLszGwzqmoBiBCGvksDMYSMzg3ZUVZdErHe9Yg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jSg/z3aGOvkuyn5c5Urq2Q/TCkD0gnjBzHJ/S1qxaUK6+Fl/neoCMcMq5PMDX2t3U x9DBmCetn/NGYRUL1voVIqs4beFG+xlcjSGp79Lz+hdx+0uO+1mC+PYjv6jYLQkfnW EAOnq0H7IpKBFNsauz47zEInl1/v0r2Ng3o5w+2/USxCuOt9JCXpCWnYxMlDJlLAVn OudINlJvQf4Zpe7uXDiCMXBYD++Farbf5mi1SC7h7kBCmQJxecGbt4NuY4yAk1zoGN jHeFGEqZwxWAWyrbtkdvBXTvCiew1GQqsHcSYC2Buwx0HvDtVtXzUS0ZP9cE4Appn5 jbpzCkZPaVyzA== From: Masahiro Yamada To: linux-kbuild@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Nathan Chancellor , Nick Desaulniers , Nicolas Schier , Masahiro Yamada Subject: [PATCH v6 03/20] modpost: detect section mismatch for R_ARM_MOVW_ABS_NC and R_ARM_MOVT_ABS Date: Mon, 22 May 2023 01:04:08 +0900 Message-Id: <20230521160426.1881124-4-masahiroy@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230521160426.1881124-1-masahiroy@kernel.org> References: <20230521160426.1881124-1-masahiroy@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org ARM defconfig misses to detect some section mismatches. [test code] #include int __initdata foo; int get_foo(int x) { return foo; } It is apparently a bad reference, but modpost does not report anything for ARM defconfig (i.e. multi_v7_defconfig). The test code above produces the following relocations. Relocation section '.rel.text' at offset 0x200 contains 2 entries: Offset Info Type Sym.Value Sym. Name 00000000 0000062b R_ARM_MOVW_ABS_NC 00000000 .LANCHOR0 00000004 0000062c R_ARM_MOVT_ABS 00000000 .LANCHOR0 Relocation section '.rel.ARM.exidx' at offset 0x210 contains 2 entries: Offset Info Type Sym.Value Sym. Name 00000000 0000022a R_ARM_PREL31 00000000 .text 00000000 00001000 R_ARM_NONE 00000000 __aeabi_unwind_cpp_pr0 Currently, R_ARM_MOVW_ABS_NC and R_ARM_MOVT_ABS are just skipped. Add code to handle them. I checked arch/arm/kernel/module.c to learn how the offset is encoded in the instruction. The referenced symbol in relocation might be a local anchor. If is_valid_name() returns false, let's search for a better symbol name. Signed-off-by: Masahiro Yamada --- scripts/mod/modpost.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 34fbbd85bfde..ed2301e951a9 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -1108,7 +1108,7 @@ static inline int is_valid_name(struct elf_info *elf, Elf_Sym *sym) /** * Find symbol based on relocation record info. * In some cases the symbol supplied is a valid symbol so - * return refsym. If st_name != 0 we assume this is a valid symbol. + * return refsym. If is_valid_name() == true, we assume this is a valid symbol. * In other cases the symbol needs to be looked up in the symbol table * based on section and address. * **/ @@ -1121,7 +1121,7 @@ static Elf_Sym *find_tosym(struct elf_info *elf, Elf64_Sword addr, Elf64_Sword d; unsigned int relsym_secindex; - if (relsym->st_name != 0) + if (is_valid_name(elf, relsym)) return relsym; /* @@ -1312,11 +1312,19 @@ static int addend_arm_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r) unsigned int r_typ = ELF_R_TYPE(r->r_info); Elf_Sym *sym = elf->symtab_start + ELF_R_SYM(r->r_info); unsigned int inst = TO_NATIVE(*reloc_location(elf, sechdr, r)); + int offset; switch (r_typ) { case R_ARM_ABS32: r->r_addend = inst + sym->st_value; break; + case R_ARM_MOVW_ABS_NC: + case R_ARM_MOVT_ABS: + offset = ((inst & 0xf0000) >> 4) | (inst & 0xfff); + offset = (offset ^ 0x8000) - 0x8000; + offset += sym->st_value; + r->r_addend = offset; + break; case R_ARM_PC24: case R_ARM_CALL: case R_ARM_JUMP24: From patchwork Sun May 21 16:04:09 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masahiro Yamada X-Patchwork-Id: 13249435 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4B9F2C77B73 for ; Sun, 21 May 2023 16:05:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230176AbjEUQFZ (ORCPT ); Sun, 21 May 2023 12:05:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55148 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230166AbjEUQFX (ORCPT ); Sun, 21 May 2023 12:05:23 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 39D5DC7; Sun, 21 May 2023 09:05:22 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id C52B460FB0; Sun, 21 May 2023 16:05:21 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B1DC5C4339E; Sun, 21 May 2023 16:05:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1684685121; bh=PLUcGmlR+NY3691REVWSeKyvhjpYj54g/UwfJ/FUdKg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OAXOJlDLX6Ry1NQApjGojF27AzvcfLiHkd+tvuPCx1Lf7mEWKxFY0WHa6cGeNguC4 swIUrX/7WeBad0n8PfynPYA/Kk0YzmiEe4FwgeM6nYe/X/LUr2LsN5PUNGi2ROVtqy hvAmWrD2445kZJHyO55munZM7D+0JFHj1jkrRbvDVfb1eVW80XOLbEY4DKCE9CIX+R FpebEZfge4PFQqO42Q++f6VQ+thJJXINN62NtnDTwqrE2MCPBoEgsxFJREGPppEE4w T0ZkYbYZI/tM81EC5uJmeaYVmdlOwL/z17B1Ju7b7eh/E9UtbJj6V4fmv6i43EzZAq wcMXr5uM570LQ== From: Masahiro Yamada To: linux-kbuild@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Nathan Chancellor , Nick Desaulniers , Nicolas Schier , Masahiro Yamada Subject: [PATCH v6 04/20] modpost: remove unused argument from secref_whitelist() Date: Mon, 22 May 2023 01:04:09 +0900 Message-Id: <20230521160426.1881124-5-masahiroy@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230521160426.1881124-1-masahiroy@kernel.org> References: <20230521160426.1881124-1-masahiroy@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org secref_whitelist() does not use the argument 'mismatch'. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- scripts/mod/modpost.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index ed2301e951a9..d2329ac32177 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -1035,8 +1035,7 @@ static const struct sectioncheck *section_mismatch( * refsymname = *.constprop.* * **/ -static int secref_whitelist(const struct sectioncheck *mismatch, - const char *fromsec, const char *fromsym, +static int secref_whitelist(const char *fromsec, const char *fromsym, const char *tosec, const char *tosym) { /* Check for pattern 1 */ @@ -1206,7 +1205,7 @@ static void default_mismatch_handler(const char *modname, struct elf_info *elf, tosym = sym_name(elf, to); /* check whitelist - we may ignore it */ - if (!secref_whitelist(mismatch, fromsec, fromsym, tosec, tosym)) + if (!secref_whitelist(fromsec, fromsym, tosec, tosym)) return; sec_mismatch_count++; From patchwork Sun May 21 16:04:10 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masahiro Yamada X-Patchwork-Id: 13249438 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F3FCFC77B73 for ; Sun, 21 May 2023 16:05:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230163AbjEUQF1 (ORCPT ); Sun, 21 May 2023 12:05:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55186 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230179AbjEUQFZ (ORCPT ); Sun, 21 May 2023 12:05:25 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 31E12DB; Sun, 21 May 2023 09:05:24 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 9E53860ECB; Sun, 21 May 2023 16:05:23 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A4B1FC433EF; Sun, 21 May 2023 16:05:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1684685123; bh=8ebBj1H5+fQEZ8XTbWPo2Yu/XZ2oEgvvBLIxSqvFjiI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VtSxQ55xiiPeLMuns3WBbXD0ipzJ4c8DgUzXuGqJ5e2EZLMif+X/aydsuyrpKr09c Yvdl0Os3Sl9meD3RS5OCV9xIAf80M8/z2c5fiq3Xz7oeZHpyNIYiO+H05DOIojwnWQ C7o8AjrUlqfw8xzFl9P9ZtXC3rJa53r8j8a0i3rXFulX9wCDZ1ylgZTdLmQrCnTDkN dueDM0qd5oKmz8N/XqqsChCQ3yNWGjUHuThWE0e+YOZZFpj9gCZCj/YGlr6J1j+5fz lwug6aJ9QZ7RZp23X1LyegOqL/GNh2JWd3hhGbp/Ou3VoVbN1hW1uCtI74tqZSlZcE JCJEMQOqCaGrQ== From: Masahiro Yamada To: linux-kbuild@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Nathan Chancellor , Nick Desaulniers , Nicolas Schier , Masahiro Yamada Subject: [PATCH v6 05/20] modpost: refactor find_fromsym() and find_tosym() Date: Mon, 22 May 2023 01:04:10 +0900 Message-Id: <20230521160426.1881124-6-masahiroy@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230521160426.1881124-1-masahiroy@kernel.org> References: <20230521160426.1881124-1-masahiroy@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org find_fromsym() and find_tosym() are similar - both of them iterate in the .symtab section and return the nearest symbol. The difference between them is that find_tosym() allows a negative distance, but the distance must be less than 20. Factor out the common part into find_nearest_sym(). Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- Changes in v6: - Revive the check for distance less than 20 scripts/mod/modpost.c | 95 ++++++++++++++++--------------------------- 1 file changed, 36 insertions(+), 59 deletions(-) diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index d2329ac32177..6ac0d571542c 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -1104,81 +1104,58 @@ static inline int is_valid_name(struct elf_info *elf, Elf_Sym *sym) return !is_mapping_symbol(name); } -/** - * Find symbol based on relocation record info. - * In some cases the symbol supplied is a valid symbol so - * return refsym. If is_valid_name() == true, we assume this is a valid symbol. - * In other cases the symbol needs to be looked up in the symbol table - * based on section and address. - * **/ -static Elf_Sym *find_tosym(struct elf_info *elf, Elf64_Sword addr, - Elf_Sym *relsym) +/* Look up the nearest symbol based on the section and the address */ +static Elf_Sym *find_nearest_sym(struct elf_info *elf, Elf_Addr addr, + unsigned int secndx, bool allow_negative, + Elf_Addr min_distance) { Elf_Sym *sym; Elf_Sym *near = NULL; - Elf64_Sword distance = 20; - Elf64_Sword d; - unsigned int relsym_secindex; - - if (is_valid_name(elf, relsym)) - return relsym; - - /* - * Strive to find a better symbol name, but the resulting name does not - * always match the symbol referenced in the original code. - */ - relsym_secindex = get_secindex(elf, relsym); - for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) { - if (get_secindex(elf, sym) != relsym_secindex) - continue; - if (ELF_ST_TYPE(sym->st_info) == STT_SECTION) - continue; - if (!is_valid_name(elf, sym)) - continue; - if (sym->st_value == addr) - return sym; - /* Find a symbol nearby - addr are maybe negative */ - d = sym->st_value - addr; - if (d < 0) - d = addr - sym->st_value; - if (d < distance) { - distance = d; - near = sym; - } - } - /* We need a close match */ - if (distance < 20) - return near; - else - return NULL; -} - -/* - * Find symbols before or equal addr and after addr - in the section sec. - * If we find two symbols with equal offset prefer one with a valid name. - * The ELF format may have a better way to detect what type of symbol - * it is, but this works for now. - **/ -static Elf_Sym *find_fromsym(struct elf_info *elf, Elf_Addr addr, - unsigned int secndx) -{ - Elf_Sym *sym; - Elf_Sym *near = NULL; - Elf_Addr distance = ~0; + Elf_Addr distance; for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) { if (get_secindex(elf, sym) != secndx) continue; if (!is_valid_name(elf, sym)) continue; - if (sym->st_value <= addr && addr - sym->st_value <= distance) { + + if (addr >= sym->st_value) distance = addr - sym->st_value; + else if (allow_negative) + distance = sym->st_value - addr; + else + continue; + + if (distance <= min_distance) { + min_distance = distance; near = sym; } + + if (min_distance == 0) + break; } return near; } +static Elf_Sym *find_fromsym(struct elf_info *elf, Elf_Addr addr, + unsigned int secndx) +{ + return find_nearest_sym(elf, addr, secndx, false, ~0); +} + +static Elf_Sym *find_tosym(struct elf_info *elf, Elf_Addr addr, Elf_Sym *sym) +{ + /* If the supplied symbol has a valid name, return it */ + if (is_valid_name(elf, sym)) + return sym; + + /* + * Strive to find a better symbol name, but the resulting name does not + * always match the symbol referenced in the original code. + */ + return find_nearest_sym(elf, addr, get_secindex(elf, sym), true, 20); +} + static bool is_executable_section(struct elf_info *elf, unsigned int secndx) { if (secndx > elf->num_sections) From patchwork Sun May 21 16:04:11 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masahiro Yamada X-Patchwork-Id: 13249437 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1E379C7EE2A for ; Sun, 21 May 2023 16:05:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230180AbjEUQF3 (ORCPT ); Sun, 21 May 2023 12:05:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55208 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230108AbjEUQF1 (ORCPT ); Sun, 21 May 2023 12:05:27 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F3732D2; Sun, 21 May 2023 09:05:25 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 6924660ECB; Sun, 21 May 2023 16:05:25 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7EB41C4339E; Sun, 21 May 2023 16:05:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1684685124; bh=621Nlo8JQEog+0qRcxqr1Gngu/9Y6pP2Btj4yQo7BvM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ssgjpQhP0UJdm8/pwcjsks+/LxMRn5wXE4R/AeWLExIo/RZ6mTxYxtzspxWR2TnEW hmzOW4v+2SmLKxfa34EHvdfZ0HdweiUaUww2KQbKQb+oRe3WZWAomiFnck9agvZ3bg HvByDO9lHsdXxXvWr0KYThNIg7w3o2SsmCNH6McQyerajs37JwuYj/cXFhVoolloMv cxI9Gq9dB/HXlNIXpswMskOjPfDnx5/35oOtWxUw39mbsebFuGD4fRcXoRzZn5SajK QQOks0X30wswEE+yjn6GN4h7Up6m4VxAvLViID0ntOOyPcmbB3bgeMZzUEV1Bynuw+ 02oVvGI+SbPiA== From: Masahiro Yamada To: linux-kbuild@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Nathan Chancellor , Nick Desaulniers , Nicolas Schier , Masahiro Yamada Subject: [PATCH v6 06/20] modpost: unify 'sym' and 'to' in default_mismatch_handler() Date: Mon, 22 May 2023 01:04:11 +0900 Message-Id: <20230521160426.1881124-7-masahiroy@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230521160426.1881124-1-masahiroy@kernel.org> References: <20230521160426.1881124-1-masahiroy@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org find_tosym() takes 'sym' and stores the return value to another variable 'to'. You can use the same variable because we want to replace the original one when appropriate. