From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 4F9CF6AB9 for ; Wed, 23 Mar 2022 23:07:04 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 12C6AC340E8; Wed, 23 Mar 2022 23:07:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1648076824; bh=H2dPfd3XTMtkFe6pJ9g4Atn9PbMHvHVNfh5PXFKKuVE=; h=Date:To:From:In-Reply-To:Subject:From; b=M3UsBFI1raGgI8Slo7l6iiKzJdXOwfmRwUimeWAIbnJuHNgp5XykX4FDAJXL6K1WW om4UB8Bsh/UuM3Y5iRhk4Lo6fXVxSIUtmhplc4gUKCFqFTfXyos+XFFS3KbwK+pius 89AEhdEGpuL/fXqmP42iewCPI96+DIif/rnDQO7w= Date: Wed, 23 Mar 2022 16:07:03 -0700 To: yzaikin@google.com,siglesias@igalia.com,mcgrof@kernel.org,keescook@chromium.org,feng.tang@intel.com,gpiccoli@igalia.com,akpm@linux-foundation.org,patches@lists.linux.dev,linux-mm@kvack.org,mm-commits@vger.kernel.org,torvalds@linux-foundation.org,akpm@linux-foundation.org From: Andrew Morton In-Reply-To: <20220323160453.65922ced539cbf445b191555@linux-foundation.org> Subject: [patch 35/41] docs: sysctl/kernel: add missing bit to panic_print Message-Id: <20220323230704.12C6AC340E8@smtp.kernel.org> Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: From: "Guilherme G. Piccoli" Subject: docs: sysctl/kernel: add missing bit to panic_print Patch series "Some improvements on panic_print". This is a mix of a documentation fix with some additions to the "panic_print" syscall / parameter. The goal here is being able to collect all CPUs backtraces during a panic event and also to enable "panic_print" in a kdump event - details of the reasoning and design choices in the patches. This patch (of 3): Commit de6da1e8bcf0 ("panic: add an option to replay all the printk message in buffer") added a new bit to the sysctl/kernel parameter "panic_print", but the documentation was added only in kernel-parameters.txt, not in the sysctl guide. Fix it here by adding bit 5 to sysctl admin-guide documentation. [rdunlap@infradead.org: fix table format warning] Link: https://lkml.kernel.org/r/20220109055635.6999-1-rdunlap@infradead.org Link: https://lkml.kernel.org/r/20211109202848.610874-1-gpiccoli@igalia.com Link: https://lkml.kernel.org/r/20211109202848.610874-2-gpiccoli@igalia.com Fixes: de6da1e8bcf0 ("panic: add an option to replay all the printk message in buffer") Signed-off-by: Guilherme G. Piccoli Reviewed-by: Feng Tang Cc: Luis Chamberlain Cc: Kees Cook Cc: Iurii Zaikin Cc: Samuel Iglesias Gonsalvez Signed-off-by: Andrew Morton --- Documentation/admin-guide/sysctl/kernel.rst | 1 + 1 file changed, 1 insertion(+) --- a/Documentation/admin-guide/sysctl/kernel.rst~docs-sysctl-kernel-add-missing-bit-to-panic_print +++ a/Documentation/admin-guide/sysctl/kernel.rst @@ -806,6 +806,7 @@ bit 1 print system memory info bit 2 print timer info bit 3 print locks info if ``CONFIG_LOCKDEP`` is on bit 4 print ftrace buffer +bit 5 print all printk messages in buffer ===== ============================================ So for example to print tasks and memory info on panic, user can:: _