From patchwork Thu Dec 19 07:31:23 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ahmad Fatoum X-Patchwork-Id: 13914603 Received: from metis.whiteo.stw.pengutronix.de (metis.whiteo.stw.pengutronix.de [185.203.201.7]) (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 7EDE314A630 for ; Thu, 19 Dec 2024 07:32:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.203.201.7 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734593545; cv=none; b=p+OJcfVmMiT0+axMZTBG7O+GiO/Ixb5r/Sxek3Rpu2zpzHDTYgAhmpgVVweGQbz6xyeJQlWqsH0W5PTR6ssUTig87uXL1gs8y3pJmtYr0xX6J7HaaJ90s5kJ54uACrmSDw6FW6Npj96PfYurscsrrrLwwU3eJkAbr7ex+wVD8Oc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734593545; c=relaxed/simple; bh=kYgKdKaP/JPHzEu3qpEwsNrhXqPcqBKY/KOWofPl+Ao=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=HWTMzG7Of52rcoqfNs3gJ15ZSc2lKxm7x3KURceoSol1OVWSj9BzzxKPMuDB7sMEOc0aUAT6HKF1vNidBQZw20ZmzNDtF7eXy/20ipB/8nRdOos53H1CWx85I7DFPBaZ4xzTRWfcpuWMMNpz63XkWid+Wevb2McTOqxvYmeIoKM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de; spf=pass smtp.mailfrom=pengutronix.de; arc=none smtp.client-ip=185.203.201.7 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=pengutronix.de Received: from drehscheibe.grey.stw.pengutronix.de ([2a0a:edc0:0:c01:1d::a2]) by metis.whiteo.stw.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1tOB0O-00088X-1Y; Thu, 19 Dec 2024 08:31:32 +0100 Received: from dude05.red.stw.pengutronix.de ([2a0a:edc0:0:1101:1d::54]) by drehscheibe.grey.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1tOB0L-004APp-24; Thu, 19 Dec 2024 08:31:30 +0100 Received: from localhost ([::1] helo=dude05.red.stw.pengutronix.de) by dude05.red.stw.pengutronix.de with esmtp (Exim 4.96) (envelope-from ) id 1tOB0M-00GkbH-0l; Thu, 19 Dec 2024 08:31:30 +0100 From: Ahmad Fatoum Date: Thu, 19 Dec 2024 08:31:23 +0100 Subject: [PATCH 02/11] reboot: reboot, not shutdown, on hw_protection_reboot timeout Precedence: bulk X-Mailing-List: linux-security-module@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20241219-hw_protection-reboot-v1-2-263a0c1df802@pengutronix.de> References: <20241219-hw_protection-reboot-v1-0-263a0c1df802@pengutronix.de> In-Reply-To: <20241219-hw_protection-reboot-v1-0-263a0c1df802@pengutronix.de> To: Daniel Lezcano , Fabio Estevam , "Rafael J. Wysocki" , Zhang Rui , Lukasz Luba , Jonathan Corbet , Serge Hallyn , Liam Girdwood , Mark Brown , Matti Vaittinen , Benson Leung , Tzung-Bi Shih , Guenter Roeck , Rob Herring , Krzysztof Kozlowski , Conor Dooley Cc: linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, linux-doc@vger.kernel.org, linux-security-module@vger.kernel.org, chrome-platform@lists.linux.dev, devicetree@vger.kernel.org, kernel@pengutronix.de, Ahmad Fatoum X-Mailer: b4 0.14.2 X-SA-Exim-Connect-IP: 2a0a:edc0:0:c01:1d::a2 X-SA-Exim-Mail-From: a.fatoum@pengutronix.de X-SA-Exim-Scanned: No (on metis.whiteo.stw.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-security-module@vger.kernel.org hw_protection_shutdown() will kick off an orderly shutdown and if that takes longer than a configurable amount of time, an emergency shutdown will occur. Recently, hw_protection_reboot() was added for those systems that don't implement a proper shutdown and are better served by rebooting and having the boot firmware worry about doing something about the critical condition. On timeout of the orderly reboot of hw_protection_reboot(), the system would go into shutdown, instead of reboot. This is not a good idea, as going into