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 6E52E140E3D; Thu, 11 Apr 2024 10:18:47 +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=1712830727; cv=none; b=P0CEl6JgNr2F/Pt2s27973BWBt4A29+koZzrZu9lVaYrhqNkB5pouywgN3jquMZaUSFkO1t/5hbnN1jSMOTgFW9nZNHZjKINkETTb73EnQ5iV30nfincQPZYZDSXOoLYjVlUU+FVIBxnNQ/lnEhknPOT1+KshowV6dc+GCMbjMc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712830727; c=relaxed/simple; bh=hgl3E0tupiuzSLFq45IhqZwz5LHpYUitZ/XcrUzGREw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=RKoRNCuNzY9W23atFU5bLgSQbzweB2t6IO2ckSugprFfzYgs8WPoWn3DJxDFT+pE3SSNRoBgDqDRarnWCed88zgApOQyEH+f3urqYnimhDVl+sv8Le+CahzaM+pYyxrEcRC1eY3cXUQKP49h2fMJ6bqHIM2JAlIZwcWJa2VSYkQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=VP6dqYdX; 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="VP6dqYdX" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E8E99C433F1; Thu, 11 Apr 2024 10:18:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1712830727; bh=hgl3E0tupiuzSLFq45IhqZwz5LHpYUitZ/XcrUzGREw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VP6dqYdXgUrnMJGR3yYZgmm6Rbr9BHX9rYGxgRomR3h81M1FlQkcasnWq8I9ZrtBh FTe0Mo7Je58gnoi7F4rVUo+0QjzAoYMhQf+N6/8HSVDVTnUnTlAPHH+6BgS2Ragfka 58CcpfCdZ1DBTtCdHJTV/SnEP25hf2k2dU3zBbKc= 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 5.4 096/215] printk: Update @console_may_schedule in console_trylock_spinning() Date: Thu, 11 Apr 2024 11:55:05 +0200 Message-ID: <20240411095427.785439974@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240411095424.875421572@linuxfoundation.org> References: <20240411095424.875421572@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 5.4-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 bb2198b40756d..ae1a97dd0c3cb 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -1787,6 +1787,12 @@ 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