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- scripts/mod/modpost.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 6ac0d571542c..7848bacd4b42 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -1166,11 +1166,10 @@ static bool is_executable_section(struct elf_info *elf, unsigned int secndx) static void default_mismatch_handler(const char *modname, struct elf_info *elf, const struct sectioncheck* const mismatch, - Elf_Rela *r, Elf_Sym *sym, + Elf_Rela *r, Elf_Sym *tsym, unsigned int fsecndx, const char *fromsec, const char *tosec) { - Elf_Sym *to; Elf_Sym *from; const char *tosym; const char *fromsym; @@ -1178,8 +1177,8 @@ static void default_mismatch_handler(const char *modname, struct elf_info *elf, from = find_fromsym(elf, r->r_offset, fsecndx); fromsym = sym_name(elf, from); - to = find_tosym(elf, r->r_addend, sym); - tosym = sym_name(elf, to); + tsym = find_tosym(elf, r->r_addend, tsym); + tosym = sym_name(elf, tsym); /* check whitelist - we may ignore it */ if (!secref_whitelist(fromsec, fromsym, tosec, tosym)) @@ -1214,7 +1213,7 @@ static void default_mismatch_handler(const char *modname, struct elf_info *elf, "You might get more information about where this is\n" "coming from by using scripts/check_extable.sh %s\n", fromsec, (long)r->r_offset, tosec, modname); - else if (is_executable_section(elf, get_secindex(elf, sym))) + else if (is_executable_section(elf, get_secindex(elf, tsym))) warn("The relocation at %s+0x%lx references\n" "section \"%s\" which is not in the list of\n" "authorized sections. If you're adding a new section\n" From patchwork Sun May 21 16:04:12 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masahiro Yamada X-Patchwork-Id: 13249439 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3F2FEC7EE2A for ; Sun, 21 May 2023 16:05:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230362AbjEUQFk (ORCPT ); Sun, 21 May 2023 12:05:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55206 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230199AbjEUQFa (ORCPT ); Sun, 21 May 2023 12:05:30 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4557CE4; Sun, 21 May 2023 09:05:28 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 8101960EBB; Sun, 21 May 2023 16:05:27 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5823EC433EF; Sun, 21 May 2023 16:05:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1684685126; bh=DllT3ZPOBUigMQGFIvZ6Cw5LDSBjW9pG7B4U9kbXEAs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CzdAmYmcSc6P4QtLbs6CZOmM4Ynr9rvb8H9OAAENgMqVmNjP4ZbwDFw9N+tZKFkx3 SNd4r/qGJ/nJJ5VgblK16Q+Ie4vevA7SKvgCX+wXtdfpuR8AfBsZGXILB5NprMxTKq WyN6xInHOqLDUc9uvpjyO4RncUy+ORFNitoH6Il+sJRr0UbwH9vwFR/eCT97cQqgMl m0rWlqApLCsf6K2kbovLLLkfGWidhoa7GIWtI3epVjqQmDp8h7qci6rd6ruXxZik0J EhqUYGOmYr6K/IhcgMrXdRJOqOKaRo6zv6zM6gr7YWeLUgRazDwzCkEj3uZg3QOenR 2lYYx6MMVfrfg== From: Masahiro Yamada To: linux-kbuild@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Nathan Chancellor , Nick Desaulniers , Nicolas Schier , Masahiro Yamada Subject: [PATCH v6 07/20] modpost: replace r->r_offset, r->r_addend with faddr, taddr Date: Mon, 22 May 2023 01:04:12 +0900 Message-Id: <20230521160426.1881124-8-masahiroy@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230521160426.1881124-1-masahiroy@kernel.org> References: <20230521160426.1881124-1-masahiroy@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org r_offset/r_addend holds the offset address from/to which a symbol is referenced. It is unclear unless you are familiar with ELF. Rename them to faddr, taddr, respectively. The prefix 'f' means 'from', 't' means 'to'. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- scripts/mod/modpost.c | 34 +++++++++++++++++++--------------- 1 file changed, 19 insertions(+), 15 deletions(-) diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 7848bacd4b42..f364738a236e 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -1166,18 +1166,18 @@ static bool is_executable_section(struct elf_info *elf, unsigned int secndx) static void default_mismatch_handler(const char *modname, struct elf_info *elf, const struct sectioncheck* const mismatch, - Elf_Rela *r, Elf_Sym *tsym, - unsigned int fsecndx, const char *fromsec, - const char *tosec) + Elf_Sym *tsym, + unsigned int fsecndx, const char *fromsec, Elf_Addr faddr, + const char *tosec, Elf_Addr taddr) { Elf_Sym *from; const char *tosym; const char *fromsym; - from = find_fromsym(elf, r->r_offset, fsecndx); + from = find_fromsym(elf, faddr, fsecndx); fromsym = sym_name(elf, from); - tsym = find_tosym(elf, r->r_addend, tsym); + tsym = find_tosym(elf, taddr, tsym); tosym = sym_name(elf, tsym); /* check whitelist - we may ignore it */ @@ -1204,7 +1204,7 @@ static void default_mismatch_handler(const char *modname, struct elf_info *elf, break; case EXTABLE_TO_NON_TEXT: warn("%s(%s+0x%lx): Section mismatch in reference to the %s:%s\n", - modname, fromsec, (long)r->r_offset, tosec, tosym); + modname, fromsec, (long)faddr, tosec, tosym); if (match(tosec, mismatch->bad_tosec)) fatal("The relocation at %s+0x%lx references\n" @@ -1212,7 +1212,7 @@ static void default_mismatch_handler(const char *modname, struct elf_info *elf, "Something is seriously wrong and should be fixed.\n" "You might get more information about where this is\n" "coming from by using scripts/check_extable.sh %s\n", - fromsec, (long)r->r_offset, tosec, modname); + fromsec, (long)faddr, tosec, modname); else if (is_executable_section(elf, get_secindex(elf, tsym))) warn("The relocation at %s+0x%lx references\n" "section \"%s\" which is not in the list of\n" @@ -1221,17 +1221,18 @@ static void default_mismatch_handler(const char *modname, struct elf_info *elf, "list of authorized sections to jump to on fault.\n" "This can be achieved by adding \"%s\" to\n" "OTHER_TEXT_SECTIONS in scripts/mod/modpost.c.\n", - fromsec, (long)r->r_offset, tosec, tosec, tosec); + fromsec, (long)faddr, tosec, tosec, tosec); else error("%s+0x%lx references non-executable section '%s'\n", - fromsec, (long)r->r_offset, tosec); + fromsec, (long)faddr, tosec); break; } } static void check_section_mismatch(const char *modname, struct elf_info *elf, - Elf_Rela *r, Elf_Sym *sym, - unsigned int fsecndx, const char *fromsec) + Elf_Sym *sym, + unsigned int fsecndx, const char *fromsec, + Elf_Addr faddr, Elf_Addr taddr) { const char *tosec = sec_name(elf, get_secindex(elf, sym)); const struct sectioncheck *mismatch = section_mismatch(fromsec, tosec); @@ -1239,8 +1240,9 @@ static void check_section_mismatch(const char *modname, struct elf_info *elf, if (!mismatch) return; - default_mismatch_handler(modname, elf, mismatch, r, sym, fsecndx, fromsec, - tosec); + default_mismatch_handler(modname, elf, mismatch, sym, + fsecndx, fromsec, faddr, + tosec, taddr); } static unsigned int *reloc_location(struct elf_info *elf, @@ -1406,7 +1408,8 @@ static void section_rela(const char *modname, struct elf_info *elf, /* Skip special sections */ if (is_shndx_special(sym->st_shndx)) continue; - check_section_mismatch(modname, elf, &r, sym, fsecndx, fromsec); + check_section_mismatch(modname, elf, sym, + fsecndx, fromsec, r.r_offset, r.r_addend); } } @@ -1464,7 +1467,8 @@ static void section_rel(const char *modname, struct elf_info *elf, /* Skip special sections */ if (is_shndx_special(sym->st_shndx)) continue; - check_section_mismatch(modname, elf, &r, sym, fsecndx, fromsec); + check_section_mismatch(modname, elf, sym, + fsecndx, fromsec, r.r_offset, r.r_addend); } } From patchwork Sun May 21 16:04:13 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masahiro Yamada X-Patchwork-Id: 13249440 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DD2F6C77B73 for ; Sun, 21 May 2023 16:05:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229626AbjEUQFm (ORCPT ); Sun, 21 May 2023 12:05:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55458 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230317AbjEUQFf (ORCPT ); Sun, 21 May 2023 12:05:35 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E1459118; Sun, 21 May 2023 09:05:29 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 6AE3D60F9D; Sun, 21 May 2023 16:05:29 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 63CCCC433A0; Sun, 21 May 2023 16:05:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1684685128; bh=zRzYFZ5lz7mHPL94B6DS35Xto1/srS4BQ/bsgLZFHtc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=dv23FCUuRpa+ZEAYxnbcBXiZtmulasqyIrSh8r9/2+5am8ohuf6zVRSwxHaxNCfYb LBB8YG3NeWJnXaHLCc6TejAnMgRV1sUtv8so12TbAgLtIzst4SBrW0CZISIl2lDmXY ZnFYRh1fkJHDOAVuFdk7Y88Fn2nCLjqCQuSjY5bBdx+SSe/JfjLO+DVYdSQzs1mc/l XXUyTIYKapKFM0kWcmeMyiOhxRjtaPKKJSLCTTKAuYPukwEndFB917bfiU27rbX+Fz zi6LuZbk/dq2n8zX/40hartEu++K5PNXlWATifFDKSOjC0pRTT+Afi0HlbEaa8FXxt MUuCLR3zeilDg== From: Masahiro Yamada To: linux-kbuild@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Nathan Chancellor , Nick Desaulniers , Nicolas Schier , Masahiro Yamada Subject: [PATCH v6 08/20] modpost: remove is_shndx_special() check from section_rel(a) Date: Mon, 22 May 2023 01:04:13 +0900 Message-Id: <20230521160426.1881124-9-masahiroy@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230521160426.1881124-1-masahiroy@kernel.org> References: <20230521160426.1881124-1-masahiroy@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org This check is unneeded. Without it, sec_name() will returns the null string "", then section_mismatch() will return immediately. Anyway, special section indices rarely appear in these loops. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- Changes in v6: - Remove is_shndx_special() definition scripts/mod/modpost.c | 16 ++++------------ scripts/mod/modpost.h | 5 ----- 2 files changed, 4 insertions(+), 17 deletions(-) diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index f364738a236e..40fac4f64fcd 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -1361,7 +1361,6 @@ static int addend_mips_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r) static void section_rela(const char *modname, struct elf_info *elf, Elf_Shdr *sechdr) { - Elf_Sym *sym; Elf_Rela *rela; Elf_Rela r; unsigned int r_sym; @@ -1404,11 +1403,8 @@ static void section_rela(const char *modname, struct elf_info *elf, continue; break; } - sym = elf->symtab_start + r_sym; - /* Skip special sections */ - if (is_shndx_special(sym->st_shndx)) - continue; - check_section_mismatch(modname, elf, sym, + + check_section_mismatch(modname, elf, elf->symtab_start + r_sym, fsecndx, fromsec, r.r_offset, r.r_addend); } } @@ -1416,7 +1412,6 @@ static void section_rela(const char *modname, struct elf_info *elf, static void section_rel(const char *modname, struct elf_info *elf, Elf_Shdr *sechdr) { - Elf_Sym *sym; Elf_Rel *rel; Elf_Rela r; unsigned int r_sym; @@ -1463,11 +1458,8 @@ static void section_rel(const char *modname, struct elf_info *elf, default: fatal("Please add code to calculate addend for this architecture\n"); } - sym = elf->symtab_start + r_sym; - /* Skip special sections */ - if (is_shndx_special(sym->st_shndx)) - continue; - check_section_mismatch(modname, elf, sym, + + check_section_mismatch(modname, elf, elf->symtab_start + r_sym, fsecndx, fromsec, r.r_offset, r.r_addend); } } diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h index 1178f40a73f3..b1e2d95f8047 100644 --- a/scripts/mod/modpost.h +++ b/scripts/mod/modpost.h @@ -151,11 +151,6 @@ struct elf_info { Elf32_Word *symtab_shndx_stop; }; -static inline int is_shndx_special(unsigned int i) -{ - return i != SHN_XINDEX && i >= SHN_LORESERVE && i <= SHN_HIRESERVE; -} - /* Accessor for sym->st_shndx, hides ugliness of "64k sections" */ static inline unsigned int get_secindex(const struct elf_info *info, const Elf_Sym *sym) From patchwork Sun May 21 16:04:14 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masahiro Yamada X-Patchwork-Id: 13249441 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D1EB9C77B7C for ; Sun, 21 May 2023 16:06:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230448AbjEUQGB (ORCPT ); Sun, 21 May 2023 12:06:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55248 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230393AbjEUQFl (ORCPT ); Sun, 21 May 2023 12:05:41 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4E126186; Sun, 21 May 2023 09:05:32 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 554BB60ECB; Sun, 21 May 2023 16:05:31 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 56A81C433D2; Sun, 21 May 2023 16:05:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1684685130; bh=NjatIeEtMiORYtM/vXhp4DguRc7ec1+8yCNOZt2lIiE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bFERoLOh/Bild/3FCF3CRdl+SWSOHvBQR2ytVF8Ylu7KJlSaJ+nMDdrc8mqEGfi3Q HeJ95pibtOGPZ3iVWJwqAmwuDaKNp6A/iegqyX8t3HAs5LnyaYYh8uL2d1VRX8TcJ0 XC2uceW6/4gNAX/hTUAd9gyPCUdW5AJh8MvilTpmY8TTiNuO0opoeQIy1qZggMZStW WYGa+YQrsINfPGuazzEbyLKa5g492mv8hh28OAnh4wj8iD2NlnFOH2KID0d8aDucRz jLndS72n79XHUmlCKVcmO5qhavnWan/UMcmFGjPpBowZ0n80sllJeUBRfEzKqBrE3F +kgOa/aMaNbjA== From: Masahiro Yamada To: linux-kbuild@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Nathan Chancellor , Nick Desaulniers , Nicolas Schier , Masahiro Yamada Subject: [PATCH v6 09/20] modpost: pass struct module pointer to check_section_mismatch() Date: Mon, 22 May 2023 01:04:14 +0900 Message-Id: <20230521160426.1881124-10-masahiroy@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230521160426.1881124-1-masahiroy@kernel.org> References: <20230521160426.1881124-1-masahiroy@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org The next commit will use it. