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=-9.8 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,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 877AAC352BE for ; Sat, 18 Apr 2020 20:21:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 679E521D93 for ; Sat, 18 Apr 2020 20:21:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=arista.com header.i=@arista.com header.b="HIlEqOgj" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728773AbgDRUVH (ORCPT ); Sat, 18 Apr 2020 16:21:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56640 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1728707AbgDRUUz (ORCPT ); Sat, 18 Apr 2020 16:20:55 -0400 Received: from mail-wm1-x341.google.com (mail-wm1-x341.google.com [IPv6:2a00:1450:4864:20::341]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 87AAFC061A0C for ; Sat, 18 Apr 2020 13:20:55 -0700 (PDT) Received: by mail-wm1-x341.google.com with SMTP id u127so5679033wmg.1 for ; Sat, 18 Apr 2020 13:20:55 -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=UewK9hpbawAl/WYk+ND4T8F/xnhDTg+TNkaDS8X7FAg=; b=HIlEqOgj2cmtL9KqmWgeEy0gQuJtaVHQ2cHd9TL6LYzeq+/b7CNH9O2AnMvfqwUwvf S0mJeEnt1BlrQs0E0jAyHh3xwJPUVthydthFhyyLPd2/4tMYJ1vbJHerC/BEGfJO2JY5 4XeD++gDBfQv6KfCOl7yU/+ba1E4AkcJxGseQXm0FxDpKK4eqrQswBW2yHMFYEVgv+nO sq/nkqxzhK5qUg+90RWPI5o04/AX1DzPH0WeMv6kvdQBBiy6f4p07p/638a9lOfAGSpI hq3vSlwGfXw67qjsKksztz3PNazbwK+d5zaZdxUWpYfXqzcNDenfCUfNvGd95r0VenNR +Gsw== 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=UewK9hpbawAl/WYk+ND4T8F/xnhDTg+TNkaDS8X7FAg=; b=EIumcojva6uAmG1TeaPIsnuhqT1PwJiTEoikVF3RlT2NTzgz8BYWiLVSnvDGzWSKby AC2dVADHgaDEAg8jiqFYy2Y8m8D0bbHWC5kZ40olUCR1h0SyEGdINWBAARelU5xVsvlJ mQGPLDE+XzCHlAZIfEZEJEW7bfjTSOgHd3EKlVvk43vSUqdLsikL1UvP2Ulv3U/ZDYSM XFob/R049XwpSInGaZmtzZbwXbRekBwuSTM7HwuKu11S04evyl1xL4qMNzPnrs4tGyRw nUQIHy3aq8mF7lHgccT13QNEs2z26xza1/GWg9685UW2rBxE4KSoZM8R2R3MxRXU0xjx H1Ig== X-Gm-Message-State: AGi0PuZneS3Qtl2E0/lwFjoxAcmlAxBg9lZYnlhT3IgYb9v/lofViilR yHye1p9+2rZms3gUuygK4KQFLdniI5g= X-Google-Smtp-Source: APiQypKR5Y1qOUmKwsHhnH8t7/xEWQdJ92qlq/z6zpVNikpJ4d3OGf+F5GDVmWR8X/evMGIV0sK2CA== X-Received: by 2002:a1c:7d90:: with SMTP id y138mr10245638wmc.121.1587241254076; Sat, 18 Apr 2020 13:20:54 -0700 (PDT) Received: from localhost.localdomain ([2a02:8084:e84:2480:228:f8ff:fe6f:83a8]) by smtp.gmail.com with ESMTPSA id m1sm31735255wro.64.2020.04.18.13.20.52 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 18 Apr 2020 13:20:53 -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 , Daniel Thompson , Douglas Anderson , Jason Wessel , kgdb-bugreport@lists.sourceforge.net Subject: [PATCHv3 47/50] kdb: Don't play with console_loglevel Date: Sat, 18 Apr 2020 21:19:41 +0100 Message-Id: <20200418201944.482088-48-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 Print the stack trace with KERN_EMERG - it should be always visible. Playing with console_loglevel is a bad idea as there may be more messages printed than wanted. Also the stack trace might be not printed at all if printk() was deferred and console_loglevel was raised back before the trace got flushed. Unfortunately, after rebasing on commit 2277b492582d ("kdb: Fix stack crawling on 'running' CPUs that aren't the master"), kdb_show_stack() uses now kdb_dump_stack_on_cpu(), which for now won't be converted as it uses dump_stack() instead of show_stack(). Convert for now the branch that uses show_stack() and remove console_loglevel exercise from that case. Cc: Daniel Thompson Cc: Douglas Anderson Cc: Jason Wessel Cc: kgdb-bugreport@lists.sourceforge.net Acked-by: Daniel Thompson Reviewed-by: Douglas Anderson Signed-off-by: Dmitry Safonov --- kernel/debug/kdb/kdb_bt.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) diff --git a/kernel/debug/kdb/kdb_bt.c b/kernel/debug/kdb/kdb_bt.c index 3de0cc780c16..43f5dcd2b9ac 100644 --- a/kernel/debug/kdb/kdb_bt.c +++ b/kernel/debug/kdb/kdb_bt.c @@ -21,17 +21,18 @@ static void kdb_show_stack(struct task_struct *p, void *addr) { - int old_lvl = console_loglevel; - - console_loglevel = CONSOLE_LOGLEVEL_MOTORMOUTH; kdb_trap_printk++; - if (!addr && kdb_task_has_cpu(p)) + if (!addr && kdb_task_has_cpu(p)) { + int old_lvl = console_loglevel; + + console_loglevel = CONSOLE_LOGLEVEL_MOTORMOUTH; kdb_dump_stack_on_cpu(kdb_process_cpu(p)); - else - show_stack(p, addr); + console_loglevel = old_lvl; + } else { + show_stack_loglvl(p, addr, KERN_EMERG); + } - console_loglevel = old_lvl; kdb_trap_printk--; } -- 2.26.0