shutdown was explicitly not asked for. Fix this by always doing an emergency reboot if hw_protection_reboot() is called and the orderly reboot takes too long. Fixes: 79fa723ba84c ("reboot: Introduce thermal_zone_device_critical_reboot()") Signed-off-by: Ahmad Fatoum --- kernel/reboot.c | 46 +++++++++++++++++++++++++++++++++++----------- 1 file changed, 35 insertions(+), 11 deletions(-) diff --git a/kernel/reboot.c b/kernel/reboot.c index f92aa66cbfec0f57ded43ba352a39c54d0c24a25..8e3680d36654587b57db44806a3d7b0228b10f67 100644 --- a/kernel/reboot.c +++ b/kernel/reboot.c @@ -932,6 +932,20 @@ void orderly_reboot(void) } EXPORT_SYMBOL_GPL(orderly_reboot); +static const char *hw_protection_action_str(enum hw_protection_action action) +{ + switch (action) { + case HWPROT_ACT_SHUTDOWN: + return "shutdown"; + case HWPROT_ACT_REBOOT: + return "reboot"; + default: + return "undefined"; + } +} + +static enum hw_protection_action hw_failure_emergency_action; + /** * hw_failure_emergency_poweroff_func - emergency poweroff work after a known delay * @work: work_struct associated with the emergency poweroff function @@ -941,21 +955,29 @@ EXPORT_SYMBOL_GPL(orderly_reboot); */ static void hw_failure_emergency_poweroff_func(struct work_struct *work) { + const char *action_str = hw_protection_action_str(hw_failure_emergency_action); + + pr_emerg("Hardware protection timed-out. Trying forced %s\n", + action_str); + /* - * We have reached here after the emergency shutdown waiting period has - * expired. This means orderly_poweroff has not been able to shut off - * the system for some reason. + * We have reached here after the emergency action waiting period has + * expired. This means orderly_poweroff/reboot has not been able to + * shut off the system for some reason. * - * Try to shut down the system immediately using kernel_power_off - * if populated + * Try to shut off the system immediately if possible */ - pr_emerg("Hardware protection timed-out. Trying forced poweroff\n"); - kernel_power_off(); + + if (hw_failure_emergency_action == HWPROT_ACT_REBOOT) + kernel_restart(NULL); + else + kernel_power_off(); /* * Worst of the worst case trigger emergency restart */ - pr_emerg("Hardware protection shutdown failed. Trying emergency restart\n"); + pr_emerg("Hardware protection %s failed. Trying emergency restart\n", + action_str); emergency_restart(); } @@ -963,15 +985,17 @@ static DECLARE_DELAYED_WORK(hw_failure_emergency_poweroff_work, hw_failure_emergency_poweroff_func); /** - * hw_failure_emergency_poweroff - Trigger an emergency system poweroff + * hw_failure_emergency_schedule - Schedule an emergency system shutdown or reboot * * This may be called from any critical situation to trigger a system shutdown * after a given period of time. If time is negative this is not scheduled. */ -static void hw_failure_emergency_poweroff(int poweroff_delay_ms) +static void hw_failure_emergency_schedule(enum hw_protection_action action, + int poweroff_delay_ms) { if (poweroff_delay_ms <= 0) return; + hw_failure_emergency_action = action; schedule_delayed_work(&hw_failure_emergency_poweroff_work, msecs_to_jiffies(poweroff_delay_ms)); } @@ -1009,7 +1033,7 @@ void __hw_protection_shutdown(const char *reason, int ms_until_forced, * Queue a backup emergency shutdown in the event of * orderly_poweroff failure */ - hw_failure_emergency_poweroff(ms_until_forced); + hw_failure_emergency_schedule(action, ms_until_forced); if (action == HWPROT_ACT_REBOOT) orderly_reboot(); else