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- scripts/mod/modpost.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 40fac4f64fcd..378fb9649545 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -1229,7 +1229,7 @@ static void default_mismatch_handler(const char *modname, struct elf_info *elf, } } -static void check_section_mismatch(const char *modname, struct elf_info *elf, +static void check_section_mismatch(struct module *mod, struct elf_info *elf, Elf_Sym *sym, unsigned int fsecndx, const char *fromsec, Elf_Addr faddr, Elf_Addr taddr) @@ -1240,7 +1240,7 @@ static void check_section_mismatch(const char *modname, struct elf_info *elf, if (!mismatch) return; - default_mismatch_handler(modname, elf, mismatch, sym, + default_mismatch_handler(mod->name, elf, mismatch, sym, fsecndx, fromsec, faddr, tosec, taddr); } @@ -1358,7 +1358,7 @@ static int addend_mips_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r) #define R_LARCH_SUB32 55 #endif -static void section_rela(const char *modname, struct elf_info *elf, +static void section_rela(struct module *mod, struct elf_info *elf, Elf_Shdr *sechdr) { Elf_Rela *rela; @@ -1404,12 +1404,12 @@ static void section_rela(const char *modname, struct elf_info *elf, break; } - check_section_mismatch(modname, elf, elf->symtab_start + r_sym, + check_section_mismatch(mod, elf, elf->symtab_start + r_sym, fsecndx, fromsec, r.r_offset, r.r_addend); } } -static void section_rel(const char *modname, struct elf_info *elf, +static void section_rel(struct module *mod, struct elf_info *elf, Elf_Shdr *sechdr) { Elf_Rel *rel; @@ -1459,7 +1459,7 @@ static void section_rel(const char *modname, struct elf_info *elf, fatal("Please add code to calculate addend for this architecture\n"); } - check_section_mismatch(modname, elf, elf->symtab_start + r_sym, + check_section_mismatch(mod, elf, elf->symtab_start + r_sym, fsecndx, fromsec, r.r_offset, r.r_addend); } } @@ -1476,19 +1476,19 @@ static void section_rel(const char *modname, struct elf_info *elf, * to find all references to a section that reference a section that will * be discarded and warns about it. **/ -static void check_sec_ref(const char *modname, struct elf_info *elf) +static void check_sec_ref(struct module *mod, struct elf_info *elf) { int i; Elf_Shdr *sechdrs = elf->sechdrs; /* Walk through all sections */ for (i = 0; i < elf->num_sections; i++) { - check_section(modname, elf, &elf->sechdrs[i]); + check_section(mod->name, elf, &elf->sechdrs[i]); /* We want to process only relocation sections and not .init */ if (sechdrs[i].sh_type == SHT_RELA) - section_rela(modname, elf, &elf->sechdrs[i]); + section_rela(mod, elf, &elf->sechdrs[i]); else if (sechdrs[i].sh_type == SHT_REL) - section_rel(modname, elf, &elf->sechdrs[i]); + section_rel(mod, elf, &elf->sechdrs[i]); } } @@ -1659,7 +1659,7 @@ static void read_symbols(const char *modname) sym_get_data(&info, sym)); } - check_sec_ref(modname, &info); + check_sec_ref(mod, &info); if (!mod->is_vmlinux) { version = get_modinfo(&info, "version"); From patchwork Sun May 21 16:04:15 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masahiro Yamada X-Patchwork-Id: 13249442 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 08B27C77B7C for ; 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s=k20201202; t=1684685132; bh=09b5kPtFfLZTJTzF2I+byBFVfggNQkTgMDTDl5sdsoo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=H0ILufWJl4SKM2LhVv9iUVqPU5AwboL2YBbCDoHXkeLmBeixZ+j74GDcuXt+CwSui psqNo+VA4SEIOSbUC7Snlo91j4DBe0JtZ3KmPtvDGnC1NK8KFY6jKBmfvWbEOJm/jz /UYb2J7VGkldGsDIoUmd2W88d+5ELWeyWDvgbmGnCIw5dhdpBe36IMr3LQRHbLbbY3 pSVepj8XwUb315+EMvkDc2I81BN6OOrBKHOjg2ioTX3TruiNVT2eucSDhUIjFd7i/0 62dzmSx+dZviarJkIR2QXciKVWX496SQGVNSAipky2lTfCpZy0YSYNAsevszurV/S3 u1AVCDN8keRRg== From: Masahiro Yamada To: linux-kbuild@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Nathan Chancellor , Nick Desaulniers , Nicolas Schier , Masahiro Yamada Subject: [PATCH v6 10/20] kbuild: generate KSYMTAB entries by modpost Date: Mon, 22 May 2023 01:04:15 +0900 Message-Id: <20230521160426.1881124-11-masahiroy@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230521160426.1881124-1-masahiroy@kernel.org> References: <20230521160426.1881124-1-masahiroy@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org Commit 7b4537199a4a ("kbuild: link symbol CRCs at final link, removing CONFIG_MODULE_REL_CRCS") made modpost output CRCs in the same way whether the EXPORT_SYMBOL() is placed in *.c or *.S. This commit applies a similar approach to the entire data structure of EXPORT_SYMBOL() for further cleanups. The EXPORT_SYMBOL() compilation is split into two stages. When a source file is compiled, EXPORT_SYMBOL() is converted into a dummy symbol in the .export_symbol section. For example, EXPORT_SYMBOL(foo); EXPORT_SYMBOL_NS_GPL(bar, BAR_NAMESPACE); will be encoded into the following assembly code: .section ".export_symbol","a" __export_symbol__foo: .asciz "" .balign 8 .quad foo .previous .section ".export_symbol","a" __export_symbol_gpl_bar: .asciz "BAR_NAMESPACE" .balign 8 .quad bar .previous They are just markers to tell modpost the name, license, and namespace of the symbols. They will be dropped from the final vmlinux and modules because the *(.export_symbol) will go into /DISCARD/ in the linker script. Then, modpost extracts all the information about EXPORT_SYMBOL() from the .export_symbol section, and generates C code: KSYMTAB_FUNC(foo, "", ""); KSYMTAB_FUNC(bar, "_gpl", "BAR_NAMESPACE"); KSYMTAB_FUNC() (or KSYMTAB_DATA() if it is data) is expanded to struct kernel_symbol that will be linked to the vmlinux or a module. With this change, EXPORT_SYMBOL() works in the same way for *.c and *.S files, providing the following benefits. [1] Deprecate EXPORT_DATA_SYMBOL() In the old days, EXPORT_SYMBOL() was only available in C files. To export a symbol in *.S, EXPORT_SYMBOL() was placed in a separate *.c file. arch/arm/kernel/armksyms.c is one example written in the classic manner. Commit 22823ab419d8 ("EXPORT_SYMBOL() for asm") removed this limitation. Since then, EXPORT_SYMBOL() can be placed close to the symbol definition in *.S files. It was a nice improvement. However, as that commit mentioned, you need to use EXPORT_DATA_SYMBOL() for data objects on some architectures. In the new approach, modpost checks symbol's type (STT_FUNC or not), and outputs KSYMTAB_FUNC() or KSYMTAB_DATA() accordingly. There are only two users of EXPORT_DATA_SYMBOL: EXPORT_DATA_SYMBOL_GPL(empty_zero_page) (arch/ia64/kernel/head.S) EXPORT_DATA_SYMBOL(ia64_ivt) (arch/ia64/kernel/ivt.S) They are transformed as follows and output into .vmlinux.export.c KSYMTAB_DATA(empty_zero_page, "_gpl", ""); KSYMTAB_DATA(ia64_ivt, "", ""); The other EXPORT_SYMBOL users in ia64 assembly are output as KSYMTAB_FUNC(). EXPORT_DATA_SYMBOL() is now deprecated. [2] merge and There are two similar header implementations: include/linux/export.h for .c files include/asm-generic/export.h for .S files Ideally, the functionality should be consistent between them, but they tend to diverge. Commit 8651ec01daed ("module: add support for symbol namespaces.") did not support the namespace for *.S files. This commit shifts the essential implementation part to C, which supports EXPORT_SYMBOL_NS() for *.S files. and will remain as a wrapper of for a while. They will be removed after #include directives are all replaced with #include . [3] Implement CONFIG_TRIM_UNUSED_KSYMS in one-pass algorithm (by a later commit) When CONFIG_TRIM_UNUSED_KSYMS is enabled, Kbuild recursively traverses the directory tree to determine which EXPORT_SYMBOL to trim. If an EXPORT_SYMBOL turns out to be unused by anyone, Kbuild begins the second traverse, where some source files are recompiled with their EXPORT_SYMBOL() tuned into a no-op. We can do this better now; modpost can selectively emit KSYMTAB entries that are really used by modules. Signed-off-by: Masahiro Yamada --- Changes in v6: - Fix build error on UML Changes in v5: - Fix build error on ARM Changes in v4: - Version 3 did not work if a same name symbol exists in a different compilation unit Fix it. Changes in v3: - Move struct kernel_symbol to kernel/module/internal.h Changes in v2: - Use KSYMTAB_FUNC and KSYMTAB_DATA for functions and data, respectively This distinction is needed for ia64. arch/ia64/include/asm/Kbuild | 1 + arch/ia64/include/asm/export.h | 3 - arch/um/os-Linux/user_syms.c | 9 ++- include/asm-generic/export.h | 84 ++----------------------- include/asm-generic/vmlinux.lds.h | 1 + include/linux/export-internal.h | 49 +++++++++++++++ include/linux/export.h | 98 +++++++++++------------------ include/linux/pm.h | 8 +-- kernel/module/internal.h | 12 ++++ scripts/Makefile.build | 8 +-- scripts/check-local-export | 4 +- scripts/mod/modpost.c | 100 ++++++++++++++++++++---------- scripts/mod/modpost.h | 1 + 13 files changed, 188 insertions(+), 190 deletions(-) delete mode 100644 arch/ia64/include/asm/export.h diff --git a/arch/ia64/include/asm/Kbuild b/arch/ia64/include/asm/Kbuild index aefae2efde9f..33733245f42b 100644 --- a/arch/ia64/include/asm/Kbuild +++ b/arch/ia64/include/asm/Kbuild @@ -1,6 +1,7 @@ # SPDX-License-Identifier: GPL-2.0 generated-y += syscall_table.h generic-y += agp.h +generic-y += export.h generic-y += kvm_para.h generic-y += mcs_spinlock.h generic-y += vtime.h diff --git a/arch/ia64/include/asm/export.h b/arch/ia64/include/asm/export.h deleted file mode 100644 index ad18c6583252..000000000000 --- a/arch/ia64/include/asm/export.h +++ /dev/null @@ -1,3 +0,0 @@ -/* EXPORT_DATA_SYMBOL != EXPORT_SYMBOL here */ -#define KSYM_FUNC(name) @fptr(name) -#include diff --git a/arch/um/os-Linux/user_syms.c b/arch/um/os-Linux/user_syms.c index 9b62a9d352b3..0b3a82aedbfa 100644 --- a/arch/um/os-Linux/user_syms.c +++ b/arch/um/os-Linux/user_syms.c @@ -38,10 +38,15 @@ EXPORT_SYMBOL(vsyscall_end); #endif /* Export symbols used by GCC for the stack protector. */ -extern void __stack_smash_handler(void *) __attribute__((weak)); +/* + * REVISIT: + * ARCH=um cannot enable CONFIG_STACKPROTECTOR because + * 'select HAVE_STACKPROTECTOR' is missing. Is this already broken? + */ +void (*__stack_smash_handler)(void *) __attribute__((weak)); EXPORT_SYMBOL(__stack_smash_handler); -extern long __guard __attribute__((weak)); +long __guard __attribute__((weak)); EXPORT_SYMBOL(__guard); #ifdef _FORTIFY_SOURCE diff --git a/include/asm-generic/export.h b/include/asm-generic/export.h index 5e4b1f2369d2..0ae9f38a904c 100644 --- a/include/asm-generic/export.h +++ b/include/asm-generic/export.h @@ -3,86 +3,12 @@ #define __ASM_GENERIC_EXPORT_H /* - * This comment block is used by fixdep. Please do not remove. - * - * When CONFIG_MODVERSIONS is changed from n to y, all source files having - * EXPORT_SYMBOL variants must be re-compiled because genksyms is run as a - * side effect of the *.o build rule. + * and are deprecated. + * Please include directly. */ +#include -#ifndef KSYM_FUNC -#define KSYM_FUNC(x) x -#endif -#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS -#define KSYM_ALIGN 4 -#elif defined(CONFIG_64BIT) -#define KSYM_ALIGN 8 -#else -#define KSYM_ALIGN 4 -#endif - -.macro __put, val, name -#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS - .long \val - ., \name - ., 0 -#elif defined(CONFIG_64BIT) - .quad \val, \name, 0 -#else - .long \val, \name, 0 -#endif -.endm - -/* - * note on .section use: we specify progbits since usage of the "M" (SHF_MERGE) - * section flag requires it. Use '%progbits' instead of '@progbits' since the - * former apparently works on all arches according to the binutils source. - */ - -.macro ___EXPORT_SYMBOL name,val,sec -#if defined(CONFIG_MODULES) && !defined(__DISABLE_EXPORTS) - .section ___ksymtab\sec+\name,"a" - .balign KSYM_ALIGN -__ksymtab_\name: - __put \val, __kstrtab_\name - .previous - .section __ksymtab_strings,"aMS",%progbits,1 -__kstrtab_\name: - .asciz "\name" - .previous -#endif -.endm - -#if defined(CONFIG_TRIM_UNUSED_KSYMS) - -#include -#include - -.macro __ksym_marker sym - .section ".discard.ksym","a" -__ksym_marker_\sym: - .previous -.endm - -#define __EXPORT_SYMBOL(sym, val, sec) \ - __ksym_marker sym; \ - __cond_export_sym(sym, val, sec, __is_defined(__KSYM_##sym)) -#define __cond_export_sym(sym, val, sec, conf) \ - ___cond_export_sym(sym, val, sec, conf) -#define ___cond_export_sym(sym, val, sec, enabled) \ - __cond_export_sym_##enabled(sym, val, sec) -#define __cond_export_sym_1(sym, val, sec) ___EXPORT_SYMBOL sym, val, sec -#define __cond_export_sym_0(sym, val, sec) /* nothing */ - -#else -#define __EXPORT_SYMBOL(sym, val, sec) ___EXPORT_SYMBOL sym, val, sec -#endif - -#define EXPORT_SYMBOL(name) \ - __EXPORT_SYMBOL(name, KSYM_FUNC(name),) -#define EXPORT_SYMBOL_GPL(name) \ - __EXPORT_SYMBOL(name, KSYM_FUNC(name), _gpl) -#define EXPORT_DATA_SYMBOL(name) \ - __EXPORT_SYMBOL(name, name,) -#define EXPORT_DATA_SYMBOL_GPL(name) \ - __EXPORT_SYMBOL(name, name,_gpl) +#define EXPORT_DATA_SYMBOL(name) EXPORT_SYMBOL(name) +#define EXPORT_DATA_SYMBOL_GPL(name) EXPORT_SYMBOL_GPL(name) #endif diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index d1f57e4868ed..e65d55e8819c 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -1006,6 +1006,7 @@ PATCHABLE_DISCARDS \ *(.discard) \ *(.discard.