From mboxrd@z Thu Jan 1 00:00:00 1970 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=-19.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, 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,USER_AGENT_GIT autolearn=ham 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 306FDC433EC for ; Wed, 24 Mar 2021 02:05:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 059CF61A49 for ; Wed, 24 Mar 2021 02:05:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234808AbhCXCFS (ORCPT ); Tue, 23 Mar 2021 22:05:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58202 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234736AbhCXCFB (ORCPT ); Tue, 23 Mar 2021 22:05:01 -0400 Received: from mail-pj1-x1031.google.com (mail-pj1-x1031.google.com [IPv6:2607:f8b0:4864:20::1031]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6836AC061763 for ; Tue, 23 Mar 2021 19:04:50 -0700 (PDT) Received: by mail-pj1-x1031.google.com with SMTP id t18so10907949pjs.3 for ; Tue, 23 Mar 2021 19:04:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=eWsj2DeYWnLc9/yzhhDbW3exI1i+s3CCqepcW30l9Lc=; b=MydlPqdxPD/RZXfJGvGivV590W54/wXYFSVVKfQ4Zua9apxErbRo+qQ+GEKOEn6iPS IfCpFtjdKPuI2DdvFpj+IBTmag/xJnZjtmzqyhLOTjf0dRTUsWYHXzVSEorR8zy0wliy 8b90K9p/IG0Y5N1XewofVX5QvPaxdeTVpkbXw= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=eWsj2DeYWnLc9/yzhhDbW3exI1i+s3CCqepcW30l9Lc=; b=Sswq4/tQBZB0FZK/DImu+/pJH289EYLcsCniWk/LtlzR+7wCOBOq4aILiO2bM0By+P cdU1hH9yzxkoeZTHLU3qKFBPuIDTG+J7qwH5CR7PcQ1DzXgDNlAjX0m1xZ/uITkQmd6t ULo0rsKXOpI4b5KSJUrT2btsdh2+ZbDqc/rTGw5AYIjvmNezCVQCElfwPKlyn22CR4Ze MALKZDZCQKDxutsW4381YiY8GmmoWhDH+a6ZId5s/3evCkBorCZjiJsKGRw9c0ShV74w i2cTbX16slkeSMhgp1fPu40WbCfh5prx4BtSpZDeNGDPSPsGWK9kkTWUrKrUJrrrIH38 zwWA== X-Gm-Message-State: AOAM531LJeLp8lqvlo/fTgAQ5SkvbGaQ9qkvIREAvLvHLgXVHwgCZM+C vCuavLBlRc29K2yV1yP8n//MMj3Xp4mi8w== X-Google-Smtp-Source: ABdhPJwQUYj+45m7nIwY+1Mq5EuK8+aJBVx6aojuHt2uebSXGTgGoQuwt6m7tgpqZU+wQSmouFaGGw== X-Received: by 2002:a17:90a:f0c9:: with SMTP id fa9mr951129pjb.39.1616551489955; Tue, 23 Mar 2021 19:04:49 -0700 (PDT) Received: from smtp.gmail.com ([2620:15c:202:201:84ac:62f7:16a8:ccc7]) by smtp.gmail.com with ESMTPSA id b3sm389441pjg.41.2021.03.23.19.04.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 23 Mar 2021 19:04:49 -0700 (PDT) From: Stephen Boyd To: Andrew Morton Cc: linux-kernel@vger.kernel.org, Jiri Olsa , Alexei Starovoitov , Jessica Yu , Evan Green , Hsin-Yi Wang , Petr Mladek , Steven Rostedt , Andy Shevchenko , Matthew Wilcox Subject: [PATCH v2 03/12] dump_stack: Add vmlinux build ID to stack traces Date: Tue, 23 Mar 2021 19:04:34 -0700 Message-Id: <20210324020443.1815557-4-swboyd@chromium.org> X-Mailer: git-send-email 2.31.0.291.g576ba9dcdaf-goog In-Reply-To: <20210324020443.1815557-1-swboyd@chromium.org> References: <20210324020443.1815557-1-swboyd@chromium.