From patchwork Sun Dec 4 17:46:29 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jisheng Zhang X-Patchwork-Id: 13063944 X-Patchwork-Delegate: palmer@dabbelt.com 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 5C27EC4321E for ; Sun, 4 Dec 2022 18:00:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=p6YbcvuinkKjB/h7sBM5FelLmSn3tALYbbK0xrxc88g=; b=cNWkAtNyMSDxKO gmXSA8Em1OYmXhUskIomsGaeIzYzcoktai6H8Xg1HQK1doXCiwOdVBe+XXAAT6EVXvh7ioNo+tgBm Vz3r4jzqMlP7GaX3LBWjSPgS4G00PZnfYrXVbQ491L/yHl/E/tocm6H0rQz2hjZi+a4vdJhomsnZB p4/bgbnwxwL2CxnOYoawc3Sr1qhENezWCS5xaWKspsxxHoH1leoAWEfoOHk0mWoupThJbkkhlsjIF h3F/z1v6TWfEjKP8QknmVRyWEq7soKg9swtUSLHGn2uoJ9cvBLMXwDFahSQvtqpe3aGxcwz1wCmjl WbrvK31x4Uf9wJM2z+CQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1p1tHx-00A7nq-1E; Sun, 04 Dec 2022 18:00:29 +0000 Received: from ams.source.kernel.org ([145.40.68.75]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1p1tEZ-00A6hn-BR; Sun, 04 Dec 2022 17:57:00 +0000 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 ams.source.kernel.org (Postfix) with ESMTPS id C80D1B80A3A; Sun, 4 Dec 2022 17:56:57 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 33507C433C1; Sun, 4 Dec 2022 17:56:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1670176616; bh=nddkFzTLXcp78CwhK+bTE7WNJIO4yesPGtU3kIxPL38=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=UXAqMPoX0wN90WTipazw5XiEoicdzJeJI0ye3r5zOGvgziDQrMj63YWPVJ9oAOqnl mF09A3ujxVYGFzgmLc4P1X5u97N9NISDjG9YJ4hCSYyeEePdOwD77nkwsTxeSp+Wg1 97KtA6tZYvuF1040OMH1mOQoDuVnjigVVN3Yn9odB/fSA3WqfN/nlBHBbSW3+D6vkp bkWYoUXx8uUtnST1LTpA5kRL2QKniEtn748UIpoOj56m/7QRthbezm7jjUwcB5G1lt ho4a9QtlLQZLX5C041vZVUgzMWBTJbUTEvR1kxWwwiFceWhrGBEJ5soA4jXAtG+EAC 1yDT5eTiwRtdQ== From: Jisheng Zhang To: Palmer Dabbelt , Paul Walmsley , Albert Ou , Anup Patel , Atish Patra , Heiko Stuebner , Andrew Jones Cc: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, kvm-riscv@lists.infradead.org Subject: [PATCH v2 10/13] riscv: alternative: patch alternatives in the vDSO Date: Mon, 5 Dec 2022 01:46:29 +0800 Message-Id: <20221204174632.3677-11-jszhang@kernel.org> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20221204174632.3677-1-jszhang@kernel.org> References: <20221204174632.3677-1-jszhang@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221204_095659_692020_1DFA2472 X-CRM114-Status: GOOD ( 14.68 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org Make it possible to use alternatives in the vDSO, so that better implementations can be used if possible. Signed-off-by: Jisheng Zhang Reviewed-by: Guo Ren Reviewed-by: Andrew Jones --- arch/riscv/include/asm/vdso.h | 4 ++++ arch/riscv/kernel/alternative.c | 25 +++++++++++++++++++++++++ arch/riscv/kernel/vdso.c | 5 ----- arch/riscv/kernel/vdso/vdso.lds.S | 7 +++++++ 4 files changed, 36 insertions(+), 5 deletions(-) diff --git a/arch/riscv/include/asm/vdso.h b/arch/riscv/include/asm/vdso.h index af981426fe0f..b6ff7473fb8a 100644 --- a/arch/riscv/include/asm/vdso.h +++ b/arch/riscv/include/asm/vdso.h @@ -28,8 +28,12 @@ #define COMPAT_VDSO_SYMBOL(base, name) \ (void __user *)((unsigned long)(base) + compat__vdso_##name##_offset) +extern char compat_vdso_start[], compat_vdso_end[]; + #endif /* CONFIG_COMPAT */ +extern char vdso_start[], vdso_end[]; + #endif /* !__ASSEMBLY__ */ #endif /* CONFIG_MMU */ diff --git a/arch/riscv/kernel/alternative.c b/arch/riscv/kernel/alternative.c index 9d88375624b5..eaf7ddaba54c 100644 --- a/arch/riscv/kernel/alternative.c +++ b/arch/riscv/kernel/alternative.c @@ -11,7 +11,9 @@ #include #include #include +#include #include +#include #include #include #include @@ -187,6 +189,27 @@ static void __init_or_module _apply_alternatives(struct alt_entry *begin, stage); } +static void __init apply_vdso_alternatives(void) +{ + const struct elf64_hdr *hdr; + const struct elf64_shdr *shdr; + const struct elf64_shdr *alt; + struct alt_entry *begin, *end; + + hdr = (struct elf64_hdr *)vdso_start; + shdr = (void *)hdr + hdr->e_shoff; + alt = find_section(hdr, shdr, ".alternative"); + if (!alt) + return; + + begin = (void *)hdr + alt->sh_offset, + end = (void *)hdr + alt->sh_offset + alt->sh_size, + + _apply_alternatives((struct alt_entry *)begin, + (struct alt_entry *)end, + RISCV_ALTERNATIVES_BOOT); +} + void __init apply_boot_alternatives(void) { /* If called on non-boot cpu things could go wrong */ @@ -195,6 +218,8 @@ void __init apply_boot_alternatives(void) _apply_alternatives((struct alt_entry *)__alt_start, (struct alt_entry *)__alt_end, RISCV_ALTERNATIVES_BOOT); + + apply_vdso_alternatives(); } /* diff --git a/arch/riscv/kernel/vdso.c b/arch/riscv/kernel/vdso.c index 123d05255fcf..1f47bc6566cf 100644 --- a/arch/riscv/kernel/vdso.c +++ b/arch/riscv/kernel/vdso.c @@ -22,11 +22,6 @@ struct vdso_data { }; #endif -extern char vdso_start[], vdso_end[]; -#ifdef CONFIG_COMPAT -extern char compat_vdso_start[], compat_vdso_end[]; -#endif - enum vvar_pages { VVAR_DATA_PAGE_OFFSET, VVAR_TIMENS_PAGE_OFFSET, diff --git a/arch/riscv/kernel/vdso/vdso.lds.S b/arch/riscv/kernel/vdso/vdso.lds.S index 150b1a572e61..4a0606633290 100644 --- a/arch/riscv/kernel/vdso/vdso.lds.S +++ b/arch/riscv/kernel/vdso/vdso.lds.S @@ -40,6 +40,13 @@ SECTIONS . = 0x800; .text : { *(.text .text.*) } :text + . = ALIGN(4); + .alternative : { + __alt_start = .; + *(.alternative) + __alt_end = .; + } + .data : { *(.got.plt) *(.got) *(.data .data.* .gnu.linkonce.d.*)