*) \ + *(.export_symbol) \ *(.modinfo) \ /* ld.bfd warns about .gnu.version* even when not emitted */ \ *(.gnu.version*) \ diff --git a/include/linux/export-internal.h b/include/linux/export-internal.h index fe7e6ba918f1..1c849db953a5 100644 --- a/include/linux/export-internal.h +++ b/include/linux/export-internal.h @@ -10,6 +10,55 @@ #include #include +#if defined(CONFIG_HAVE_ARCH_PREL32_RELOCATIONS) +/* + * relative reference: this reduces the size by half on 64-bit architectures, + * and eliminates the need for absolute relocations that require runtime + * processing on relocatable kernels. + */ +#define __KSYM_REF(sym) ".long " #sym "- ." +#elif defined(CONFIG_64BIT) +#define __KSYM_REF(sym) ".quad " #sym +#else +#define __KSYM_REF(sym) ".long " #sym +#endif + +/* + * For every exported symbol, do the following: + * + * - Put the name of the symbol and namespace (empty string "" for none) in + * __ksymtab_strings. + * - Place a struct kernel_symbol entry in the __ksymtab section. + * + * Note on .section use: we specify progbits since usage of the "M" (SHF_MERGE) + * section flag requires it. Use '%progbits' instead of '@progbits' since the + * former apparently works on all arches according to the binutils source. + */ +#define __KSYMTAB(name, sym, sec, ns) \ + asm(" .section \"__ksymtab_strings\",\"aMS\",%progbits,1" "\n" \ + "__kstrtab_" #name ":" "\n" \ + " .asciz \"" #name "\"" "\n" \ + "__kstrtabns_" #name ":" "\n" \ + " .asciz \"" ns "\"" "\n" \ + " .previous" "\n" \ + " .section \"___ksymtab" sec "+" #name "\", \"a\"" "\n" \ + " .balign 4" "\n" \ + "__ksymtab_" #name ":" "\n" \ + __KSYM_REF(sym) "\n" \ + __KSYM_REF(__kstrtab_ ##name) "\n" \ + __KSYM_REF(__kstrtabns_ ##name) "\n" \ + " .previous" "\n" \ + ) + +#ifdef CONFIG_IA64 +#define KSYM_FUNC(name) @fptr(name) +#else +#define KSYM_FUNC(name) name +#endif + +#define KSYMTAB_FUNC(name, sec, ns) __KSYMTAB(name, KSYM_FUNC(name), sec, ns) +#define KSYMTAB_DATA(name, sec, ns) __KSYMTAB(name, name, sec, ns) + #define SYMBOL_CRC(sym, crc, sec) \ asm(".section \"___kcrctab" sec "+" #sym "\",\"a\"" "\n" \ "__crc_" #sym ":" "\n" \ diff --git a/include/linux/export.h b/include/linux/export.h index 3f31ced0d977..32461a01608c 100644 --- a/include/linux/export.h +++ b/include/linux/export.h @@ -2,6 +2,7 @@ #ifndef _LINUX_EXPORT_H #define _LINUX_EXPORT_H +#include #include /* @@ -28,72 +29,35 @@ extern struct module __this_module; #else #define THIS_MODULE ((struct module *)0) #endif +#endif /* __ASSEMBLY__ */ -#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS -#include -/* - * Emit the ksymtab entry as a pair of relative references: this reduces - * the size by half on 64-bit architectures, and eliminates the need for - * absolute relocations that require runtime processing on relocatable - * kernels. - */ -#define __KSYMTAB_ENTRY(sym, sec) \ - __ADDRESSABLE(sym) \ - asm(" .section \"___ksymtab" sec "+" #sym "\", \"a\" \n" \ - " .balign 4 \n" \ - "__ksymtab_" #sym ": \n" \ - " .long " #sym "- . \n" \ - " .long __kstrtab_" #sym "- . \n" \ - " .long __kstrtabns_" #sym "- . \n" \ - " .previous \n") - -struct kernel_symbol { - int value_offset; - int name_offset; - int namespace_offset; -}; +#ifdef CONFIG_64BIT +#define __EXPORT_SYMBOL_REF(sym) .balign 8; .quad sym #else -#define __KSYMTAB_ENTRY(sym, sec) \ - static const struct kernel_symbol __ksymtab_##sym \ - __attribute__((section("___ksymtab" sec "+" #sym), used)) \ - __aligned(sizeof(void *)) \ - = { (unsigned long)&sym, __kstrtab_##sym, __kstrtabns_##sym } - -struct kernel_symbol { - unsigned long value; - const char *name; - const char *namespace; -}; +#define __EXPORT_SYMBOL_REF(sym) .balign 4; .long sym #endif +#define ____EXPORT_SYMBOL(sym, license, ns) \ + .section ".export_symbol","a" ; \ + __export_symbol_##license##_##sym: ; \ + .asciz ns ; \ + __EXPORT_SYMBOL_REF(sym) ; \ + .previous + #ifdef __GENKSYMS__ #define ___EXPORT_SYMBOL(sym, sec, ns) __GENKSYMS_EXPORT_SYMBOL(sym) +#elif defined(__ASSEMBLY__) + +#define ___EXPORT_SYMBOL(sym, license, ns) \ + ____EXPORT_SYMBOL(sym, license, ns) + #else -/* - * For every exported symbol, do the following: - * - * - Put the name of the symbol and namespace (empty string "" for none) in - * __ksymtab_strings. - * - Place a struct kernel_symbol entry in the __ksymtab section. - * - * note on .section use: we specify progbits since usage of the "M" (SHF_MERGE) - * section flag requires it. Use '%progbits' instead of '@progbits' since the - * former apparently works on all arches according to the binutils source. - */ -#define ___EXPORT_SYMBOL(sym, sec, ns) \ - extern typeof(sym) sym; \ - extern const char __kstrtab_##sym[]; \ - extern const char __kstrtabns_##sym[]; \ - asm(" .section \"__ksymtab_strings\",\"aMS\",%progbits,1 \n" \ - "__kstrtab_" #sym ": \n" \ - " .asciz \"" #sym "\" \n" \ - "__kstrtabns_" #sym ": \n" \ - " .asciz \"" ns "\" \n" \ - " .previous \n"); \ - __KSYMTAB_ENTRY(sym, sec) +#define ___EXPORT_SYMBOL(sym, license, ns) \ + __ADDRESSABLE(sym) \ + asm(__stringify(____EXPORT_SYMBOL(sym, license, ns))) #endif @@ -117,9 +81,21 @@ struct kernel_symbol { * from the $(NM) output (see scripts/gen_ksymdeps.sh). These symbols are * discarded in the final link stage. */ + +#ifdef __ASSEMBLY__ + +#define __ksym_marker(sym) \ + .section ".discard.ksym","a" ; \ +__ksym_marker_##sym: ; \ + .previous + +#else + #define __ksym_marker(sym) \ static int __ksym_marker_##sym[0] __section(".discard.ksym") __used +#endif + #define __EXPORT_SYMBOL(sym, sec, ns) \ __ksym_marker(sym); \ __cond_export_sym(sym, sec, ns, __is_defined(__KSYM_##sym)) @@ -147,11 +123,9 @@ struct kernel_symbol { #define _EXPORT_SYMBOL(sym, sec) __EXPORT_SYMBOL(sym, sec, "") #endif -#define EXPORT_SYMBOL(sym) _EXPORT_SYMBOL(sym, "") -#define EXPORT_SYMBOL_GPL(sym) _EXPORT_SYMBOL(sym, "_gpl") -#define EXPORT_SYMBOL_NS(sym, ns) __EXPORT_SYMBOL(sym, "", __stringify(ns)) -#define EXPORT_SYMBOL_NS_GPL(sym, ns) __EXPORT_SYMBOL(sym, "_gpl", __stringify(ns)) - -#endif /* !__ASSEMBLY__ */ +#define EXPORT_SYMBOL(sym) _EXPORT_SYMBOL(sym,) +#define EXPORT_SYMBOL_GPL(sym) _EXPORT_SYMBOL(sym,gpl) +#define EXPORT_SYMBOL_NS(sym, ns) __EXPORT_SYMBOL(sym,, __stringify(ns)) +#define EXPORT_SYMBOL_NS_GPL(sym, ns) __EXPORT_SYMBOL(sym,gpl, __stringify(ns)) #endif /* _LINUX_EXPORT_H */ diff --git a/include/linux/pm.h b/include/linux/pm.h index 035d9649eba4..aabb6bd8f89e 100644 --- a/include/linux/pm.h +++ b/include/linux/pm.h @@ -388,10 +388,10 @@ const struct dev_pm_ops name = { \ #define EXPORT_PM_FN_NS_GPL(name, ns) #endif -#define EXPORT_DEV_PM_OPS(name) _EXPORT_DEV_PM_OPS(name, "", "") -#define EXPORT_GPL_DEV_PM_OPS(name) _EXPORT_DEV_PM_OPS(name, "_gpl", "") -#define EXPORT_NS_DEV_PM_OPS(name, ns) _EXPORT_DEV_PM_OPS(name, "", #ns) -#define EXPORT_NS_GPL_DEV_PM_OPS(name, ns) _EXPORT_DEV_PM_OPS(name, "_gpl", #ns) +#define EXPORT_DEV_PM_OPS(name) _EXPORT_DEV_PM_OPS(name,, "") +#define EXPORT_GPL_DEV_PM_OPS(name) _EXPORT_DEV_PM_OPS(name,gpl, "") +#define EXPORT_NS_DEV_PM_OPS(name, ns) _EXPORT_DEV_PM_OPS(name,, #ns) +#define EXPORT_NS_GPL_DEV_PM_OPS(name, ns) _EXPORT_DEV_PM_OPS(name,gpl, #ns) /* * Use this if you want to use the same suspend and resume callbacks for suspend diff --git a/kernel/module/internal.h b/kernel/module/internal.h index dc7b0160c480..c8b7b4dcf782 100644 --- a/kernel/module/internal.h +++ b/kernel/module/internal.h @@ -32,6 +32,18 @@ /* Maximum number of characters written by module_flags() */ #define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4) +struct kernel_symbol { +#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS + int value_offset; + int name_offset; + int namespace_offset; +#else + unsigned long value; + const char *name; + const char *namespace; +#endif +}; + extern struct mutex module_mutex; extern struct list_head modules; diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 9f94fc83f086..6bf026a304e4 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -161,7 +161,7 @@ quiet_cmd_cc_o_c = CC $(quiet_modtag) $@ ifdef CONFIG_MODVERSIONS # When module versioning is enabled the following steps are executed: # o compile a .o from .c -# o if .o doesn't contain a __ksymtab version, i.e. does +# o if .o doesn't contain a __export_symbol*, i.e. does # not export symbols, it's done. # o otherwise, we calculate symbol versions using the good old # genksyms on the preprocessed source and dump them into the .cmd file. @@ -169,7 +169,7 @@ ifdef CONFIG_MODVERSIONS # be compiled and linked to the kernel and/or modules. gen_symversions = \ - if $(NM) $@ 2>/dev/null | grep -q __ksymtab; then \ + if $(NM) $@ 2>/dev/null | grep -q '__export_symbol_[^_]*_'; then \ $(call cmd_gensymtypes_$(1),$(KBUILD_SYMTYPES),$(@:.o=.symtypes)) \ >> $(dot-target).cmd; \ fi @@ -340,9 +340,7 @@ $(obj)/%.ll: $(src)/%.rs FORCE cmd_gensymtypes_S = \ { echo "\#include " ; \ echo "\#include " ; \ - $(CPP) $(a_flags) $< | \ - grep "\<___EXPORT_SYMBOL\>" | \ - sed 's/.*___EXPORT_SYMBOL[[:space:]]*\([a-zA-Z0-9_]*\)[[:space:]]*,.*/EXPORT_SYMBOL(\1);/' ; } | \ + $(NM) $@ | sed -n 's/.*__export_symbol_[^_]*_\(.*\)/EXPORT_SYMBOL(\1);/p' ; } | \ $(CPP) -D__GENKSYMS__ $(c_flags) -xc - | $(genksyms) quiet_cmd_cc_symtypes_S = SYM $(quiet_modtag) $@ diff --git a/scripts/check-local-export b/scripts/check-local-export index f90b5a9c67b3..969a313b9299 100755 --- a/scripts/check-local-export +++ b/scripts/check-local-export @@ -46,9 +46,9 @@ BEGIN { { symbol_types[$3]=$2 } # append the exported symbol to the array -($3 ~ /^__ksymtab_/) { +($3 ~ /^__export_symbol_(gpl)?_.*/) { export_symbols[i] = $3 - sub(/^__ksymtab_/, "", export_symbols[i]) + sub(/^__export_symbol_(gpl)?_/, "", export_symbols[i]) i++ } diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 378fb9649545..8b94090d0743 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -215,6 +215,7 @@ struct symbol { unsigned int crc; bool crc_valid; bool weak; + bool is_func; bool is_gpl_only; /* exported by EXPORT_SYMBOL_GPL */ char name[]; }; @@ -531,6 +532,8 @@ static int parse_elf(struct elf_info *info, const char *filename) fatal("%s has NOBITS .modinfo\n", filename); info->modinfo = (void *)hdr + sechdrs[i].sh_offset; info->modinfo_len = sechdrs[i].sh_size; + } else if (!strcmp(secname, ".export_symbol")) { + info->export_symbol_secndx = i; } if (sechdrs[i].sh_type == SHT_SYMTAB) { @@ -653,18 +656,6 @@ static void handle_symbol(struct module *mod, struct elf_info *info, ELF_ST_BIND(sym->st_info) == STB_WEAK); break; default: - /* All exported symbols */ - if (strstarts(symname, "__ksymtab_")) { - const char *name, *secname; - - name = symname + strlen("__ksymtab_"); - secname = sec_name(info, get_secindex(info, sym)); - - if (strstarts(secname, "___ksymtab_gpl+")) - sym_add_exported(name, mod, true); - else if (strstarts(secname, "___ksymtab+")) - sym_add_exported(name, mod, false); - } if (strcmp(symname, "init_module") == 0) mod->has_init = true; if (strcmp(symname, "cleanup_module") == 0) @@ -865,7 +856,6 @@ enum mismatch { XXXEXIT_TO_SOME_EXIT, ANY_INIT_TO_ANY_EXIT, ANY_EXIT_TO_ANY_INIT, - EXPORT_TO_INIT_EXIT, EXTABLE_TO_NON_TEXT, }; @@ -947,12 +937,6 @@ static const struct sectioncheck sectioncheck[] = { .bad_tosec = { INIT_SECTIONS, NULL }, .mismatch = ANY_INIT_TO_ANY_EXIT, }, -/* Do not export init/exit functions or data */ -{ - .fromsec = { "___ksymtab*", NULL }, - .bad_tosec = { INIT_SECTIONS, EXIT_SECTIONS, NULL }, - .mismatch = EXPORT_TO_INIT_EXIT, -}, { .fromsec = { "__ex_table", NULL }, /* If you're adding any new black-listed sections in here, consider @@ -1198,10 +1182,6 @@ static void default_mismatch_handler(const char *modname, struct elf_info *elf, warn("%s: section mismatch in reference: %s (section: %s) -> %s (section: %s)\n", modname, fromsym, fromsec, tosym, tosec); break; - case EXPORT_TO_INIT_EXIT: - warn("%s: EXPORT_SYMBOL used for init/exit symbol: %s (section: %s)\n", - modname, tosym, tosec); - break; case EXTABLE_TO_NON_TEXT: warn("%s(%s+0x%lx): Section mismatch in reference to the %s:%s\n", modname, fromsec, (long)faddr, tosec, tosym); @@ -1229,14 +1209,69 @@ static void default_mismatch_handler(const char *modname, struct elf_info *elf, } } +static void check_export_symbol(struct module *mod, struct elf_info *elf, + Elf_Addr faddr, const char *secname, + Elf_Sym *sym) +{ + const char *label_name, *name, *prefix; + Elf_Sym *label; + struct symbol *s; + bool is_gpl; + + label = find_fromsym(elf, faddr, elf->export_symbol_secndx); + label_name = sym_name(elf, label); + + name = sym_name(elf, sym); + + if (strstarts(label_name, "__export_symbol_gpl_")) { + prefix = "__export_symbol_gpl_"; + is_gpl = true; + } else if (strstarts(label_name, "__export_symbol__")) { + prefix = "__export_symbol__"; + is_gpl = false; + } else { + error("%s: .export_symbol section contains strange symbol '%s'\n", + mod->name, label_name); + return; + } + + if (strcmp(label_name + strlen(prefix), name)) { + error("%s: .export_symbol section references '%s', but it does not seem to be an export symbol\n", + mod->name, name); + return; + } + + s = sym_add_exported(name, mod, is_gpl); + sym_update_namespace(name, sym_get_data(elf, label)); + + /* + * We need to be aware whether we are exporting a function or + * a data on some architectures. + */ + s->is_func = (ELF_ST_TYPE(sym->st_info) == STT_FUNC); + + if (match(secname, PATTERNS(INIT_SECTIONS))) + error("%s: %s: EXPORT_SYMBOL used for init symbol. Remove __init or EXPORT_SYMBOL.