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 65F3147A64; Mon, 1 Apr 2024 17:07:47 +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=1711991267; cv=none; b=bJEqyJFKbsUg8g+9Mtoel9Cyq+1cZnebPH8jUd9SrHsoyNS2a26YY/hwrPH0qh5m2CItqb1e6Lk8kyFSPI7ir3NQWn/VMcHWrbNLe0qBaLivpTMU+gksA+2kyqmuvmUvtjfCg+Y6OMemmqNLlB4yrcBhPGMmKDbQiCDjofZ9gv0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711991267; c=relaxed/simple; bh=GhDefM2vhU2HhJexO6PZ5nCmy3+UxykQugJ0URUYnJ8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=jxN+TigCADLgzFt6YLRsZ+rfEtdrP1F7vCuDNGCrTPQvRFPKLdz0RzN0nhGDTr8vZ8gtEPuEAU7aVTtxwEYRB1O6sbpyX9jSU9ucNZ95KraEB4BspO8veMBq+oTZ5neB+JVR//ajXSUMFETqV/L95RCU6o765pdcVgi2GTS2YdQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=LrRc/klZ; 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="LrRc/klZ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 80437C433C7; Mon, 1 Apr 2024 17:07:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1711991267; bh=GhDefM2vhU2HhJexO6PZ5nCmy3+UxykQugJ0URUYnJ8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LrRc/klZJkfsQ/yhZvS1vXVQYNQccwUT5rqFHNhzhp6N9fjpoSQw6wKjV/8ooXJl8 pJfYL/hz83d8UhDu865wYf0Km+1vUHxxlSNE31Olcr76T142QS9c7f9wlt2HFJcsdv T5r9ud4Lxzv2R1TZfdmV4evsQnP1vCkOsYQ2r6Ls= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Mukesh Ojha , John Ogness , Petr Mladek , Sasha Levin Subject: [PATCH 6.1 184/272] printk: Update @console_may_schedule in console_trylock_spinning() Date: Mon, 1 Apr 2024 17:46:14 +0200 Message-ID: <20240401152536.561886618@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240401152530.237785232@linuxfoundation.org> References: <20240401152530.237785232@linuxfoundation.org> User-Agent: quilt/0.67 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 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: John Ogness [ Upstream commit 8076972468584d4a21dab9aa50e388b3ea9ad8c7 ] console_trylock_spinning() may takeover the console lock from a schedulable context. Update @console_may_schedule to make sure it reflects a trylock acquire. Reported-by: Mukesh Ojha Closes: https://lore.kernel.org/lkml/20240222090538.23017-1-quic_mojha@quicinc.com Fixes: dbdda842fe96 ("printk: Add console owner and waiter logic to load balance console writes") Signed-off-by: John Ogness Reviewed-by: Mukesh Ojha Reviewed-by: Petr Mladek Link: https://lore.kernel.org/r/875xybmo2z.fsf@jogness.linutronix.de Signed-off-by: Petr Mladek Signed-off-by: Sasha Levin --- kernel/printk/printk.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index c55ee859dbd08..0ae06d5046bb0 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -1947,6 +1947,12 @@ static int console_trylock_spinning(void) */ mutex_acquire(&console_lock_dep_map, 0, 1, _THIS_IP_); + /* + * Update @console_may_schedule for trylock because the previous + * owner may have been schedulable. + */ + console_may_schedule = 0; + return 1; } -- 2.43.0