From nobody Fri Dec 19 15:33:15 2025 Received: from mail-pl1-f173.google.com (mail-pl1-f173.google.com [209.85.214.173]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DA6634AF63 for ; Wed, 20 Dec 2023 21:17:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=chromium.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=chromium.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="WMsXp5la" Received: by mail-pl1-f173.google.com with SMTP id d9443c01a7336-1d3ddccfaffso1323145ad.1 for ; Wed, 20 Dec 2023 13:17:13 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1703107033; x=1703711833; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=sGegIddggKFG/zutIaei4eHzxrpz6/dja4W8/BctOAU=; b=WMsXp5lad1ptNXHEjUl8VA87VrrCWANP2+oOSskHvW08BCjLlInH3WWbGorhzR5IKG Q3t95JdFtKdYbMRYuP6lCmOSzzjDOtGuQwzIr0F2QKrF6hsQv/uRi3IUn7p5uYwqrV4x u2e1M/EpEU/NXfkzSPDrGyiLFplp2ZLpYLOJA= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1703107033; x=1703711833; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=sGegIddggKFG/zutIaei4eHzxrpz6/dja4W8/BctOAU=; b=NHZN/j2xGHI8SbJe/k5aOVmelUqpvEv7hjTXXjriSUThpciRRGFBSlrdjuDcwtVIUV 4aBmjcux0OBrqlhe9TofySHhSSM7uKwBY75MKScWcM5uMMJDf1MDfZaky35sm6GaP0Sh hUO1vOcziL/VoekAjJJo9eEGD3Arl2y4s/0o4KA4Jcr4oXEUM8tPaONIHP/lKflrw/Sv MpxR5n+mC5V6yZl8ohgNglLYvrmKt6FKAJB+gZNWyUT5D7VWngmuRkGTLgj19IUwFcpP diBRLtEty5VI7BNlvbQJbnIr6I3IYBsPBq+epuFtRcFdZ6qGZr2UGbTKPl9R42YKH4tZ 0Q+w== X-Gm-Message-State: AOJu0Yy/ax01Ab5qBh6KgRqkg6F7Z3XK0sGkvrvXGn4N0q/Vgk0fK5AV SjFmpyKKaN1i/gGW2jsYml9lyw== X-Google-Smtp-Source: AGHT+IEePv04N2Xkrvd8k65DZuDoY0n0riLwskKakblHowU4xsnnlhRcp1chgs2Vk6H2fJPV3kaKjw== X-Received: by 2002:a17:902:e847:b0:1d0:acfc:a653 with SMTP id t7-20020a170902e84700b001d0acfca653mr23942838plg.84.1703107033190; Wed, 20 Dec 2023 13:17:13 -0800 (PST) Received: from tictac2.mtv.corp.google.com ([2620:15c:9d:2:5a22:d46c:eec1:e5d4]) by smtp.gmail.com with ESMTPSA id u10-20020a170902b28a00b001d3dfebc05esm175023plr.21.2023.12.20.13.17.11 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 20 Dec 2023 13:17:12 -0800 (PST) From: Douglas Anderson To: Andrew Morton Cc: Petr Mladek , Li Zhe , Pingfan Liu , John Ogness , Lecopzer Chen , Douglas Anderson , linux-kernel@vger.kernel.org Subject: [PATCH 4/4] watchdog: If panicking and we dumped everything, don't re-enable dumping Date: Wed, 20 Dec 2023 13:15:37 -0800 Message-ID: <20231220131534.4.Id3a9c7ec2d7d83e4080da6f8662ba2226b40543f@changeid> X-Mailer: git-send-email 2.43.0.472.g3155946c3a-goog In-Reply-To: <20231220211640.2023645-1-dianders@chromium.org> References: <20231220211640.2023645-1-dianders@chromium.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" 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. Signed-off-by: Douglas Anderson --- kernel/watchdog.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/kernel/watchdog.c b/kernel/watchdog.c index 11f9577accca..81a8862295d6 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -192,7 +192,8 @@ void watchdog_hardlockup_check(unsigned int cpu, struct= pt_regs *regs) =20 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); } =20 if (hardlockup_panic) @@ -548,7 +549,8 @@ static enum hrtimer_restart watchdog_timer_fn(struct hr= timer *hrtimer) =20 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); } =20 add_taint(TAINT_SOFTLOCKUP, LOCKDEP_STILL_OK); --=20 2.43.0.472.g3155946c3a-goog