\n", + mod->name, name); + else if (match(secname, PATTERNS(EXIT_SECTIONS))) + error("%s: %s: EXPORT_SYMBOL used for exit symbol. Remove __exit or EXPORT_SYMBOL.\n", + mod->name, name); +} + static void check_section_mismatch(struct module *mod, struct elf_info *elf, Elf_Sym *sym, unsigned int fsecndx, const char *fromsec, Elf_Addr faddr, Elf_Addr taddr) { const char *tosec = sec_name(elf, get_secindex(elf, sym)); - const struct sectioncheck *mismatch = section_mismatch(fromsec, tosec); + const struct sectioncheck *mismatch; + if (elf->export_symbol_secndx == fsecndx) { + check_export_symbol(mod, elf, faddr, tosec, sym); + return; + } + + mismatch = section_mismatch(fromsec, tosec); if (!mismatch) return; @@ -1650,15 +1685,6 @@ static void read_symbols(const char *modname) handle_moddevtable(mod, &info, sym, symname); } - for (sym = info.symtab_start; sym < info.symtab_stop; sym++) { - symname = remove_dot(info.strtab + sym->st_name); - - /* Apply symbol namespaces from __kstrtabns_ entries. */ - if (strstarts(symname, "__kstrtabns_")) - sym_update_namespace(symname + strlen("__kstrtabns_"), - sym_get_data(&info, sym)); - } - check_sec_ref(mod, &info); if (!mod->is_vmlinux) { @@ -1842,6 +1868,14 @@ static void add_exported_symbols(struct buffer *buf, struct module *mod) { struct symbol *sym; + /* generate struct for exported symbols */ + buf_printf(buf, "\n"); + list_for_each_entry(sym, &mod->exported_symbols, list) + buf_printf(buf, "KSYMTAB_%s(%s, \"%s\", \"%s\");\n", + sym->is_func ? "FUNC" : "DATA", sym->name, + sym->is_gpl_only ? "_gpl" : "", + sym->namespace ?: ""); + if (!modversions) return; diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h index b1e2d95f8047..dfdb9484e325 100644 --- a/scripts/mod/modpost.h +++ b/scripts/mod/modpost.h @@ -137,6 +137,7 @@ struct elf_info { Elf_Shdr *sechdrs; Elf_Sym *symtab_start; Elf_Sym *symtab_stop; + unsigned int export_symbol_secndx; /* .export_symbol section */ char *strtab; char *modinfo; unsigned int modinfo_len; From patchwork Sun May 21 16:04:16 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masahiro Yamada X-Patchwork-Id: 13249443 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 63789C7EE2D for ; Sun, 21 May 2023 16:06:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230412AbjEUQGF (ORCPT ); Sun, 21 May 2023 12:06:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55818 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230413AbjEUQFx (ORCPT ); Sun, 21 May 2023 12:05:53 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E0E92E40; Sun, 21 May 2023 09:05:35 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 0091D6176E; Sun, 21 May 2023 16:05:35 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0700DC4339B; Sun, 21 May 2023 16:05:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1684685134; bh=Kep8Iw8VgQxgpYvfyniHHN0kmqkyl1ojVYpvdIK/Gqw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Bdsxo0Bnw0VsHYH2A6RveJVq545eSK9UN1ptiHxy3Olr2UVrZOeL7GE8eshxkxXw8 GuTK84yMkhgrgLPArlwIKohU2AY10Bg26A6+jAW009prjL5jNl6irkffuTwXIo8baR n40yFR7n6qvHgdJ1izX+FxPWLYM5h9RjCp3vQtFSd1tFYoPSXqwvCN76vAZFZe8lH5 q6X8LWeMEreOU/ldpCKcsA0IqAZ1XAadqSmrQ4++aXn7ljs485xu+wUeszcPPZCxpA o8JnB1AfzenNyxFXHBDt1mAUf7nC7VIlK5Z+TSKRFDBgln4GtbcARyJJH3xqY+xNSk W0HaGJxEvUGSA== From: Masahiro Yamada To: linux-kbuild@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Nathan Chancellor , Nick Desaulniers , Nicolas Schier , Masahiro Yamada Subject: [PATCH v6 11/20] ia64,export.h: replace EXPORT_DATA_SYMBOL* with EXPORT_SYMBOL* Date: Mon, 22 May 2023 01:04:16 +0900 Message-Id: <20230521160426.1881124-12-masahiroy@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230521160426.1881124-1-masahiroy@kernel.org> References: <20230521160426.1881124-1-masahiroy@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org With the previous refactoring, you can always use EXPORT_SYMBOL*. Replace two instances in ia64, then remove EXPORT_DATA_SYMBOL*. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- arch/ia64/kernel/head.S | 2 +- arch/ia64/kernel/ivt.S | 2 +- include/asm-generic/export.h | 3 --- 3 files changed, 2 insertions(+), 5 deletions(-) diff --git a/arch/ia64/kernel/head.S b/arch/ia64/kernel/head.S index f22469f1c1fc..c096500590e9 100644 --- a/arch/ia64/kernel/head.S +++ b/arch/ia64/kernel/head.S @@ -170,7 +170,7 @@ RestRR: \ __PAGE_ALIGNED_DATA .global empty_zero_page -EXPORT_DATA_SYMBOL_GPL(empty_zero_page) +EXPORT_SYMBOL_GPL(empty_zero_page) empty_zero_page: .skip PAGE_SIZE diff --git a/arch/ia64/kernel/ivt.S b/arch/ia64/kernel/ivt.S index d6d4229b28db..7a418e324d30 100644 --- a/arch/ia64/kernel/ivt.S +++ b/arch/ia64/kernel/ivt.S @@ -87,7 +87,7 @@ .align 32768 // align on 32KB boundary .global ia64_ivt - EXPORT_DATA_SYMBOL(ia64_ivt) + EXPORT_SYMBOL(ia64_ivt) ia64_ivt: ///////////////////////////////////////////////////////////////////////////////////////// // 0x0000 Entry 0 (size 64 bundles) VHPT Translation (8,20,47) diff --git a/include/asm-generic/export.h b/include/asm-generic/export.h index 0ae9f38a904c..570cd4da7210 100644 --- a/include/asm-generic/export.h +++ b/include/asm-generic/export.h @@ -8,7 +8,4 @@ */ #include -#define EXPORT_DATA_SYMBOL(name) EXPORT_SYMBOL(name) -#define EXPORT_DATA_SYMBOL_GPL(name) EXPORT_SYMBOL_GPL(name) - #endif From patchwork Sun May 21 16:04:17 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masahiro Yamada X-Patchwork-Id: 13249444 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1629CC77B73 for ; Sun, 21 May 2023 16:06:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230199AbjEUQGW (ORCPT ); Sun, 21 May 2023 12:06:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55924 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230271AbjEUQGB (ORCPT ); Sun, 21 May 2023 12:06:01 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C31E3E5D; Sun, 21 May 2023 09:05:37 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id D215960F36; Sun, 21 May 2023 16:05:36 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D8005C4339C; Sun, 21 May 2023 16:05:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1684685136; bh=8xXXD40CCdpBx0TDe2iS4cr/q8YTKMQjxzKZ7hNzzQ4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=h9mDjJ7J4lr2ROglAloh48hlNF4fA1j6VJvfm4RcIGCU41B5x429jRTDCqPCspt4B R44aIg1TLHWguzW6fWzS0gfOu8+GzfWd1Ch5JUlMuHe6Tvuj4XwkiGhUS/LcAJ6hQQ GfKwKKgdjOGm9IPqRS/3ujlh0A4TJpgfVALf9BMQzrmrzHIUfYZwapP/ecPP966Vlz Ls4J8A24RpX3f7tiGX/5fApvWiz3ykHBpIdBMtS2pRolKhNV+6czzLjCn17VB9PzUq q6jSc2ebQd9l5Y90yr4+Oxm56sulIn3HRtpecRYBE+vqD4xbYEueZ/s+xyIcSXcFs3 WeI+e5pz0axYw== From: Masahiro Yamada To: linux-kbuild@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Nathan Chancellor , Nick Desaulniers , Nicolas Schier , Masahiro Yamada Subject: [PATCH v6 12/20] modpost: check static EXPORT_SYMBOL* by modpost again Date: Mon, 22 May 2023 01:04:17 +0900 Message-Id: <20230521160426.1881124-13-masahiroy@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230521160426.1881124-1-masahiroy@kernel.org> References: <20230521160426.1881124-1-masahiroy@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org Commit 31cb50b5590f ("kbuild: check static EXPORT_SYMBOL* by script instead of modpost") moved the static EXPORT_SYMBOL* check from the mostpost to a shell script because I thought it must be checked per compilation unit to avoid false negatives. I came up with an idea to do this in modpost, against combined ELF files. The relocation entries in ELF will find the correct exported symbol even if there exist symbols with the same name in different compilation units. Again, the same sample code. Makefile: obj-y += foo1.o foo2.o foo1.c: #include static void foo(void) {} EXPORT_SYMBOL(foo); foo2.c: void foo(void) {} Then, modpost can catch it correctly. MODPOST Module.symvers ERROR: modpost: vmlinux: local symbol 'foo' was exported Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- Changes in v6: - Make the symbol name in the warning more precise scripts/Makefile.build | 4 --- scripts/check-local-export | 70 -------------------------------------- scripts/mod/modpost.c | 7 ++++ 3 files changed, 7 insertions(+), 74 deletions(-) delete mode 100755 scripts/check-local-export diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 6bf026a304e4..bd4123795299 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -220,8 +220,6 @@ cmd_gen_ksymdeps = \ $(CONFIG_SHELL) $(srctree)/scripts/gen_ksymdeps.sh $@ >> $(dot-target).cmd endif -cmd_check_local_export = $(srctree)/scripts/check-local-export $@ - ifneq ($(findstring 1, $(KBUILD_EXTRA_WARN)),) cmd_warn_shared_object = $(if $(word 2, $(modname-multi)),$(warning $(kbuild-file): $*.o is added to multiple modules: $(modname-multi))) endif @@ -229,7 +227,6 @@ endif define rule_cc_o_c $(call cmd_and_fixdep,cc_o_c) $(call cmd,gen_ksymdeps) - $(call cmd,check_local_export) $(call cmd,checksrc) $(call cmd,checkdoc) $(call cmd,gen_objtooldep) @@ -241,7 +238,6 @@ endef define rule_as_o_S $(call cmd_and_fixdep,as_o_S) $(call cmd,gen_ksymdeps) - $(call cmd,check_local_export) $(call cmd,gen_objtooldep) $(call cmd,gen_symversions_S) $(call cmd,warn_shared_object) diff --git a/scripts/check-local-export b/scripts/check-local-export deleted file mode 100755 index 969a313b9299..000000000000 --- a/scripts/check-local-export +++ /dev/null @@ -1,70 +0,0 @@ -#!/bin/sh -# SPDX-License-Identifier: GPL-2.0-only -# -# Copyright (C) 2022 Masahiro Yamada -# Copyright (C) 2022 Owen Rafferty -# -# Exit with error if a local exported symbol is found. -# EXPORT_SYMBOL should be used for global symbols. - -set -e -pid=$$ - -# If there is no symbol in the object, ${NM} (both GNU nm and llvm-nm) shows -# 'no symbols' diagnostic (but exits with 0). It is harmless and hidden by -# '2>/dev/null'. However, it suppresses real error messages as well. Add a -# hand-crafted error message here. -# -# TODO: -# Use --quiet instead of 2>/dev/null when we upgrade the minimum version of -# binutils to 2.37, llvm to 13.0.0. -# Then, the following line will be simpler: -# { ${NM} --quiet ${1} || kill 0; } | - -{ ${NM} ${1} 2>/dev/null || { echo "${0}: ${NM} failed" >&2; kill $pid; } } | -${AWK} -v "file=${1}" ' -BEGIN { - i = 0 -} - -# Skip the line if the number of fields is less than 3. -# -# case 1) -# For undefined symbols, the first field (value) is empty. -# The outout looks like this: -# " U _printk" -# It is unneeded to record undefined symbols. -# -# case 2) -# For Clang LTO, llvm-nm outputs a line with type t but empty name: -# "---------------- t" -!length($3) { - next -} - -# save (name, type) in the associative array -{ symbol_types[$3]=$2 } - -# append the exported symbol to the array -($3 ~ /^__export_symbol_(gpl)?_.*/) { - export_symbols[i] = $3 - sub(/^__export_symbol_(gpl)?_/, "", export_symbols[i]) - i++ -} - -END { - exit_code = 0 - for (j = 0; j < i; ++j) { - name = export_symbols[j] - # nm(3) says "If lowercase, the symbol is usually local" - if (symbol_types[name] ~ /[a-z]/) { - printf "%s: error: local symbol %s was exported\n", - file, name | "cat 1>&2" - exit_code = 1 - } - } - - exit exit_code -}' - -exit $? diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 8b94090d0743..dd1d066f1214 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -1235,6 +1235,13 @@ static void check_export_symbol(struct module *mod, struct elf_info *elf, return; } + if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL && + ELF_ST_BIND(sym->st_info) != STB_WEAK) { + error("%s: local symbol '%s' was exported\n", mod->name, + label_name + strlen(prefix)); + return; + } + if (strcmp(label_name + strlen(prefix), name)) { error("%s: .export_symbol section references '%s', but it does not seem to be an export symbol\n", mod->name, name); From patchwork Sun May 21 16:04:18 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masahiro Yamada X-Patchwork-Id: 13249446 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 71CB1C77B73 for ; Sun, 21 May 2023 16:06:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231216AbjEUQGa (ORCPT ); Sun, 21 May 2023 12:06:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55622 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231151AbjEUQGI (ORCPT ); Sun, 21 May 2023 12:06:08 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 20248118; Sun, 21 May 2023 09:05:45 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id C0F7E60FAC; Sun, 21 May 2023 16:05:38 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B1D51C433EF; Sun, 21 May 2023 16:05:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1684685138; bh=Irn8s+5UgFMeFebwkxke8zqHLikSaF4AyAgWT+2aYBE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ICceVZTSu3z1ir8GvjVJApiD7PzYwHGmFkdrP3xw09UR2BaYM/a7LEpWIbLe77eJu CWePIZBTSUFLEftBlphUFf0dM+h4pVQwgxQB8fKjva4Z01zyFcJmfVzbVv9Hni2LrN JSBRR6cAgbEawSyRab65dt05G4F/Y1L/uPldOeo6PIeJQ7BhsSldm1U/JPmdg06J6k xUImyjm7tmBjAAydWlh/gwCtW0Y7l/9R1/JMjjFC+jda/UVdaOoNwAybEslC3+y8O9 rahLv5afZUy2nIJ8DoYolXGrJBvskFiPdBCTUcvgZZFEwRyVSZlNJy68PByKwPpCJ2 7et/6ExVxDJmg== From: Masahiro Yamada To: linux-kbuild@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Nathan Chancellor , Nick Desaulniers , Nicolas Schier , Masahiro Yamada Subject: [PATCH v6 13/20] modpost: squash sym_update_namespace() into sym_add_exported() Date: Mon, 22 May 2023 01:04:18 +0900 Message-Id: <20230521160426.1881124-14-masahiroy@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230521160426.1881124-1-masahiroy@kernel.org> References: <20230521160426.1881124-1-masahiroy@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org Pass a set of the name, license, and namespace to