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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 67DC7C433FE for ; Fri, 22 Oct 2021 07:43:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4FBE1610E7 for ; Fri, 22 Oct 2021 07:43:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232154AbhJVHqN (ORCPT ); Fri, 22 Oct 2021 03:46:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47346 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231773AbhJVHqL (ORCPT ); Fri, 22 Oct 2021 03:46:11 -0400 Received: from mail-wr1-x433.google.com (mail-wr1-x433.google.com [IPv6:2a00:1450:4864:20::433]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 20D8CC061764; Fri, 22 Oct 2021 00:43:54 -0700 (PDT) Received: by mail-wr1-x433.google.com with SMTP id d3so3333249wrh.8; Fri, 22 Oct 2021 00:43:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=QDe8eGn1242gSfR7Is43fRQHdJR93magL2F5GakfHEE=; b=mjxadADG3/7KVemwPXS50oEIEXflR9aiQ/P8tEKIYGuxFixdw96R+9yMdN7mPVO1GS eFT2suEIg9Y592iMRV9s40AfwLs2ncJ1aN5UEtbz9WPmR59kzaECpfBS77Anku1YNu3/ AQC8fl6BZHD6O0CQyj6GvwiVBMLGb4OO9EVt2Et5BkLUGpk8wqt8gZUF6OjIaLIJTaTU nL0xiVJgGDKJSGeV6xE5esknbaeq9h6hzoDkP3HnbZTpsyd5dx385PLuqGLirnWTB+zN beKDI+MwOBzxNfNJAz5Mb25SN7FSnh0ZLliQ+/H1BKqcD8QUFg+qXThCYX2VsydXZkqg uwaA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to; bh=QDe8eGn1242gSfR7Is43fRQHdJR93magL2F5GakfHEE=; b=3CGRRlKrg8Q+1kz+DTWLzWoNxEjAZdld4YNj51g7EYATagKD4Rix27g8CJfUY4hdn4 WQumMdzZlAsvAEGrZClXZ8tONot2d7S1mBqCLPWYjq/eEPOGgeGppZ1xomJTQu3TNH5a D4mDe00bigOjCesTflxNgi9/eE0BhVWxfP4F6Anoph1uV2C1bHa+QnEZgDiOLbBhiMna WExu9Gvcfggf19DfJd6O3AcgNhJ6XTQ/J9ayJLlyGgz5Rf3TyjkDTa8/Gp1VBJS5tK3c 6lO/4Gj3DLguwbtQKDMS5B9pxNM3ECmAkysyIWy0Ibw62SkJryak5tBn+5lc/kIaoAtb O08w== X-Gm-Message-State: AOAM533QEP3CgH/QDE9Q2ZUCp3JXzh+j5gRa3ad1qUYQBuYX7yUP7Hce CbSzm02MsMrp4E4/4POe1s+F30GdWDc= X-Google-Smtp-Source: ABdhPJzaRDW7PH4hkD8Yjx/uOud9MZymvRbT6QqTBQp3bTMfCiG+bNXFb4YbR7YmIjI0E5J+khiHjw== X-Received: by 2002:a5d:64c5:: with SMTP id f5mr13417395wri.321.1634888632758; Fri, 22 Oct 2021 00:43:52 -0700 (PDT) Received: from gmail.com (563BB2F5.dsl.pool.telekom.hu. [86.59.178.245]) by smtp.gmail.com with ESMTPSA id i203sm10161968wma.48.2021.10.22.00.43.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 22 Oct 2021 00:43:52 -0700 (PDT) Sender: Ingo Molnar Date: Fri, 22 Oct 2021 09:43:50 +0200 From: Ingo Molnar To: Qi Zheng Cc: Stephen Rothwell , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Peter Zijlstra , Kees Cook , Linux Kernel Mailing List , Linux Next Mailing List Subject: [PATCH] stacktrace: Provide stack_trace_save_tsk() stub in the !CONFIG_STACKTRACE case too Message-ID: References: <20211018172330.379b2061@canb.auug.org.au> <60e736e7-cc37-9fea-a0fb-6628f87e741c@bytedance.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <60e736e7-cc37-9fea-a0fb-6628f87e741c@bytedance.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Qi Zheng wrote: > > > On 10/18/21 2:23 PM, Stephen Rothwell wrote: > > Hi all, > > > > After merging the tip tree, today's linux-next build (x86_64 allnoconfig) > > failed like this: > > > > arch/x86/kernel/process.c: In function '__get_wchan': > > arch/x86/kernel/process.c:950:2: error: implicit declaration of function 'stack_trace_save_tsk' [-Werror=implicit-function-declaration] > > 950 | stack_trace_save_tsk(p, &entry, 1, 0); > > | ^~~~~~~~~~~~~~~~~~~~ > > cc1: some warnings being treated as errors > > > > Caused by commit > > > > bc9bbb81730e ("x86: Fix get_wchan() to support the ORC unwinder") > > > > stack_trace_save_tsk() requires CONFIG_STACKTRACE which is not set for > > this build. > > Maybe get_wchan() can be updated to: > > unsigned long get_wchan(struct task_struct *p) > { > #ifdef CONFIG_STACKTRACE > unsigned long entry = 0; > > stack_trace_save_tsk(p, &entry, 1, 0); > return entry; > #else /* CONFIG_STACKTRACE */ > return 0; > #endif > } And repeat the same ugliness in every single function that happens to use the stack_trace_save_tsk() API?? The correct solution is to define stack_trace_save_tsk() in the !CONFIG_STACKTRACE case too, as the patch below does. Thanks, Ingo ==============================> From: Ingo Molnar Date: Fri, 22 Oct 2021 09:40:27 +0200 Subject: [PATCH] stacktrace: Provide stack_trace_save_tsk() stub in the !CONFIG_STACKTRACE case too The following commit: bc9bbb81730e ("x86: Fix get_wchan() to support the ORC unwinder") Added stack_trace_save_tsk() use to __get_wchan(), while this method is not unconditionally defined: it's not available in the !CONFIG_STACKTRACE case. Give a default implementation that does nothing. Reported-by: Stephen Rothwell Fixes: bc9bbb81730e ("x86: Fix get_wchan() to support the ORC unwinder") Cc: Qi Zheng Cc: Peter Zijlstra Signed-off-by: Ingo Molnar --- include/linux/stacktrace.h | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/include/linux/stacktrace.h b/include/linux/stacktrace.h index 9edecb494e9e..3ccaf599630f 100644 --- a/include/linux/stacktrace.h +++ b/include/linux/stacktrace.h @@ -91,8 +91,19 @@ extern void save_stack_trace_tsk(struct task_struct *tsk, extern int save_stack_trace_tsk_reliable(struct task_struct *tsk, struct stack_trace *trace); extern void save_stack_trace_user(struct stack_trace *trace); + #endif /* !CONFIG_ARCH_STACKWALK */ -#endif /* CONFIG_STACKTRACE */ + +#else /* !CONFIG_STACKTRACE: */ +static inline unsigned int +stack_trace_save_tsk(struct task_struct *task, + unsigned long *store, unsigned int size, + unsigned int skipnr) +{ + return -ENOSYS; +} + +#endif /* !CONFIG_STACKTRACE */ #if defined(CONFIG_STACKTRACE) && defined(CONFIG_HAVE_RELIABLE_STACKTRACE) int stack_trace_save_tsk_reliable(struct task_struct *tsk, unsigned long *store,