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add the running kernel's build ID[1] to the stacktrace information header. This makes it simpler for developers to locate the vmlinux with full debuginfo for a particular kernel stacktrace. Combined with scripts/decode_stracktrace.sh, a developer can download the correct vmlinux from a debuginfod[2] server and find the exact file and line number for the functions plus offsets in a stacktrace. This is especially useful for pstore crash debugging where the kernel crashes are recorded in the pstore logs and the recovery kernel is different or the debuginfo doesn't exist on the device due to space concerns (the data can be large and a security concern). The stacktrace can be analyzed after the crash by using the build ID to find the matching vmlinux and understand where in the function something went wrong. Example stacktrace from lkdtm: WARNING: CPU: 4 PID: 3255 at drivers/misc/lkdtm/bugs.c:83 lkdtm_WARNING+0x28/0x30 [lkdtm] Modules linked in: lkdtm rfcomm algif_hash algif_skcipher af_alg xt_cgroup uinput xt_MASQUERADE CPU: 4 PID: 3255 Comm: bash Not tainted 5.11 #3 aa23f7a1231c229de205662d5a9e0d4c580f19a1 Hardware name: Google Lazor (rev3+) with KB Backlight (DT) pstate: 00400009 (nzcv daif +PAN -UAO -TCO BTYPE=--) pc : lkdtm_WARNING+0x28/0x30 [lkdtm] lr : lkdtm_do_action+0x24/0x40 [lkdtm] sp : ffffffc0134fbca0 x29: ffffffc0134fbca0 x28: ffffff92d53ba240 x27: 0000000000000000 x26: 0000000000000000 x25: 0000000000000000 x24: ffffffe3622352c0 x23: 0000000000000020 x22: ffffffe362233366 x21: ffffffe3622352e0 x20: ffffffc0134fbde0 x19: 0000000000000008 x18: 0000000000000000 x17: ffffff929b6536fc x16: 0000000000000000 x15: 0000000000000000 x14: 0000000000000012 x13: ffffffe380ed892c x12: ffffffe381d05068 x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000001 x8 : ffffffe362237000 x7 : aaaaaaaaaaaaaaaa x6 : 0000000000000000 x5 : 0000000000000000 x4 : 0000000000000001 x3 : 0000000000000008 x2 : ffffff93fef25a70 x1 : ffffff93fef15788 x0 : ffffffe3622352e0 Call trace: lkdtm_WARNING+0x28/0x30 [lkdtm] direct_entry+0x16c/0x1b4 [lkdtm] full_proxy_write+0x74/0xa4 vfs_write+0xec/0x2e8 ksys_write+0x84/0xf0 __arm64_sys_write+0x24/0x30 el0_svc_common+0xf4/0x1c0 do_el0_svc_compat+0x28/0x3c el0_svc_compat+0x10/0x1c el0_sync_compat_handler+0xa8/0xcc el0_sync_compat+0x178/0x180 ---[ end trace 3d95032303e59e68 ]--- The hex string aa23f7a1231c229de205662d5a9e0d4c580f19a1 is the build ID, following the kernel version number. Cc: Jiri Olsa Cc: Alexei Starovoitov Cc: Jessica Yu Cc: Evan Green Cc: Hsin-Yi Wang Cc: Petr Mladek Cc: Steven Rostedt Cc: Andy Shevchenko Cc: Matthew Wilcox Link: https://fedoraproject.org/wiki/Releases/FeatureBuildId [1] Link: https://sourceware.org/elfutils/Debuginfod.html [2] Signed-off-by: Stephen Boyd --- lib/dump_stack.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/lib/dump_stack.c b/lib/dump_stack.c index f5a33b6f773f..136bb942c4a3 100644 --- a/lib/dump_stack.c +++ b/lib/dump_stack.c @@ -5,6 +5,7 @@ */ #include +#include #include #include #include @@ -45,13 +46,13 @@ void __init dump_stack_set_arch_desc(const char *fmt, ...) */ void dump_stack_print_info(const char *log_lvl) { - printk("%sCPU: %d PID: %d Comm: %.20s %s%s %s %.*s\n", + printk("%sCPU: %d PID: %d Comm: %.20s %s%s %s %.*s %20phN\n", log_lvl, raw_smp_processor_id(), current->pid, current->comm, kexec_crash_loaded() ? "Kdump: loaded " : "", print_tainted(), init_utsname()->release, (int)strcspn(init_utsname()->version, " "), - init_utsname()->version); + init_utsname()->version, vmlinux_build_id()); if (dump_stack_arch_desc_str[0] != '\0') printk("%sHardware name: %s\n", -- https://chromeos.dev