sym_add_exported(). sym_update_namespace() is unneeded. Reviewed-by: Nick Desaulniers Signed-off-by: Masahiro Yamada --- scripts/mod/modpost.c | 27 ++++----------------------- 1 file changed, 4 insertions(+), 23 deletions(-) diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index dd1d066f1214..8fe2aa7bf71b 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -353,26 +353,8 @@ static const char *sec_name(const struct elf_info *info, unsigned int secindex) #define strstarts(str, prefix) (strncmp(str, prefix, strlen(prefix)) == 0) -static void sym_update_namespace(const char *symname, const char *namespace) -{ - struct symbol *s = find_symbol(symname); - - /* - * That symbol should have been created earlier and thus this is - * actually an assertion. - */ - if (!s) { - error("Could not update namespace(%s) for symbol %s\n", - namespace, symname); - return; - } - - free(s->namespace); - s->namespace = namespace[0] ? NOFAIL(strdup(namespace)) : NULL; -} - static struct symbol *sym_add_exported(const char *name, struct module *mod, - bool gpl_only) + bool gpl_only, const char *namespace) { struct symbol *s = find_symbol(name); @@ -385,6 +367,7 @@ static struct symbol *sym_add_exported(const char *name, struct module *mod, s = alloc_symbol(name); s->module = mod; s->is_gpl_only = gpl_only; + s->namespace = namespace[0] ? NOFAIL(strdup(namespace)) : NULL; list_add_tail(&s->list, &mod->exported_symbols); hash_add_symbol(s); @@ -1248,8 +1231,7 @@ static void check_export_symbol(struct module *mod, struct elf_info *elf, return; } - s = sym_add_exported(name, mod, is_gpl); - sym_update_namespace(name, sym_get_data(elf, label)); + s = sym_add_exported(name, mod, is_gpl, sym_get_data(elf, label)); /* * We need to be aware whether we are exporting a function or @@ -2126,9 +2108,8 @@ static void read_dump(const char *fname) mod = new_module(modname, strlen(modname)); mod->from_dump = true; } - s = sym_add_exported(symname, mod, gpl_only); + s = sym_add_exported(symname, mod, gpl_only, namespace); sym_set_crc(s, crc); - sym_update_namespace(symname, namespace); } free(buf); return; From patchwork Sun May 21 16:04:19 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masahiro Yamada X-Patchwork-Id: 13249445 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2E97CC77B7C for ; Sun, 21 May 2023 16:06:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230456AbjEUQGY (ORCPT ); Sun, 21 May 2023 12:06:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55722 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230317AbjEUQGE (ORCPT ); Sun, 21 May 2023 12:06:04 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B0520EB; Sun, 21 May 2023 09:05:40 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 8FF6D60FE4; Sun, 21 May 2023 16:05:40 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A442DC433D2; Sun, 21 May 2023 16:05:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1684685140; bh=u+zekrJ6wRjbNqFFVUdlRa3NbSgsRSQhW8QM+KPUZv0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=daYmpNE8SBeBg/ncLjgrQX9hXUf8/Lr9PN8CKnk4v3neIok3ZPyDUY7NzXonPybof XVD2vdCsX+X6tdAqTYYBCYcRpI7608VLhV8bXM3o9bqd4AIL9ori+mIyCRjAPshsOF krHNx/gPTeOSLWUOoRCVXDNOELmcK5E+xU4O4R48frBglEOg7GLuzqCyUW69jNGIyK RRTe7rqacylkQdPbhaiEcou9cBTuD0zppV77pqcbfK/Xp7yRUEi7Bcl8cyEpYY1It6 f8I+NxTFj0uDCP+YfceEEEQ6da6VicV8R+0cxV99ZJEa9J4sUUefuzpRoEeUmWiXqT oTgSCHXaobIoQ== From: Masahiro Yamada To: linux-kbuild@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Nathan Chancellor , Nick Desaulniers , Nicolas Schier , Masahiro Yamada Subject: [PATCH v6 14/20] modpost: use null string instead of NULL pointer for default namespace Date: Mon, 22 May 2023 01:04:19 +0900 Message-Id: <20230521160426.1881124-15-masahiroy@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230521160426.1881124-1-masahiroy@kernel.org> References: <20230521160426.1881124-1-masahiroy@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org The default namespace is the null string, "". When set, the null string "" is converted to NULL: s->namespace = namespace[0] ? NOFAIL(strdup(namespace)) : NULL; When printed, the NULL pointer is get back to the null string: sym->namespace ?: "" This saves 1 byte memory allocated for "", but loses the readability. In kernel-space, we strive to save memory, but modpost is a userspace tool used to build the kernel. On modern systems, such small piece of memory is not a big deal. Handle the namespace string as is. Reviewed-by: Nick Desaulniers Signed-off-by: Masahiro Yamada --- scripts/mod/modpost.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 8fe2aa7bf71b..f14fe9301ae6 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -298,6 +298,13 @@ static bool contains_namespace(struct list_head *head, const char *namespace) { struct namespace_list *list; + /* + * The default namespace is null string "", which is always implicitly + * contained. + */ + if (!namespace[0]) + return true; + list_for_each_entry(list, head, list) { if (!strcmp(list->namespace, namespace)) return true; @@ -367,7 +374,7 @@ static struct symbol *sym_add_exported(const char *name, struct module *mod, s = alloc_symbol(name); s->module = mod; s->is_gpl_only = gpl_only; - s->namespace = namespace[0] ? NOFAIL(strdup(namespace)) : NULL; + s->namespace = NOFAIL(strdup(namespace)); list_add_tail(&s->list, &mod->exported_symbols); hash_add_symbol(s); @@ -1775,8 +1782,7 @@ static void check_exports(struct module *mod) else basename = mod->name; - if (exp->namespace && - !contains_namespace(&mod->imported_namespaces, exp->namespace)) { + if (!contains_namespace(&mod->imported_namespaces, exp->namespace)) { modpost_log(allow_missing_ns_imports ? LOG_WARN : LOG_ERROR, "module %s uses symbol %s from namespace %s, but does not import it.\n", basename, exp->name, exp->namespace); @@ -1862,8 +1868,7 @@ static void add_exported_symbols(struct buffer *buf, struct module *mod) list_for_each_entry(sym, &mod->exported_symbols, list) buf_printf(buf, "KSYMTAB_%s(%s, \"%s\", \"%s\");\n", sym->is_func ? "FUNC" : "DATA", sym->name, - sym->is_gpl_only ? "_gpl" : "", - sym->namespace ?: ""); + sym->is_gpl_only ? "_gpl" : "", sym->namespace); if (!modversions) return; @@ -2131,7 +2136,7 @@ static void write_dump(const char *fname) buf_printf(&buf, "0x%08x\t%s\t%s\tEXPORT_SYMBOL%s\t%s\n", sym->crc, sym->name, mod->name, sym->is_gpl_only ? "_GPL" : "", - sym->namespace ?: ""); + sym->namespace); } } write_buf(&buf, fname); From patchwork Sun May 21 16:04:20 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masahiro Yamada X-Patchwork-Id: 13249449 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8B8F8C77B7C for ; Sun, 21 May 2023 16:06:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231204AbjEUQGz (ORCPT ); Sun, 21 May 2023 12:06:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55790 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230405AbjEUQGZ (ORCPT ); Sun, 21 May 2023 12:06:25 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E5590137; Sun, 21 May 2023 09:06:00 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 28F9960ECB; Sun, 21 May 2023 16:05:42 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 675DDC43446; Sun, 21 May 2023 16:05:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1684685141; bh=MhiWna3f1Blsf9LFnRVrVnpUpQ9OSU6bl7WHKsENazc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gxG185MoZzIQAXGheam0QvHFp4pptcCw+wX1o+g6uBARtFlGSFZahIvWE/RJsoUPn h6vkGQ4U3Ed9CT4GbtzdmU83qQfuKIZgOBgZ7bciCy7coh0/4uZN6ORffGLOo4uWUa MDWMqynS1IIfTlZt7IVkr4G2+xon1la6jHICNK8jCNMw1aJ3ozQmoKEp23c/CLB84Y YCYvRgThY9jBapqWSPUigGSDSTkfBUnm0/v/HsbvxU+fK77UOhk4sfEhRzJCwbu3m6 xVMzeVuiUE3NMJqKVUSLzaC3UHhS7XO9uKlwZa+di+UZoKrHYoax0lPkgl2AiOb8O7 YrBfZxcMM5rHQ== From: Masahiro Yamada To: linux-kbuild@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Nathan Chancellor , Nick Desaulniers , Nicolas Schier , Masahiro Yamada Subject: [PATCH v6 15/20] kbuild: implement CONFIG_TRIM_UNUSED_KSYMS without recursion Date: Mon, 22 May 2023 01:04:20 +0900 Message-Id: <20230521160426.1881124-16-masahiroy@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230521160426.1881124-1-masahiroy@kernel.org> References: <20230521160426.1881124-1-masahiroy@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org When CONFIG_TRIM_UNUSED_KSYMS is enabled, Kbuild recursively traverses the directory tree to determine which EXPORT_SYMBOL to trim. If an EXPORT_SYMBOL turns out to be unused by anyone, Kbuild begins the second traverse, where some source files are recompiled with their EXPORT_SYMBOL() tuned into a no-op. Linus stated negative opinions about this slowness in commits: - 5cf0fd591f2e ("Kbuild: disable TRIM_UNUSED_KSYMS option") - a555bdd0c58c ("Kbuild: enable TRIM_UNUSED_KSYMS again, with some guarding") We can do this better now. The final data structures of EXPORT_SYMBOL are generated by the modpost stage, so modpost can selectively emit KSYMTAB entries that are really used by modules. Commit f73edc8951b2 ("kbuild: unify two modpost invocations") is another ground-work to do this in a one-pass algorithm. With the list of modules, modpost sets sym->used if it is used by a module. modpost emits KSYMTAB only for symbols with sym->used==true. BTW, Nicolas explained why the trimming was implemented with recursion: https://lore.kernel.org/all/2o2rpn97-79nq-p7s2-nq5-8p83391473r@syhkavp.arg/ Actually, we never achieved that level of optimization where the chain reaction of trimming comes into play because: - CONFIG_LTO_CLANG cannot remove any unused symbols - CONFIG_LD_DEAD_CODE_DATA_ELIMINATION is enabled only for vmlinux, but not modules If deeper trimming is required, we need to revisit this, but I guess that is unlikely to happen. Signed-off-by: Masahiro Yamada --- Changes in v5: - Clean up more .gitignore | 1 - Makefile | 19 +--------- include/linux/export.h | 65 +++++---------------------------- scripts/Makefile.build | 7 ---- scripts/Makefile.modpost | 7 ++++ scripts/adjust_autoksyms.sh | 73 ------------------------------------- scripts/basic/fixdep.c | 3 +- scripts/gen_ksymdeps.sh | 30 --------------- scripts/mod/modpost.c | 54 ++++++++++++++++++++++++--- scripts/remove-stale-files | 2 + 10 files changed, 70 insertions(+), 191 deletions(-) delete mode 100755 scripts/adjust_autoksyms.sh delete mode 100755 scripts/gen_ksymdeps.sh diff --git a/.gitignore b/.gitignore index 7f86e0837909..172e3874adfd 100644 --- a/.gitignore +++ b/.gitignore @@ -112,7 +112,6 @@ modules.order # /include/config/ /include/generated/ -/include/ksym/ /arch/*/include/generated/ # stgit generated dirs diff --git a/Makefile b/Makefile index f836936fb4d8..ffc2c9b632fd 100644 --- a/Makefile +++ b/Makefile @@ -1193,28 +1193,13 @@ endif export KBUILD_VMLINUX_LIBS export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds -# Recurse until adjust_autoksyms.sh is satisfied -PHONY += autoksyms_recursive ifdef CONFIG_TRIM_UNUSED_KSYMS # For the kernel to actually contain only the needed exported symbols, # we have to build modules as well to determine what those symbols are. # (this can be evaluated only once include/config/auto.conf has been included) KBUILD_MODULES := 1 - -autoksyms_recursive: $(build-dir) modules.order - $(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \ - "$(MAKE) -f $(srctree)/Makefile autoksyms_recursive" endif -autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h) - -quiet_cmd_autoksyms_h = GEN $@ - cmd_autoksyms_h = mkdir -p $(dir $@); \ - $(CONFIG_SHELL) $(srctree)/scripts/gen_autoksyms.sh $@ - -$(autoksyms_h): - $(call cmd,autoksyms_h) - # '$(AR) mPi' needs 'T' to workaround the bug of llvm-ar <= 14 quiet_cmd_ar_vmlinux.a = AR $@ cmd_ar_vmlinux.a = \ @@ -1223,7 +1208,7 @@ quiet_cmd_ar_vmlinux.a = AR $@ $(AR) mPiT $$($(AR) t $@ | sed -n 1p) $@ $$($(AR) t $@ | grep -F -f $(srctree)/scripts/head-object-list.txt) targets += vmlinux.a -vmlinux.