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 27D9F2BF011 for ; Thu, 3 Jul 2025 22:41:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751582502; cv=none; b=M2UIkHS6BKYsuzn9qzVKHTGumVvYrr17DPqJDN6/4ZZPM/9Ebd8BAJbXTeheSuyAf3+OBvYsgbaYR11IZSfHD2TxLX7hYX5u4nkY/Fa0xQ+Te47MFY0IoqyLlK4nyKfE4L+2nmIgGiuyZfeVxoFqrJacPF7H8nWfj0TL1/Xc79Q= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751582502; c=relaxed/simple; bh=yctivoqnRxfYwR9RVYamq6KWHQErlcHCJvYvXjlv5Ng=; h=Date:To:From:Subject:Message-Id; b=k0sATUGlgJezyQMKN1lMrslitTzGDsfyGRz/ALGtz7ikWa9XXRKAe68r8gOS3Pm1uPvI/NqPnFivYBZ01F/a2apSKeUlHPsI+5NmuywGZJDsQk6YUX7Viwt/1CnDewb6/ENAyNFKvEyXDpYcYzBCxwDVBz7u/4+IRMA4RalJiBU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=UER7o36R; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="UER7o36R" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8F9A6C4CEED; Thu, 3 Jul 2025 22:41:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1751582501; bh=yctivoqnRxfYwR9RVYamq6KWHQErlcHCJvYvXjlv5Ng=; h=Date:To:From:Subject:From; b=UER7o36RaoCzHIl/bP1wgurdacOGmiSRmveod9uwAcL41M0WYNH63mN9YYcdguAUE KOHDrgFNtTXvotQ8/jxivBBfH1f+OMhxjVgdq0sd1qAc7Y8sHCeA3Crhz5xzjl6DL9 3Tshy9t2P9HQ69UR8RjyNexGuM2rBHlUwKRWMB7s= Date: Thu, 03 Jul 2025 15:41:40 -0700 To: mm-commits@vger.kernel.org,rostedt@goodmis.org,pmladek@suse.com,paulmck@kernel.org,lance.yang@linux.dev,john.ogness@linutronix.de,corbet@lwn.net,feng.tang@linux.alibaba.com,akpm@linux-foundation.org From: Andrew Morton Subject: + panic-add-note-that-panic_print-sysctl-interface-is-deprecated.patch added to mm-nonmm-unstable branch Message-Id: <20250703224141.8F9A6C4CEED@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: panic: add note that panic_print sysctl interface is deprecated has been added to the -mm mm-nonmm-unstable branch. Its filename is panic-add-note-that-panic_print-sysctl-interface-is-deprecated.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/panic-add-note-that-panic_print-sysctl-interface-is-deprecated.patch This patch will later appear in the mm-nonmm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Feng Tang Subject: panic: add note that panic_print sysctl interface is deprecated Date: Thu, 3 Jul 2025 10:10:04 +0800 Add a dedicated core parameter 'panic_console_replay' for controlling console replay, and add note that 'panic_print' sysctl interface will be obsoleted by 'panic_sys_info' and 'panic_console_replay'. When it happens, the SYS_INFO_PANIC_CONSOLE_REPLAY can be removed as well. Link: https://lkml.kernel.org/r/20250703021004.42328-6-feng.tang@linux.alibaba.com Signed-off-by: Feng Tang Suggested-by: Petr Mladek Cc: John Ogness Cc: Jonathan Corbet Cc: Lance Yang Cc: "Paul E . McKenney" Cc: Steven Rostedt Signed-off-by: Andrew Morton --- Documentation/admin-guide/kernel-parameters.txt | 4 ++ kernel/panic.c | 21 ++++++++------ 2 files changed, 17 insertions(+), 8 deletions(-) --- a/Documentation/admin-guide/kernel-parameters.txt~panic-add-note-that-panic_print-sysctl-interface-is-deprecated +++ a/Documentation/admin-guide/kernel-parameters.txt @@ -4578,6 +4578,10 @@ This is a human readable alternative to the 'panic_print' option. + panic_console_replay + When panic happens, replay all kernel messages on + consoles at the end of panic. + parkbd.port= [HW] Parallel port number the keyboard adapter is connected to, default is 0. Format: --- a/kernel/panic.c~panic-add-note-that-panic_print-sysctl-interface-is-deprecated +++ a/kernel/panic.c @@ -64,6 +64,7 @@ int panic_on_warn __read_mostly; unsigned long panic_on_taint; bool panic_on_taint_nousertaint = false; static unsigned int warn_limit __read_mostly; +static bool panic_console_replay; bool panic_triggering_all_cpu_backtrace; @@ -77,6 +78,13 @@ ATOMIC_NOTIFIER_HEAD(panic_notifier_list EXPORT_SYMBOL(panic_notifier_list); #ifdef CONFIG_SYSCTL +static int sysctl_panic_print_handler(const struct ctl_table *table, int write, + void *buffer, size_t *lenp, loff_t *ppos) +{ + pr_info_once("Kernel: 'panic_print' sysctl interface will be obsoleted by both 'panic_sys_info' and 'panic_console_replay'\n"); + return proc_doulongvec_minmax(table, write, buffer, lenp, ppos); +} + static const struct ctl_table kern_panic_table[] = { #ifdef CONFIG_SMP { @@ -108,7 +116,7 @@ static const struct ctl_table kern_panic .data = &panic_print, .maxlen = sizeof(unsigned long), .mode = 0644, - .proc_handler = proc_doulongvec_minmax, + .proc_handler = sysctl_panic_print_handler, }, { .procname = "panic_on_warn", @@ -247,12 +255,6 @@ void nmi_panic(struct pt_regs *regs, con } EXPORT_SYMBOL(nmi_panic); -static void panic_console_replay(void) -{ - if (panic_print & SYS_INFO_PANIC_CONSOLE_REPLAY) - console_flush_on_panic(CONSOLE_REPLAY_ALL); -} - void check_panic_on_warn(const char *origin) { unsigned int limit; @@ -427,7 +429,9 @@ void panic(const char *fmt, ...) debug_locks_off(); console_flush_on_panic(CONSOLE_FLUSH_PENDING); - panic_console_replay(); + if ((panic_print & SYS_INFO_PANIC_CONSOLE_REPLAY) || + panic_console_replay) + console_flush_on_panic(CONSOLE_REPLAY_ALL); if (!panic_blink) panic_blink = no_blink; @@ -869,6 +873,7 @@ core_param(panic_print, panic_print, ulo core_param(pause_on_oops, pause_on_oops, int, 0644); core_param(panic_on_warn, panic_on_warn, int, 0644); core_param(crash_kexec_post_notifiers, crash_kexec_post_notifiers, bool, 0644); +core_param(panic_console_replay, panic_console_replay, bool, 0644); static int __init oops_setup(char *s) { _ Patches currently in -mm which might be from feng.tang@linux.alibaba.com are panic-clean-up-code-for-console-replay.patch panic-generalize-panic_prints-function-to-show-sys-info.patch panic-add-panic_sys_info-sysctl-to-take-human-readable-string-parameter.patch panic-add-panic_sys_info=-setup-option-for-kernel-cmdline.patch panic-add-note-that-panic_print-sysctl-interface-is-deprecated.patch