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 5660111719 for ; Thu, 21 Dec 2023 22:35:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="hUl61hMt" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 16206C433C8; Thu, 21 Dec 2023 22:35:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1703198152; bh=/NkeAv0ndydkXWXgbWX2GDn55RALuyuEPQVFAhgHzWI=; h=Date:To:From:Subject:From; b=hUl61hMtP5eiAjqWDs2z9x+WC+q7FGh8t3KCeJoqnJBHwd2MN7jVVsqLom2hWMxnx fYB5PMmual+DYMzYf+GYz3hGhDqML6bXuOg67be7W3aNoAZwHxl3afo4usog26Shdi N4XARTtEZXcMcxLaOHGtO3IbNjyiQ2JZoitZNs6c= Date: Thu, 21 Dec 2023 14:35:51 -0800 To: mm-commits@vger.kernel.org,pmladek@suse.com,lizhe.67@bytedance.com,lecopzer.chen@mediatek.com,kernelfans@gmail.com,john.ogness@linutronix.de,dianders@chromium.org,akpm@linux-foundation.org From: Andrew Morton Subject: + watchdog-if-panicking-and-we-dumped-everything-dont-re-enable-dumping.patch added to mm-nonmm-unstable branch Message-Id: <20231221223552.16206C433C8@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: watchdog: if panicking and we dumped everything, don't re-enable dumping has been added to the -mm mm-nonmm-unstable branch. Its filename is watchdog-if-panicking-and-we-dumped-everything-dont-re-enable-dumping.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/watchdog-if-panicking-and-we-dumped-everything-dont-re-enable-dumping.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: Douglas Anderson Subject: watchdog: if panicking and we dumped everything, don't re-enable dumping Date: Wed, 20 Dec 2023 13:15:37 -0800 If, as part of handling a hardlockup or softlockup, we've already dumped all CPUs and we're just about to panic, don't reenable dumping and give some other CPU a chance to hop in there and add some confusing logs right as the panic is happening. Link: https://lkml.kernel.org/r/20231220131534.4.Id3a9c7ec2d7d83e4080da6f8662ba2226b40543f@changeid Signed-off-by: Douglas Anderson Cc: John Ogness Cc: Lecopzer Chen Cc: Li Zhe Cc: Petr Mladek Cc: Pingfan Liu Signed-off-by: Andrew Morton --- kernel/watchdog.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/kernel/watchdog.c~watchdog-if-panicking-and-we-dumped-everything-dont-re-enable-dumping +++ a/kernel/watchdog.c @@ -192,7 +192,8 @@ void watchdog_hardlockup_check(unsigned if (sysctl_hardlockup_all_cpu_backtrace) { trigger_allbutcpu_cpu_backtrace(cpu); - clear_bit_unlock(0, &hard_lockup_nmi_warn); + if (!hardlockup_panic) + clear_bit_unlock(0, &hard_lockup_nmi_warn); } if (hardlockup_panic) @@ -548,7 +549,8 @@ static enum hrtimer_restart watchdog_tim if (softlockup_all_cpu_backtrace) { trigger_allbutcpu_cpu_backtrace(smp_processor_id()); - clear_bit_unlock(0, &soft_lockup_nmi_warn); + if (!softlockup_panic) + clear_bit_unlock(0, &soft_lockup_nmi_warn); } add_taint(TAINT_SOFTLOCKUP, LOCKDEP_STILL_OK); _ Patches currently in -mm which might be from dianders@chromium.org are watchdog-hardlockup-adopt-softlockup-logic-avoiding-double-dumps.patch watchdog-softlockup-use-printk_cpu_sync_get_irqsave-to-serialize-reporting.patch watchdog-hardlockup-use-printk_cpu_sync_get_irqsave-to-serialize-reporting.patch watchdog-if-panicking-and-we-dumped-everything-dont-re-enable-dumping.patch