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt autoksyms_recursive FORCE +vmlinux.a: $(KBUILD_VMLINUX_OBJS) scripts/head-object-list.txt FORCE $(call if_changed,ar_vmlinux.a) PHONY += vmlinux_o @@ -1279,7 +1264,7 @@ scripts: scripts_basic scripts_dtc PHONY += prepare archprepare archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \ - asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h \ + asm-generic $(version_h) include/generated/utsrelease.h \ include/generated/compile.h include/generated/autoconf.h remove-stale-files prepare0: archprepare diff --git a/include/linux/export.h b/include/linux/export.h index 32461a01608c..9bf081ff9903 100644 --- a/include/linux/export.h +++ b/include/linux/export.h @@ -37,30 +37,13 @@ extern struct module __this_module; #define __EXPORT_SYMBOL_REF(sym) .balign 4; .long sym #endif -#define ____EXPORT_SYMBOL(sym, license, ns) \ +#define ___EXPORT_SYMBOL(sym, license, ns) \ .section ".export_symbol","a" ; \ __export_symbol_##license##_##sym: ; \ .asciz ns ; \ __EXPORT_SYMBOL_REF(sym) ; \ .previous -#ifdef __GENKSYMS__ - -#define ___EXPORT_SYMBOL(sym, sec, ns) __GENKSYMS_EXPORT_SYMBOL(sym) - -#elif defined(__ASSEMBLY__) - -#define ___EXPORT_SYMBOL(sym, license, ns) \ - ____EXPORT_SYMBOL(sym, license, ns) - -#else - -#define ___EXPORT_SYMBOL(sym, license, ns) \ - __ADDRESSABLE(sym) \ - asm(__stringify(____EXPORT_SYMBOL(sym, license, ns))) - -#endif - #if !defined(CONFIG_MODULES) || defined(__DISABLE_EXPORTS) /* @@ -70,50 +53,20 @@ extern struct module __this_module; */ #define __EXPORT_SYMBOL(sym, sec, ns) -#elif defined(CONFIG_TRIM_UNUSED_KSYMS) +#elif defined(__GENKSYMS__) -#include +#define __EXPORT_SYMBOL(sym, sec, ns) __GENKSYMS_EXPORT_SYMBOL(sym) -/* - * For fine grained build dependencies, we want to tell the build system - * about each possible exported symbol even if they're not actually exported. - * We use a symbol pattern __ksym_marker_ that the build system filters - * from the $(NM) output (see scripts/gen_ksymdeps.sh). These symbols are - * discarded in the final link stage. - */ +#elif defined(__ASSEMBLY__) -#ifdef __ASSEMBLY__ - -#define __ksym_marker(sym) \ - .section ".discard.ksym","a" ; \ -__ksym_marker_##sym: ; \ - .previous +#define __EXPORT_SYMBOL(sym, license, ns) \ + ___EXPORT_SYMBOL(sym, license, ns) #else -#define __ksym_marker(sym) \ - static int __ksym_marker_##sym[0] __section(".discard.ksym") __used - -#endif - -#define __EXPORT_SYMBOL(sym, sec, ns) \ - __ksym_marker(sym); \ - __cond_export_sym(sym, sec, ns, __is_defined(__KSYM_##sym)) -#define __cond_export_sym(sym, sec, ns, conf) \ - ___cond_export_sym(sym, sec, ns, conf) -#define ___cond_export_sym(sym, sec, ns, enabled) \ - __cond_export_sym_##enabled(sym, sec, ns) -#define __cond_export_sym_1(sym, sec, ns) ___EXPORT_SYMBOL(sym, sec, ns) - -#ifdef __GENKSYMS__ -#define __cond_export_sym_0(sym, sec, ns) __GENKSYMS_EXPORT_SYMBOL(sym) -#else -#define __cond_export_sym_0(sym, sec, ns) /* nothing */ -#endif - -#else - -#define __EXPORT_SYMBOL(sym, sec, ns) ___EXPORT_SYMBOL(sym, sec, ns) +#define __EXPORT_SYMBOL(sym, license, ns) \ + __ADDRESSABLE(sym) \ + asm(__stringify(___EXPORT_SYMBOL(sym, license, ns))) #endif /* CONFIG_MODULES */ diff --git a/scripts/Makefile.build b/scripts/Makefile.build index bd4123795299..8154bd962eea 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -215,18 +215,12 @@ is-standard-object = $(if $(filter-out y%, $(OBJECT_FILES_NON_STANDARD_$(basetar $(obj)/%.o: objtool-enabled = $(if $(is-standard-object),$(if $(delay-objtool),$(is-single-obj-m),y)) -ifdef CONFIG_TRIM_UNUSED_KSYMS -cmd_gen_ksymdeps = \ - $(CONFIG_SHELL) $(srctree)/scripts/gen_ksymdeps.sh $@ >> $(dot-target).cmd -endif - ifneq ($(findstring 1, $(KBUILD_EXTRA_WARN)),) cmd_warn_shared_object = $(if $(word 2, $(modname-multi)),$(warning $(kbuild-file): $*.o is added to multiple modules: $(modname-multi))) endif define rule_cc_o_c $(call cmd_and_fixdep,cc_o_c) - $(call cmd,gen_ksymdeps) $(call cmd,checksrc) $(call cmd,checkdoc) $(call cmd,gen_objtooldep) @@ -237,7 +231,6 @@ endef define rule_as_o_S $(call cmd_and_fixdep,as_o_S) - $(call cmd,gen_ksymdeps) $(call cmd,gen_objtooldep) $(call cmd,gen_symversions_S) $(call cmd,warn_shared_object) diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost index 0980c58d8afc..1e0b47cbabd9 100644 --- a/scripts/Makefile.modpost +++ b/scripts/Makefile.modpost @@ -90,6 +90,13 @@ targets += .vmlinux.objs .vmlinux.objs: vmlinux.a $(KBUILD_VMLINUX_LIBS) FORCE $(call if_changed,vmlinux_objs) +ifdef CONFIG_TRIM_UNUSED_KSYMS +ksym-wl := $(CONFIG_UNUSED_KSYMS_WHITELIST) +ksym-wl := $(if $(filter-out /%, $(ksym-wl)),$(srctree)/)$(ksym-wl) +modpost-args += -t $(addprefix -W, $(ksym-wl)) +modpost-deps += $(ksym-wl) +endif + ifeq ($(wildcard vmlinux.o),) missing-input := vmlinux.o output-symdump := modules-only.symvers diff --git a/scripts/adjust_autoksyms.sh b/scripts/adjust_autoksyms.sh deleted file mode 100755 index f1b5ac818411..000000000000 --- a/scripts/adjust_autoksyms.sh +++ /dev/null @@ -1,73 +0,0 @@ -#!/bin/sh -# SPDX-License-Identifier: GPL-2.0-only - -# Script to update include/generated/autoksyms.h and dependency files -# -# Copyright: (C) 2016 Linaro Limited -# Created by: Nicolas Pitre, January 2016 -# - -# Update the include/generated/autoksyms.h file. -# -# For each symbol being added or removed, the corresponding dependency -# file's timestamp is updated to force a rebuild of the affected source -# file. All arguments passed to this script are assumed to be a command -# to be exec'd to trigger a rebuild of those files. - -set -e - -cur_ksyms_file="include/generated/autoksyms.h" -new_ksyms_file="include/generated/autoksyms.h.tmpnew" - -info() { - if [ "$quiet" != "silent_" ]; then - printf " %-7s %s\n" "$1" "$2" - fi -} - -info "CHK" "$cur_ksyms_file" - -# Use "make V=1" to debug this script. -case "$KBUILD_VERBOSE" in -*1*) - set -x - ;; -esac - -# Generate a new symbol list file -$CONFIG_SHELL $srctree/scripts/gen_autoksyms.sh --modorder "$new_ksyms_file" - -# Extract changes between old and new list and touch corresponding -# dependency files. -changed=$( -count=0 -sort "$cur_ksyms_file" "$new_ksyms_file" | uniq -u | -sed -n 's/^#define __KSYM_\(.*\) 1/\1/p' | -while read sympath; do - if [ -z "$sympath" ]; then continue; fi - depfile="include/ksym/${sympath}" - mkdir -p "$(dirname "$depfile")" - touch "$depfile" - # Filesystems with coarse time precision may create timestamps - # equal to the one from a file that was very recently built and that - # needs to be rebuild. Let's guard against that by making sure our - # dep files are always newer than the first file we created here. - while [ ! "$depfile" -nt "$new_ksyms_file" ]; do - touch "$depfile" - done - echo $((count += 1)) -done | tail -1 ) -changed=${changed:-0} - -if [ $changed -gt 0 ]; then - # Replace the old list with tne new one - old=$(grep -c "^#define __KSYM_" "$cur_ksyms_file" || true) - new=$(grep -c "^#define __KSYM_" "$new_ksyms_file" || true) - info "KSYMS" "symbols: before=$old, after=$new, changed=$changed" - info "UPD" "$cur_ksyms_file" - mv -f "$new_ksyms_file" "$cur_ksyms_file" - # Then trigger a rebuild of affected source files - exec $@ -else - rm -f "$new_ksyms_file" -fi diff --git a/scripts/basic/fixdep.c b/scripts/basic/fixdep.c index fa562806c2be..84b6efa849f4 100644 --- a/scripts/basic/fixdep.c +++ b/scripts/basic/fixdep.c @@ -246,8 +246,7 @@ static void *read_file(const char *filename) /* Ignore certain dependencies */ static int is_ignored_file(const char *s, int len) { - return str_ends_with(s, len, "include/generated/autoconf.h") || - str_ends_with(s, len, "include/generated/autoksyms.h"); + return str_ends_with(s, len, "include/generated/autoconf.h"); } /* Do not parse these files */ diff --git a/scripts/gen_ksymdeps.sh b/scripts/gen_ksymdeps.sh deleted file mode 100755 index 8ee533f33659..000000000000 --- a/scripts/gen_ksymdeps.sh +++ /dev/null @@ -1,30 +0,0 @@ -#!/bin/sh -# SPDX-License-Identifier: GPL-2.0 - -set -e - -# List of exported symbols -# -# If the object has no symbol, $NM warns 'no symbols'. -# Suppress the stderr. -# TODO: -# Use -q instead of 2>/dev/null when we upgrade the minimum version of -# binutils to 2.37, llvm to 13.0.0. -ksyms=$($NM $1 2>/dev/null | sed -n 's/.*__ksym_marker_\(.*\)/\1/p') - -if [ -z "$ksyms" ]; then - exit 0 -fi - -echo -echo "ksymdeps_$1 := \\" - -for s in $ksyms -do - printf ' $(wildcard include/ksym/%s) \\\n' "$s" -done - -echo -echo "$1: \$(ksymdeps_$1)" -echo -echo "\$(ksymdeps_$1):" diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index f14fe9301ae6..516323c3910a 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -35,6 +35,9 @@ static bool warn_unresolved; static int sec_mismatch_count; static bool sec_mismatch_warn_only = true; +/* Trim EXPORT_SYMBOLs that are unused by in-tree modules */ +static bool trim_unused_exports; + /* ignore missing files */ static bool ignore_missing_files; /* If set to 1, only warn (instead of error) about missing ns imports */ @@ -217,6 +220,7 @@ struct symbol { bool weak; bool is_func; bool is_gpl_only; /* exported by EXPORT_SYMBOL_GPL */ + bool used; /* there exists a user of this symbol */ char name[]; }; @@ -1772,6 +1776,7 @@ static void check_exports(struct module *mod) continue; } + exp->used = true; s->module = exp->module; s->crc_valid = exp->crc_valid; s->crc = exp->crc; @@ -1795,6 +1800,23 @@ static void check_exports(struct module *mod) } } +static void handle_white_list_exports(const char *white_list) +{ + char *buf, *p, *name; + + buf = read_text_file(white_list); + p = buf; + + while ((name = strsep(&p, "\n"))) { + struct symbol *sym = find_symbol(name); + + if (sym) + sym->used = true; + } + + free(buf); +} + static void check_modname_len(struct module *mod) { const char *mod_name; @@ -1865,10 +1887,14 @@ static void add_exported_symbols(struct buffer *buf, struct module *mod) /* generate struct for exported symbols */ buf_printf(buf, "\n"); - list_for_each_entry(sym, &mod->exported_symbols, list) + list_for_each_entry(sym, &mod->exported_symbols, list) { + if (trim_unused_exports && !sym->used) + continue; + buf_printf(buf, "KSYMTAB_%s(%s, \"%s\", \"%s\");\n", sym->is_func ? "FUNC" : "DATA", sym->name, sym->is_gpl_only ? "_gpl" : "", sym->namespace); + } if (!modversions) return; @@ -1876,6 +1902,9 @@ static void add_exported_symbols(struct buffer *buf, struct module *mod) /* record CRCs for exported symbols */ buf_printf(buf, "\n"); list_for_each_entry(sym, &mod->exported_symbols, list) { + if (trim_unused_exports && !sym->used) + continue; + if (!sym->crc_valid) warn("EXPORT symbol \"%s\" [%s%s] version generation failed, symbol will not be versioned.\n" "Is \"%s\" prototyped in ?\n", @@ -2039,9 +2068,6 @@ static void write_mod_c_file(struct module *mod) char fname[PATH_MAX]; int ret; - check_modname_len(mod); - check_exports(mod); - add_header(&buf, mod); add_exported_symbols(&buf, mod); add_versions(&buf, mod); @@ -2175,12 +2201,13 @@ int main(int argc, char **argv) { struct module *mod; char *missing_namespace_deps = NULL; + char *unused_exports_white_list = NULL; char *dump_write = NULL, *files_source = NULL; int opt; LIST_HEAD(dump_lists); struct dump_list *dl, *dl2; - while ((opt = getopt(argc, argv, "ei:mnT:o:awENd:")) != -1) { + while ((opt = getopt(argc, argv, "ei:mntT:tW:o:awENd:")) != -1) { switch (opt) { case 'e': external_module = true; @@ -2205,6 +2232,12 @@ int main(int argc, char **argv) case 'T': files_source = optarg; break; + case 't': + trim_unused_exports = true; + break; + case 'W': + unused_exports_white_list = optarg; + break; case 'w': warn_unresolved = true; break; @@ -2234,6 +2267,17 @@ int main(int argc, char **argv) if (files_source) read_symbols_from_files(files_source); + list_for_each_entry(mod, &modules, list) { + if (mod->from_dump || mod->is_vmlinux) + continue; + + check_modname_len(mod); + check_exports(mod); + } + + if (unused_exports_white_list) + handle_white_list_exports(unused_exports_white_list); + list_for_each_entry(mod, &modules, list) { if (mod->from_dump) continue; diff --git a/scripts/remove-stale-files b/scripts/remove-stale-files index 7f432900671a..8502a17d47df 100755 --- a/scripts/remove-stale-files +++ b/scripts/remove-stale-files @@ -33,3 +33,5 @@ rm -f rust/target.json rm -f scripts/bin2c rm -f .scmversion + +rm -rf include/ksym From patchwork Sun May 21 16:04:21 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masahiro Yamada X-Patchwork-Id: 13249450 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 98791C77B7C for ; Sun, 21 May 2023 16:07:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231190AbjEUQHK (ORCPT ); Sun, 21 May 2023 12:07:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55692 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230440AbjEUQGw (ORCPT ); Sun, 21 May 2023 12:06:52 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 01C43E4D; Sun, 21 May 2023 09:06:23 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id D172B60FAD; Sun, 21 May 2023 16:05:43 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 015A6C433D2; Sun, 21 May 2023 16:05:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1684685143; bh=UCxWVP1nuNc6iMk2c0zIdYZdTpbk+vNBDxDtYz2nqM8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VZxcDvhQWtgvKJnXTh0+9V9aHQpoBj+bUPS1D6Ckb3zGeMTReJZWF6EzEgQLFKnx6 zzy+3ZWD0NtVMA+yJ1127F4fsAHl60c3NSv9BBfnvxPp7uQCURR5J2D2wr63F1gcoj ZFY7KYrjvmPe+XY43ST8t1KaXQHViBHxL974y9MQrxycihpSnDBtmo0I9QXTGOCqGP H7kbCfbjiSbTZ4/y0HulrxH2AgBE6maO1efS/dvFJnhHmsyuaXufsw1Nyd8M0qndfh k6HS6NnyFSB24AzYa/WG5kSgVnXg05ZLHTmFrZctP4iDO7DJ8LJOWLAbxH52wyAfWm LrWfTOW9M8VBw== From: Masahiro Yamada To: linux-kbuild@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Nathan Chancellor , Nick Desaulniers , Nicolas Schier , Masahiro Yamada Subject: [PATCH v6 16/20] modpost: merge fromsec=DATA_SECTIONS entries in sectioncheck table Date: Mon, 22 May 2023 01:04:21 +0900 Message-Id: <20230521160426.1881124-17-masahiroy@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230521160426.1881124-1-masahiroy@kernel.org> References: <20230521160426.1881124-1-masahiroy@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org You can merge these entries. