From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out203-205-221-209.mail.qq.com (out203-205-221-209.mail.qq.com [203.205.221.209]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C84163EA96; Sat, 27 Apr 2024 05:28:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=203.205.221.209 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714195719; cv=none; b=Bz0m0zIWc9Ll5HvXF25pIB2PNEvZYy7Uu0uuufNVEYsiswljeDb6N2mxhxMXcMHqHo3IByuWq9WrLzka8IliVqMVjh5Q+6+LYkD/FQpsdXhGV1cSOFzJRhcTXqosgGnCNSPKvqbSu0PBJ32sQueoU9kfYBg+odoy0VVSFdyl9+o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714195719; c=relaxed/simple; bh=GwqpKC5+LkRLRTZ4RlLT13C4t8nOGVEKrN3Cl/Yjgm8=; h=Message-ID:From:To:Cc:Subject:Date:MIME-Version; b=FJZMuL7oySwVzVK6WaAr2gUwd+tAMVYJ7mJvcsw13s8WTE/kkEPxxgOrGjSYSv2tb8hsS/VkLRQmfYbefRBSreRBEzs/RPotkUN6bJoGLdUZ3zb2EbBZGh4Wimcv8RKNs05UqbWDRHx0rqu7TDFEamt9ZxKYenQX4nFvfkLRCs0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=qq.com; spf=pass smtp.mailfrom=qq.com; dkim=pass (1024-bit key) header.d=qq.com header.i=@qq.com header.b=tIwLi7UW; arc=none smtp.client-ip=203.205.221.209 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=qq.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=qq.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=qq.com header.i=@qq.com header.b="tIwLi7UW" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=qq.com; s=s201512; t=1714195704; bh=OPRLB2fvbwGnGWhWWCaQT4aiVsrtxUso4PGORBObRx0=; h=From:To:Cc:Subject:Date; b=tIwLi7UWenf68TtvO8RZqWj61IASgk3P7bsMXQXAq358VYQkQFI/rHNvii0zFerBb JWNFn/V4U8EiXSQD2jK8kbGxTHWVTqaZiqAHI7TBhtLUsSumTgZjCNPqXVr08VM4jb hO9vP/gY0YZVdtZUlF7x9lyjFQGOWbjRmCzz3OFo= Received: from localhost.localdomain ([58.213.8.145]) by newxmesmtplogicsvrsza29-0.qq.com (NewEsmtp) with SMTP id 649974F2; Sat, 27 Apr 2024 13:25:09 +0800 X-QQ-mid: xmsmtpt1714195509tnziqak7s Message-ID: X-QQ-XMAILINFO: NMGzQWUSIfvTorIFbPMI2XNbz0tgf4ZkeLxSeVT6T+LxYTX4HeP/Fm/R64o4ie AHoK3qD2FK+DKjsvGmtc+XmK11Spn/YvDtY6lfrkYBu7KeQV+EE9WUYg2kZw/MmCUUmOgbUZ9/O7 Rl2U/CsEjoCJEtucuikX4OB6L/IuNiMLtgRU9Fk8CGLrsIvuoQdCM106qVneT/claNqKvQSwXNNc v32sGYOYrD/nvoQGjEwRnNEWt+EINwK/k66fwaKOer+d1Shaa5ZJ/H/Bbb0mEaEpFClgEDDa6vm8 z985LRVxZ+VABus2/qju9LDVLSSP3hq9LnmlIunv/eb1b8LGlAr5wCwi7N8OQI/kXEtQu3AfyGvu ChDM5ObRRg7zy7Q+EnIxzekMG52emLLPpRuOx1X8EO184yvbVYXj5fCzACX8LygFSeUzAaoKigR7 YM/R5ZGWGBjIZzYELrbI2FOGSOUzEbkBwc0VQjCL4T6D56oXnfnHLduHq//61mTRGiqohvQprUN9 uvPEKEYCoEKPCu4ta2b/FHxV3qWniB2ZqA6fsh4IRB5UutDA1++KSoclqH231puFFPLbmEn9ExLu zkqXoP5mFZH77QGTKbG7lz553opN5G1uSS0aGlmyj8TVnf/HdMR3IpKP8c3EGuaJnUHpjGQX6/iF JUGyo1ZfK5yp5giGICR7EHP5WV+CNoFtA6nNh079ZwTDk1nnrLO/1+uztbIr5A4XRXB0hwE+2h+c 1rTIBoBOBBYknpXLBKOU1RGivBFq9DPuIplSTmmKLA9lAS/u2HYEKzzg8XfwBYQ5qVntoriRnJ7R rQTV50uV6/DUE6CsOaPL7wtbpr5yXphZe/91Hw5rbqT+dnc4rQ77fiwi8opFbyDbWiISWuY0IFvG 0gSHfiseMf8iP9eEkSB6+DbPNjNK/XiKaUNyOiib5hUqaMISqdUM0LW/tvZYumhGQZYW9oH8koqk qscSm7RWamV+rxXuNRFYHUS7U8YQToE8nOdXlCx7cZ/vo8VttRGnsVegynYj2ildEsY/P1ims= X-QQ-XMRINFO: OWPUhxQsoeAVDbp3OJHYyFg= From: linke li To: Cc: xujianhao01@gmail.com, linke li , Ard Biesheuvel , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] x86/efi: mark racy access on efi_rts_work.efi_rts_id Date: Sat, 27 Apr 2024 13:25:07 +0800 X-OQ-MSGID: <20240427052507.29801-1-lilinke99@qq.com> X-Mailer: git-send-email 2.39.3 (Apple Git-146) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit In efi_crash_gracefully_on_page_fault(), efi_rts_work.efi_rts_id can by changed by other thread from the comment. Mark possible data race on efi_rts_work.efi_rts_id as benign using READ_ONCE. This patch is aimed at reducing the number of benign races reported by KCSAN in order to focus future debugging effort on harmful races. Signed-off-by: linke li --- arch/x86/platform/efi/quirks.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/platform/efi/quirks.c b/arch/x86/platform/efi/quirks.c index f0cc00032751..4acb81700caf 100644 --- a/arch/x86/platform/efi/quirks.c +++ b/arch/x86/platform/efi/quirks.c @@ -751,7 +751,7 @@ void efi_crash_gracefully_on_page_fault(unsigned long phys_addr) * because this case occurs *very* rarely and hence could be improved * on a need by basis. */ - if (efi_rts_work.efi_rts_id == EFI_RESET_SYSTEM) { + if (READ_ONCE(efi_rts_work.efi_rts_id) == EFI_RESET_SYSTEM) { pr_info("efi_reset_system() buggy! Reboot through BIOS\n"); machine_real_restart(MRR_BIOS); return; -- 2.39.3 (Apple Git-146)