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=-9.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 9641FC352BE for ; Sat, 18 Apr 2020 20:22:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 726F421D93 for ; Sat, 18 Apr 2020 20:22:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=arista.com header.i=@arista.com header.b="UmUB6tg2" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728933AbgDRUWx (ORCPT ); Sat, 18 Apr 2020 16:22:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56392 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1728334AbgDRUUA (ORCPT ); Sat, 18 Apr 2020 16:20:00 -0400 Received: from mail-wr1-x443.google.com (mail-wr1-x443.google.com [IPv6:2a00:1450:4864:20::443]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7BF19C061A0F for ; Sat, 18 Apr 2020 13:20:00 -0700 (PDT) Received: by mail-wr1-x443.google.com with SMTP id g13so5130121wrb.8 for ; Sat, 18 Apr 2020 13:20:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arista.com; s=googlenew; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=zimCygk/GteosIyZqYA22VX02uWVm0axmp2+cSyxEk0=; b=UmUB6tg2COFkhKDuApMoEkNTExQQ8zWlCYHCTwLkIEdbL36WyQ3PYYgOKLegDh6d13 DzYw8GkhIIH0MJVWi/dBd6XYZDvflywyb0bhoIeZla+jfYR8B2tdrAMdeVXfnuujTkQN QhZADBr0lPCqEOTst6yj5MWFK/Pi6kqOKUakB7xWdpHdcXwF/eL9RIFDgnAOwuMTYziS uBj1R6ECLpqqE3PysHGFOz5Q/ZjNLmvglWySYgJUjoAEO3vO4h6QkExwulCBUDSXri1A 5+4uxdC+Bsu5JoQi5294pfVzGeRFeSpgGOYEWLGkziQnZdoymCZTDTsvOia8zJCo5dQG qt/w== 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=zimCygk/GteosIyZqYA22VX02uWVm0axmp2+cSyxEk0=; b=nB7OpxtyYxwNnf+Wfq/CHkK6y8QGYYUfIZgg6EsZizktKyeLbr3afRpMEyYQmUAOcU OObRJiI/ZcJRuHDbOvkF2oDqtSIMU0wt2bQ5KktH7nJUEsnKfdoqGz4pNqHlH1c3iq5g rtjwQlFp7AtmtLQP6OKa5J0Wn5H0rNAqVtuP7r3oRBXAfIcLbFtYYph5NS12+b5lW3Ww 2ug5m6OnkU3yDaB6Gg0nVtYvZy59H8YaLIsucv7zMVd508R2BW8GzPM6K0PMqk+v5Ph5 w822e/3GTUOEPPGcJmkgISRVQXNqZmMrGUu6TG4OEu6Nt1jMICH8sYLtwj2bQWUaCBmX v+RA== X-Gm-Message-State: AGi0PuZAAmq0N1dqqjoqDrPJVsLxBgghxhN2uzE0l1QmQgXoEdQZq87u QPL+ChDb5epcvKDMT5FnkoxsIuFz7nQ= X-Google-Smtp-Source: APiQypIULAsyj4ToagbxJztVoEGMoFCVHOReiXnPFqUE3Mk26kvhIwJXZWTW9OZPiBDfvBni1MyhFA== X-Received: by 2002:a5d:6a04:: with SMTP id m4mr11199116wru.326.1587241198993; Sat, 18 Apr 2020 13:19:58 -0700 (PDT) Received: from localhost.localdomain ([2a02:8084:e84:2480:228:f8ff:fe6f:83a8]) by smtp.gmail.com with ESMTPSA id m1sm31735255wro.64.2020.04.18.13.19.57 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 18 Apr 2020 13:19:58 -0700 (PDT) From: Dmitry Safonov To: linux-kernel@vger.kernel.org Cc: Dmitry Safonov <0x7f454c46@gmail.com>, Dmitry Safonov , Andrew Morton , Greg Kroah-Hartman , Ingo Molnar , Jiri Slaby , Petr Mladek , Sergey Senozhatsky , Steven Rostedt , Tetsuo Handa , Russell King , Will Deacon , linux-arm-kernel@lists.infradead.org, clang-built-linux@googlegroups.com Subject: [PATCHv3 06/50] arm: Add loglvl to dump_backtrace() Date: Sat, 18 Apr 2020 21:19:00 +0100 Message-Id: <20200418201944.482088-7-dima@arista.com> X-Mailer: git-send-email 2.26.0 In-Reply-To: <20200418201944.482088-1-dima@arista.com> References: <20200418201944.482088-1-dima@arista.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Currently, the log-level of show_stack() depends on a platform realization. It creates situations where the headers are printed with lower log level or higher than the stacktrace (depending on a platform or user). Furthermore, it forces the logic decision from user to an architecture side. In result, some users as sysrq/kdb/etc are doing tricks with temporary rising console_loglevel while printing their messages. And in result it not only may print unwanted messages from other CPUs, but also omit printing at all in the unlucky case where the printk() was deferred. Introducing log-level parameter and KERN_UNSUPPRESSED [1] seems an easier approach than introducing more printk buffers. Also, it will consolidate printings with headers. Add log level argument to dump_backtrace() as a preparation for introducing show_stack_loglvl(). As a good side-effect __die() now prints not only "Stack:" header with KERN_EMERG, but the backtrace itself. Cc: Russell King Cc: Will Deacon Cc: linux-arm-kernel@lists.infradead.org Cc: clang-built-linux@googlegroups.com [1]: https://lore.kernel.org/lkml/20190528002412.1625-1-dima@arista.com/T/#u Signed-off-by: Dmitry Safonov --- arch/arm/kernel/traps.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c index 685e17c2e275..0f09ace18e6c 100644 --- a/arch/arm/kernel/traps.c +++ b/arch/arm/kernel/traps.c @@ -202,17 +202,19 @@ static void dump_instr(const char *lvl, struct pt_regs *regs) } #ifdef CONFIG_ARM_UNWIND -static inline void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk) +static inline void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk, + const char *loglvl) { - unwind_backtrace(regs, tsk, KERN_DEFAULT); + unwind_backtrace(regs, tsk, loglvl); } #else -static void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk) +static void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk, + const char *loglvl) { unsigned int fp, mode; int ok = 1; - printk("Backtrace: "); + printk("%sBacktrace: ", loglvl); if (!tsk) tsk = current; @@ -239,13 +241,13 @@ static void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk) pr_cont("\n"); if (ok) - c_backtrace(fp, mode, NULL); + c_backtrace(fp, mode, loglvl); } #endif void show_stack(struct task_struct *tsk, unsigned long *sp) { - dump_backtrace(NULL, tsk); + dump_backtrace(NULL, tsk, KERN_DEFAULT); barrier(); } @@ -289,7 +291,7 @@ static int __die(const char *str, int err, struct pt_regs *regs) if (!user_mode(regs) || in_interrupt()) { dump_mem(KERN_EMERG, "Stack: ", regs->ARM_sp, THREAD_SIZE + (unsigned long)task_stack_page(tsk)); - dump_backtrace(regs, tsk); + dump_backtrace(regs, tsk, KERN_EMERG); dump_instr(KERN_EMERG, regs); } -- 2.26.0