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- scripts/mod/modpost.c | 7 +------ 1 file changed, 1 insertion(+), 6 deletions(-) diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 516323c3910a..aea9d6cd243d 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -884,12 +884,7 @@ static const struct sectioncheck sectioncheck[] = { }, { .fromsec = { DATA_SECTIONS, NULL }, - .bad_tosec = { ALL_XXXINIT_SECTIONS, NULL }, - .mismatch = DATA_TO_ANY_INIT, -}, -{ - .fromsec = { DATA_SECTIONS, NULL }, - .bad_tosec = { INIT_SECTIONS, NULL }, + .bad_tosec = { ALL_XXXINIT_SECTIONS, INIT_SECTIONS, NULL }, .mismatch = DATA_TO_ANY_INIT, }, { From patchwork Sun May 21 16:04:22 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masahiro Yamada X-Patchwork-Id: 13249451 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 50F51C77B73 for ; Sun, 21 May 2023 16:07:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231159AbjEUQHU (ORCPT ); Sun, 21 May 2023 12:07:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56210 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231231AbjEUQHF (ORCPT ); Sun, 21 May 2023 12:07:05 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 00F6011F; Sun, 21 May 2023 09:06:38 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 9615561772; Sun, 21 May 2023 16:05:45 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B2B97C4339B; Sun, 21 May 2023 16:05:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1684685145; bh=Lm8ksZkkWnLti0mHUlCD6ajjZTqsYY5cMVf9EjewM9w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TdK53FM1qRG0L/Rn8FOqvnIfXjt/9/pqd/rYxzvd8FD45CBK1f+Lj2vjvHTu/t1r8 wyyp/1+J8c8OAv41ABbvkhQhWdXcSYSYDCyW9rO//gbwB0Bcqsx2Yn0Qxm9PhF/HVy q/0HI0rD1dD1d43tvXVOTV2Xbp6JvDLifm2actX3GQQC/S8GXhhnZU4P1mSEbCb7N7 zTo2ghmQ3qGMfMTyajqHl8k0fypLWc+IAB1GJvSVW29iWqr5vM3yyVPxIreuMezH7o AofzX+5UJFEL2mJQxvfMSoXIXVuKjtEAuCmcOy1EAT1r24j6yCKogvJcwNfS2iL4FN Zzj5leqHR7Z+A== From: Masahiro Yamada To: linux-kbuild@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Nathan Chancellor , Nick Desaulniers , Nicolas Schier , Masahiro Yamada Subject: [PATCH v6 17/20] modpost: merge bad_tosec=ALL_EXIT_SECTIONS entries in sectioncheck table Date: Mon, 22 May 2023 01:04:22 +0900 Message-Id: <20230521160426.1881124-18-masahiroy@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230521160426.1881124-1-masahiroy@kernel.org> References: <20230521160426.1881124-1-masahiroy@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org There is no distinction between TEXT_TO_ANY_EXIT and DATA_TO_ANY_EXIT. Just merge them. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- scripts/mod/modpost.c | 15 ++++----------- 1 file changed, 4 insertions(+), 11 deletions(-) diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index aea9d6cd243d..b5f7f4811c39 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -844,8 +844,7 @@ static const char *const optim_symbols[] = { "*.constprop.*", NULL }; enum mismatch { TEXT_TO_ANY_INIT, DATA_TO_ANY_INIT, - TEXT_TO_ANY_EXIT, - DATA_TO_ANY_EXIT, + TEXTDATA_TO_ANY_EXIT, XXXINIT_TO_SOME_INIT, XXXEXIT_TO_SOME_EXIT, ANY_INIT_TO_ANY_EXIT, @@ -888,14 +887,9 @@ static const struct sectioncheck sectioncheck[] = { .mismatch = DATA_TO_ANY_INIT, }, { - .fromsec = { TEXT_SECTIONS, NULL }, + .fromsec = { TEXT_SECTIONS, DATA_SECTIONS, NULL }, .bad_tosec = { ALL_EXIT_SECTIONS, NULL }, - .mismatch = TEXT_TO_ANY_EXIT, -}, -{ - .fromsec = { DATA_SECTIONS, NULL }, - .bad_tosec = { ALL_EXIT_SECTIONS, NULL }, - .mismatch = DATA_TO_ANY_EXIT, + .mismatch = TEXTDATA_TO_ANY_EXIT, }, /* Do not reference init code/data from meminit code/data */ { @@ -1162,8 +1156,7 @@ static void default_mismatch_handler(const char *modname, struct elf_info *elf, switch (mismatch->mismatch) { case TEXT_TO_ANY_INIT: case DATA_TO_ANY_INIT: - case TEXT_TO_ANY_EXIT: - case DATA_TO_ANY_EXIT: + case TEXTDATA_TO_ANY_EXIT: case XXXINIT_TO_SOME_INIT: case XXXEXIT_TO_SOME_EXIT: case ANY_INIT_TO_ANY_EXIT: From patchwork Sun May 21 16:04:23 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masahiro Yamada X-Patchwork-Id: 13249448 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F384DC77B73 for ; Sun, 21 May 2023 16:06:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231175AbjEUQGi (ORCPT ); Sun, 21 May 2023 12:06:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56186 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231173AbjEUQGS (ORCPT ); Sun, 21 May 2023 12:06:18 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 53BDF124; Sun, 21 May 2023 09:05:47 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 2E52460FB0; Sun, 21 May 2023 16:05:47 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 699FAC433D2; Sun, 21 May 2023 16:05:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1684685146; bh=xkkHzfnL3ubXNCXhol2tJvXMJSRLG0VEcBb56VUY1PA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=EVgHH4vJtM2RM6heu4Np31j75OuIt6w1WnPM3+OgbM1iI6dOK0EfPNRbPgKMZm8O4 GCa3kGdPYcvS5eN70GFAgbIc9A6LmVNAmJZzH6Qh253361qyDNp3ik1XQxksXGAPzo 3AsvNW+lrkx0fO7KDFp6y1U5AgYzjc2k35N94XXzMZFe54H8dDzi+Srei1IplPWpKU GIn7uOo9EEYo4xS830Tfh2fh7AJB5s3V7huCYuvoi81ufvdD/tINYf55fB47MWnovY VxprJvKl67DEizW/gbCfj0Y2+GX1fXy7PxQ3RZ1IFwupxCY4aOrkofNBnl1BwKmF3u J2xV5zqMcPqwA== From: Masahiro Yamada To: linux-kbuild@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Nathan Chancellor , Nick Desaulniers , Nicolas Schier , Masahiro Yamada Subject: [PATCH v6 18/20] modpost: remove *_sections[] arrays Date: Mon, 22 May 2023 01:04:23 +0900 Message-Id: <20230521160426.1881124-19-masahiroy@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230521160426.1881124-1-masahiroy@kernel.org> References: <20230521160426.1881124-1-masahiroy@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org Use PATTERNS() macros to remove unneeded array definitions. Signed-off-by: Masahiro Yamada --- scripts/mod/modpost.c | 36 +++++++++--------------------------- 1 file changed, 9 insertions(+), 27 deletions(-) diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index b5f7f4811c39..852cc164c77e 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -823,24 +823,6 @@ static void check_section(const char *modname, struct elf_info *elf, #define ALL_TEXT_SECTIONS ALL_INIT_TEXT_SECTIONS, ALL_EXIT_TEXT_SECTIONS, \ TEXT_SECTIONS, OTHER_TEXT_SECTIONS -/* init data sections */ -static const char *const init_data_sections[] = - { ALL_INIT_DATA_SECTIONS, NULL }; - -/* all init sections */ -static const char *const init_sections[] = { ALL_INIT_SECTIONS, NULL }; - -/* all text sections */ -static const char *const text_sections[] = { ALL_TEXT_SECTIONS, NULL }; - -/* data section */ -static const char *const data_sections[] = { DATA_SECTIONS, NULL }; - -static const char *const head_sections[] = { ".head.text*", NULL }; -static const char *const linker_symbols[] = - { "__init_begin", "_sinittext", "_einittext", NULL }; -static const char *const optim_symbols[] = { "*.constprop.*", NULL }; - enum mismatch { TEXT_TO_ANY_INIT, DATA_TO_ANY_INIT, @@ -1006,14 +988,14 @@ static int secref_whitelist(const char *fromsec, const char *fromsym, const char *tosec, const char *tosym) { /* Check for pattern 1 */ - if (match(tosec, init_data_sections) && - match(fromsec, data_sections) && + if (match(tosec, PATTERNS(ALL_INIT_DATA_SECTIONS)) && + match(fromsec, PATTERNS(DATA_SECTIONS)) && strstarts(fromsym, "__param")) return 0; /* Check for pattern 1a */ if (strcmp(tosec, ".init.text") == 0 && - match(fromsec, data_sections) && + match(fromsec, PATTERNS(DATA_SECTIONS)) && strstarts(fromsym, "__param_ops_")) return 0; @@ -1036,18 +1018,18 @@ static int secref_whitelist(const char *fromsec, const char *fromsym, return 0; /* Check for pattern 3 */ - if (match(fromsec, head_sections) && - match(tosec, init_sections)) + if (strstarts(fromsec, ".head.text") && + match(tosec, PATTERNS(ALL_INIT_SECTIONS))) return 0; /* Check for pattern 4 */ - if (match(tosym, linker_symbols)) + if (match(tosym, PATTERNS("__init_begin", "_sinittext", "_einittext"))) return 0; /* Check for pattern 5 */ - if (match(fromsec, text_sections) && - match(tosec, init_sections) && - match(fromsym, optim_symbols)) + if (match(fromsec, PATTERNS(ALL_TEXT_SECTIONS)) && + match(tosec, PATTERNS(ALL_INIT_SECTIONS)) && + match(fromsym, PATTERNS("*.constprop.*"))) return 0; return 1; From patchwork Sun May 21 16:04:24 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masahiro Yamada X-Patchwork-Id: 13249447 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 64A00C7EE2A for ; Sun, 21 May 2023 16:06:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231166AbjEUQGi (ORCPT ); Sun, 21 May 2023 12:06:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56188 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231174AbjEUQGS (ORCPT ); Sun, 21 May 2023 12:06:18 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0DAB0E78; Sun, 21 May 2023 09:05:49 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id E23BC6179A; Sun, 21 May 2023 16:05:48 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1114CC4339E; Sun, 21 May 2023 16:05:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1684685148; bh=OsDQm9j1PsDhPRuAGeNz8Ube9RFsdeDF2EBPrRh3R00=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pSSCKgO/pgmJMYhG5PbEkacPkJY9fJzSjVvsy7mQ6g5XQ01mmRjzRWa0l5QGox1zj Ehse+zJR2r2fCka79ORaDKzj6yVqM5mxK7nXB4Kv/aOXj3iuPLmiBVlzi3wQnkvh/K gl7fj2T9p82yk3Ae/afrvt+jPkYL4dORCwGu1sQa6VhK6y2wsrh5ynhBLLselJ3+Hg jjvrrEfABBLm2CwQ3RWulT3jXzttTWAZ0621MtACF9jyf36m5f6j1yw+WT6t0JU0hl kFHtBhfwGzWb6VLUk9dRfAQCYUN+ISXdzTa2HcU74FcvIx0wsCB04D+sGcjAF+lh0S n+VHiBIAn+Y0w== From: Masahiro Yamada To: linux-kbuild@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Nathan Chancellor , Nick Desaulniers , Nicolas Schier , Masahiro Yamada Subject: [PATCH v6 19/20] modpost: merge two similar section mismatch warnings Date: Mon, 22 May 2023 01:04:24 +0900 Message-Id: <20230521160426.1881124-20-masahiroy@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230521160426.1881124-1-masahiroy@kernel.org> References: <20230521160426.1881124-1-masahiroy@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org In case of section mismatch, modpost shows slightly different messages. For extable section mismatch: "%s(%s+0x%lx): Section mismatch in reference to the %s:%s\n" For the other cases: "%s: section mismatch in reference: %s (section: %s) -> %s (section: %s)\n" They are similar. Merge them. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- scripts/mod/modpost.c | 18 +++--------------- 1 file changed, 3 insertions(+), 15 deletions(-) diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 852cc164c77e..e7561fa57478 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -1135,21 +1135,10 @@ static void default_mismatch_handler(const char *modname, struct elf_info *elf, sec_mismatch_count++; - switch (mismatch->mismatch) { - case TEXT_TO_ANY_INIT: - case DATA_TO_ANY_INIT: - case TEXTDATA_TO_ANY_EXIT: - case XXXINIT_TO_SOME_INIT: - case XXXEXIT_TO_SOME_EXIT: - case ANY_INIT_TO_ANY_EXIT: - case ANY_EXIT_TO_ANY_INIT: - warn("%s: section mismatch in reference: %s (section: %s) -> %s (section: %s)\n", - modname, fromsym, fromsec, tosym, tosec); - break; - case EXTABLE_TO_NON_TEXT: - warn("%s(%s+0x%lx): Section mismatch in reference to the %s:%s\n", - modname, fromsec, (long)faddr, tosec, tosym); + warn("%s: section mismatch in reference: %s (section: %s) -> %s (section: %s)\n", + modname, fromsym, fromsec, tosym, tosec); + if (mismatch->mismatch == EXTABLE_TO_NON_TEXT) { if (match(tosec, mismatch->bad_tosec)) fatal("The relocation at %s+0x%lx references\n" "section \"%s\" which is black-listed.\n" @@ -1169,7 +1158,6 @@ static void default_mismatch_handler(const char *modname, struct elf_info *elf, else error("%s+0x%lx references non-executable section '%s'\n", fromsec, (long)faddr, tosec); - break; } } From patchwork Sun May 21 16:04:25 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masahiro Yamada X-Patchwork-Id: 13249452 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E8B62C77B73 for ; Sun, 21 May 2023 16:07:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230340AbjEUQHa (ORCPT ); Sun, 21 May 2023 12:07:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57032 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230487AbjEUQHP (ORCPT ); Sun, 21 May 2023 12:07:15 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E1ACC10C9; Sun, 21 May 2023 09:06:50 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id E5DAB6150E; Sun, 21 May 2023 16:05:50 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C5F73C4339C; Sun, 21 May 2023 16:05:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1684685150; bh=yLNmLqnZjiVDJ1+11bIdJ/9gglrLgGpnva7MS4wZCMA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fuQmkKOb2ikon5r/q2qXFOV5oTZZS8XMuVYB/PsHRLP7PCSsjM0E+NeEa8UivuKmQ CnAxtt76X6Q5icdBf97JfxWVKmhiQro5JfTBzKP2CRasqalW6XLq3aR9SYOWg4cyX6 yrBimkCoAp3F31cJyfcQ+jW4ODLwBsH3e3VtpModseDbwsb5tjVLF2tZH6tk1v/b0q TqBVYxIe8uD5mbHSSv4cGsuFW1HaskwvAayHj8FTZPINe9MpmF30qq6HqhG04xuRUd pT58HZ9HRiqwxb5t/9a8cKQC4OHDk0uZRAhfja7MaFwYQyea7MhCcvO9/XTL78tzU7 p/ar05SiIS3tw== From: Masahiro Yamada To: linux-kbuild@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Nathan Chancellor , Nick Desaulniers , Nicolas Schier , Masahiro Yamada Subject: [PATCH v6 20/20] modpost: show offset from symbol for section mismatch warnings Date: Mon, 22 May 2023 01:04:25 +0900 Message-Id: <20230521160426.1881124-21-masahiroy@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230521160426.1881124-1-masahiroy@kernel.org> References: <20230521160426.1881124-1-masahiroy@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org Currently, modpost only shows the symbol names and section names, so it repeats the same message if there are multiple relocations in the same symbol. It is common the relocation spans across multiple instructions. It is better to show the offset from the symbol. Signed-off-by: Masahiro Yamada --- scripts/mod/modpost.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index e7561fa57478..4da96746a03b 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -1135,8 +1135,8 @@ static void default_mismatch_handler(const char *modname, struct elf_info *elf, sec_mismatch_count++; - warn("%s: section mismatch in reference: %s (section: %s) -> %s (section: %s)\n", - modname, fromsym, fromsec, tosym, tosec); + warn("%s: section mismatch in reference: %s+0x%x (section: %s) -> %s (section: %s)\n", + modname, fromsym, (unsigned int)(faddr - from->st_value), fromsec, tosym, tosec); if (mismatch->mismatch == EXTABLE_TO_NON_TEXT) { if (match(tosec, mismatch->bad_tosec))