From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794061111; b=t6mZm0CZIgSiFWXG1hIb86FMIKmxkGLbnlpwkw77qMkKUAXFD1ztlRF0tNogsNEvqRc9 5wEUA5XF8//xBdsGrg3d09mY975Dd91zNIT/twaun8J/nKn/V5GXj32SW+TG7d5zsuUjA xLE4LTDFJtYGAMFXMovb7c2D5ew3cvPVDBp/nlQmlamG0J/6qImC0vg6Em6509xvQdY7a 6Z2MKpjs9ZsRrgYtyfBnmsNYPDN70y2jzeo/A7/LEgOr8lsnTJ4mGpGBM+s9RN6UBoOlW A55VUjIJo8O/OIjOo4mkaT72rroF7eciqfo1PqEiUn2vyV5OoNLx7vH3Bqqx4Pr7FnQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794061111; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=g38MTfDFINc+qVHXu48y+iGUG+zdZ1pBV1WojDJc1xQ=; b=mSulK62At/ExuKkHRkIez6ls7PXtVwLZYnjRWorW5N3H1ipmD/5FPdv3MEQm9IfSQ+UQ DNSOenqhXgePqae5NK9jRQaNTqSQpiajswl3/cvOqGuwjX/OFt9rl4i8HgXrQwxOgtbCW GjUszf5zuuz7DXInBURfURczBRxt9cyi6q+Ts+cdSibgGYtcZhdBipIO+Q0Td0LnfHQZ3 DjKYiIaKgY/9YCZ2grtfXNUYqq1UCzklOlpG+rW4ZoLPG08K922FCvBRVAzG9xt8gqopr juIkiGw8Dh2MNMXvg0XQeYOhlBuEXIzxBFteDNIam9zutOXdxt/na7G1bP7TzF/tFpw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b="zefXU/do"; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E0C8C606A332; Sat, 7 Nov 2026 14:18:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=zefXU/do Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8275B1F0089F; Sat, 7 Nov 2026 14:18:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1794061110; bh=g38MTfDFINc+qVHXu48y+iGUG+zdZ1pBV1WojDJc1xQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=zefXU/doqzbT8VsV3h5Z+VcZ5Yq19PO1iK8A8VojZV5GDRjIfm3t9WGR1i907EVGQ OqJkkcmuF6snPe5iSttnv4lHg/VUtEvdU4ujOFd6dVX4WMVYSS5ivcEVG4yZDE8MrB RfaJc/sF1zlryKP+N+BgtV7Kq4kOEhrgPhrdkmWk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, kernel test robot , John Ogness , Petr Mladek , Sasha Levin Subject: [PATCH 6.12 0428/1536] nbcon/reboot: Switch NBCON consoles into the emergency mode in emergency_restart() Date: Sat, 7 Nov 2026 08:40:44 -0500 Message-ID: <20261107135009.586756201@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261107134957.653319350@linuxfoundation.org> References: <20261107134957.653319350@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Petr Mladek [ Upstream commit d8e5fc3002294a28af53e97f6c83a35956e738f3 ] When the system is going down a normal way, the NBCON kthreads are flushed and stopped properly via a syscore shutdown callback, see printk_kthreads_shutdown(). One missing piece is emergency_restart() where the kthreads are not stopped. It might be called from several non-panic code paths, e.g. sysrq-o, kdb_reboot(), or some watchdogs. Fix it by explicitly entering the emergency (atomic) mode and trying to flush the consoles there. Note that printk_trigger_flush() must be used instead of pr_flush() because the later is not safe in an atomic context. Reported-by: kernel test robot Closes: https://lore.kernel.org/all/202608061008.48a1e76e-lkp@intel.com/ Suggested-by: John Ogness Reviewed-by: John Ogness Link: https://patch.msgid.link/20261013154141.94016-1-pmladek@suse.com Signed-off-by: Petr Mladek Signed-off-by: Sasha Levin --- kernel/reboot.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/kernel/reboot.c b/kernel/reboot.c index 24c5bc26385af..caab5c86c6e29 100644 --- a/kernel/reboot.c +++ b/kernel/reboot.c @@ -8,6 +8,7 @@ #define pr_fmt(fmt) "reboot: " fmt #include +#include #include #include #include @@ -85,6 +86,14 @@ void emergency_restart(void) { kmsg_dump(KMSG_DUMP_EMERG); system_state = SYSTEM_RESTART; + + /* + * NBCON kthreads won't be flushed and stopped properly in + * the emergency restart. Move them to the atomic mode. + */ + nbcon_cpu_emergency_enter(); + printk_trigger_flush(); + machine_emergency_restart(); } EXPORT_SYMBOL_GPL(emergency_restart); -- 2.53.0