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 6B1C325F7A5; Thu, 17 Apr 2025 17:56:37 +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=1744912597; cv=none; b=IsZHzO0hOno675zuKni7ZjmX4+Eh6tv1JF2ZxYiC+hiNN4UVI8ugcbUar4uCXmINHfaqw6w6Hdh0qVBKQlN8KQx6NI1FqNQfvk50MkJzHvSMNqKwQDXrCU4A8+xv2i6oG2quBg6QCP2Ll4Pj+jlU33+tKbm3GFhsSxlFiJAylEQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744912597; c=relaxed/simple; bh=8UYTc2Tat1M5vMyaAg6bcEUcbpjHrLFzycHMkURiZrc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=OVHOwDk6Kn+GEY2cgPuBGsT43sC+qtrkCqpyYhr9sa2sMnj23oAvzLnYqtV+MsDx7CA/3FZciNioM6jIsIriG1DwlX04FH1+KCKGeMjAMZn7o392kChofQa0kZQL2cnxo7mVEycTFuCzQ5rhVmVCaqv8bLDBh6an7I0C7aQufn0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=oGlddCej; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="oGlddCej" Received: by smtp.kernel.org (Postfix) with ESMTPSA id F1DA3C4CEE4; Thu, 17 Apr 2025 17:56:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1744912597; bh=8UYTc2Tat1M5vMyaAg6bcEUcbpjHrLFzycHMkURiZrc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=oGlddCej4FWl7qL2yJIMmA0JPKGebqhwKSRgL0j7Y3HanbSr9FhxSgRkoxFnIY8C1 CgAQm1FpG9VBDxTbs6wKyAfnXDX5cyhMiTmuvAiIjcVKTpHw5loCx6PwmMrrMcUczf YQ+3CG0i22S8c940FBxAUDNNTnnWQiYsHgAZSV3I= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, "Paul E. McKenney" , John Ogness , Petr Mladek , Steven Rostedt , Sergey Senozhatsky , Boqun Feng , Sasha Levin Subject: [PATCH 6.14 062/449] Flush console log from kernel_power_off() Date: Thu, 17 Apr 2025 19:45:50 +0200 Message-ID: <20250417175120.487511961@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250417175117.964400335@linuxfoundation.org> References: <20250417175117.964400335@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Paul E. McKenney [ Upstream commit 6ea9a1781c70a8be1fcdc49134fc1bf4baba8bca ] Kernels built with CONFIG_PREEMPT_RT=y can lose significant console output and shutdown time, which hides shutdown-time RCU issues from rcutorture. Therefore, make pr_flush() public and invoke it after then last print in kernel_power_off(). [ paulmck: Apply John Ogness feedback. ] [ paulmck: Appy Sebastian Andrzej Siewior feedback. ] [ paulmck: Apply kernel test robot feedback. ] Signed-off-by: Paul E. McKenney Reviewed-by: John Ogness Reviewed-by: Petr Mladek Cc: Steven Rostedt Cc: Sergey Senozhatsky Link: https://lore.kernel.org/r/5f743488-dc2a-4f19-bdda-cf50b9314832@paulmck-laptop Signed-off-by: Boqun Feng Signed-off-by: Sasha Levin --- include/linux/printk.h | 6 ++++++ kernel/printk/printk.c | 4 +--- kernel/reboot.c | 1 + 3 files changed, 8 insertions(+), 3 deletions(-) diff --git a/include/linux/printk.h b/include/linux/printk.h index 4217a9f412b26..5b462029d03c1 100644 --- a/include/linux/printk.h +++ b/include/linux/printk.h @@ -207,6 +207,7 @@ void printk_legacy_allow_panic_sync(void); extern bool nbcon_device_try_acquire(struct console *con); extern void nbcon_device_release(struct console *con); void nbcon_atomic_flush_unsafe(void); +bool pr_flush(int timeout_ms, bool reset_on_progress); #else static inline __printf(1, 0) int vprintk(const char *s, va_list args) @@ -315,6 +316,11 @@ static inline void nbcon_atomic_flush_unsafe(void) { } +static inline bool pr_flush(int timeout_ms, bool reset_on_progress) +{ + return true; +} + #endif bool this_cpu_in_panic(void); diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index 07668433644b8..057db78876cd9 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -2461,7 +2461,6 @@ asmlinkage __visible int _printk(const char *fmt, ...) } EXPORT_SYMBOL(_printk); -static bool pr_flush(int timeout_ms, bool reset_on_progress); static bool __pr_flush(struct console *con, int timeout_ms, bool reset_on_progress); #else /* CONFIG_PRINTK */ @@ -2474,7 +2473,6 @@ static bool __pr_flush(struct console *con, int timeout_ms, bool reset_on_progre static u64 syslog_seq; -static bool pr_flush(int timeout_ms, bool reset_on_progress) { return true; } static bool __pr_flush(struct console *con, int timeout_ms, bool reset_on_progress) { return true; } #endif /* CONFIG_PRINTK */ @@ -4466,7 +4464,7 @@ static bool __pr_flush(struct console *con, int timeout_ms, bool reset_on_progre * Context: Process context. May sleep while acquiring console lock. * Return: true if all usable printers are caught up. */ -static bool pr_flush(int timeout_ms, bool reset_on_progress) +bool pr_flush(int timeout_ms, bool reset_on_progress) { return __pr_flush(NULL, timeout_ms, reset_on_progress); } diff --git a/kernel/reboot.c b/kernel/reboot.c index f348f1ba9e226..9461b6b0baa3a 100644 --- a/kernel/reboot.c +++ b/kernel/reboot.c @@ -704,6 +704,7 @@ void kernel_power_off(void) migrate_to_reboot_cpu(); syscore_shutdown(); pr_emerg("Power down\n"); + pr_flush(1000, true); kmsg_dump(KMSG_DUMP_SHUTDOWN); machine_power_off(); } -- 2.39.5