From patchwork Fri Apr 9 20:27:26 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 12195027 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 07108C43470 for ; Fri, 9 Apr 2021 20:27:29 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id A549E61181 for ; Fri, 9 Apr 2021 20:27:28 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A549E61181 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 49A046B007B; Fri, 9 Apr 2021 16:27:28 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 471076B007D; Fri, 9 Apr 2021 16:27:28 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 338E06B007E; Fri, 9 Apr 2021 16:27:28 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0204.hostedemail.com [216.40.44.204]) by kanga.kvack.org (Postfix) with ESMTP id 14EBF6B007B for ; Fri, 9 Apr 2021 16:27:28 -0400 (EDT) Received: from smtpin38.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id CCD35B9FE for ; Fri, 9 Apr 2021 20:27:27 +0000 (UTC) X-FDA: 78013963734.38.AFBE5D2 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf17.hostedemail.com (Postfix) with ESMTP id 90EE140002D0 for ; Fri, 9 Apr 2021 20:27:25 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 6F2A86113A; Fri, 9 Apr 2021 20:27:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1618000046; bh=MC5rJIiACHa4l6pT6GTWaov4H6yXZ+j3/ppxa3BO3ts=; h=Date:From:To:Subject:In-Reply-To:From; b=YbZ2Y0PhHjNGMsgKJT+4ep/68sV/XRY+Q1U8Afv6NBLkO7LAZEr3SRzyiSNVE9M/u KdmXO4N6aEER1uTe3WrKBsg6kkbqsV+fQUoRfweRT2WtytxHzo+Dc9dU1yl8EUQSuH Cdl4hj4hgV/mpozo2iqbJ1W68uNk9WpZpsMxVm0A= Date: Fri, 09 Apr 2021 13:27:26 -0700 From: Andrew Morton To: akpm@linux-foundation.org, linux-mm@kvack.org, mm-commits@vger.kernel.org, nathan@kernel.org, ndesaulniers@google.com, psodagud@quicinc.com, stable@vger.kernel.org, torvalds@linux-foundation.org Subject: [patch 09/16] gcov: re-fix clang-11+ support Message-ID: <20210409202726.UGh0KJFgU%akpm@linux-foundation.org> In-Reply-To: <20210409132633.6855fc8fea1b3905ea1bb4be@linux-foundation.org> User-Agent: s-nail v14.8.16 X-Stat-Signature: ykqqim8fuc4fr8yyp7g8m4sgdo9dek7k X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 90EE140002D0 Received-SPF: none (linux-foundation.org>: No applicable sender policy available) receiver=imf17; identity=mailfrom; envelope-from=""; helo=mail.kernel.org; client-ip=198.145.29.99 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1618000045-125031 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Nick Desaulniers Subject: gcov: re-fix clang-11+ support LLVM changed the expected function signature for llvm_gcda_emit_function() in the clang-11 release. Users of clang-11 or newer may have noticed their kernels producing invalid coverage information: $ llvm-cov gcov -a -c -u -f -b .gcda -- gcno=.gcno 1 : checksum mismatch, \ (, ) != (, ) 2 Invalid .gcda File! ... Fix up the function signatures so calling this function interprets its parameters correctly and computes the correct cfg checksum. In particular, in clang-11, the additional checksum is no longer optional. Link: https://reviews.llvm.org/rG25544ce2df0daa4304c07e64b9c8b0f7df60c11d Link: https://lkml.kernel.org/r/20210408184631.1156669-1-ndesaulniers@google.com Reported-by: Prasad Sodagudi Tested-by: Prasad Sodagudi Signed-off-by: Nick Desaulniers Reviewed-by: Nathan Chancellor Cc: [5.4+] Signed-off-by: Andrew Morton --- kernel/gcov/clang.c | 29 +++++++++++++++++++---------- 1 file changed, 19 insertions(+), 10 deletions(-) --- a/kernel/gcov/clang.c~gcov-re-fix-clang-11-support +++ a/kernel/gcov/clang.c @@ -70,7 +70,9 @@ struct gcov_fn_info { u32 ident; u32 checksum; +#if CONFIG_CLANG_VERSION < 110000 u8 use_extra_checksum; +#endif u32 cfg_checksum; u32 num_counters; @@ -145,10 +147,8 @@ void llvm_gcda_emit_function(u32 ident, list_add_tail(&info->head, ¤t_info->functions); } -EXPORT_SYMBOL(llvm_gcda_emit_function); #else -void llvm_gcda_emit_function(u32 ident, u32 func_checksum, - u8 use_extra_checksum, u32 cfg_checksum) +void llvm_gcda_emit_function(u32 ident, u32 func_checksum, u32 cfg_checksum) { struct gcov_fn_info *info = kzalloc(sizeof(*info), GFP_KERNEL); @@ -158,12 +158,11 @@ void llvm_gcda_emit_function(u32 ident, INIT_LIST_HEAD(&info->head); info->ident = ident; info->checksum = func_checksum; - info->use_extra_checksum = use_extra_checksum; info->cfg_checksum = cfg_checksum; list_add_tail(&info->head, ¤t_info->functions); } -EXPORT_SYMBOL(llvm_gcda_emit_function); #endif +EXPORT_SYMBOL(llvm_gcda_emit_function); void llvm_gcda_emit_arcs(u32 num_counters, u64 *counters) { @@ -293,11 +292,16 @@ int gcov_info_is_compatible(struct gcov_ !list_is_last(&fn_ptr2->head, &info2->functions)) { if (fn_ptr1->checksum != fn_ptr2->checksum) return false; +#if CONFIG_CLANG_VERSION < 110000 if (fn_ptr1->use_extra_checksum != fn_ptr2->use_extra_checksum) return false; if (fn_ptr1->use_extra_checksum && fn_ptr1->cfg_checksum != fn_ptr2->cfg_checksum) return false; +#else + if (fn_ptr1->cfg_checksum != fn_ptr2->cfg_checksum) + return false; +#endif fn_ptr1 = list_next_entry(fn_ptr1, head); fn_ptr2 = list_next_entry(fn_ptr2, head); } @@ -529,17 +533,22 @@ static size_t convert_to_gcda(char *buff list_for_each_entry(fi_ptr, &info->functions, head) { u32 i; - u32 len = 2; - - if (fi_ptr->use_extra_checksum) - len++; pos += store_gcov_u32(buffer, pos, GCOV_TAG_FUNCTION); - pos += store_gcov_u32(buffer, pos, len); +#if CONFIG_CLANG_VERSION < 110000 + pos += store_gcov_u32(buffer, pos, + fi_ptr->use_extra_checksum ? 3 : 2); +#else + pos += store_gcov_u32(buffer, pos, 3); +#endif pos += store_gcov_u32(buffer, pos, fi_ptr->ident); pos += store_gcov_u32(buffer, pos, fi_ptr->checksum); +#if CONFIG_CLANG_VERSION < 110000 if (fi_ptr->use_extra_checksum) pos += store_gcov_u32(buffer, pos, fi_ptr->cfg_checksum); +#else + pos += store_gcov_u32(buffer, pos, fi_ptr->cfg_checksum); +#endif pos += store_gcov_u32(buffer, pos, GCOV_TAG_COUNTER_BASE); pos += store_gcov_u32(buffer, pos, fi_ptr->num_counters * 2);