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 C4B991C2DC8; Wed, 19 Mar 2025 14:34:50 +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=1742394890; cv=none; b=p9He7xDOEyQn7aeypzsHs1lmUfNgOMNlgFalSfn4svrll56xW00E9Au7hxw06eoAdqolLXId/D9e5mBK8RslH8KU7DNUfaFqHpRcPyT4CD6uXcjUPKP4N/fDgeSwAmOY6ItRgHtFVzALs5fpLgSSS0QgFkRKp0nasAGyeOvQj+I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742394890; c=relaxed/simple; bh=UVqrr7CHg5bI9QZO7NaevoGBCFDENLEqJUfLClDIZbM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=VGWNdUx1dQrla2YkAUhQ1kTm0oS8bD7g6o/c4Edfm8jZ3rvaVJpuKkfiDkuWgjsoKzmFtJh4inK5G6jcpLLllbYN4TP97+mtX0Wu+nKqRdlY7tTErxRC3k9BCMPJPLNDE7eiBu+7/vn9qcCHI/PF2nbP5WUYIFsY8ULDZSrmYSo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=IIf+BfYJ; 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="IIf+BfYJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 96DA2C4CEE4; Wed, 19 Mar 2025 14:34:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1742394890; bh=UVqrr7CHg5bI9QZO7NaevoGBCFDENLEqJUfLClDIZbM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IIf+BfYJLdJSWUsW3VWyf65R+L3h/KqcY8/I7OM9l9z/pvVo3eE7heBJs1iWsIxMu 9ILJSRcQZmvJy9amcjr3+M1U1TqDp/QTxQU3dyMnzzRraFIFl04cFpl4OtcpZR8bTw +PxOq3ANJ4duLokZeON15Cp0p4oF6Rqdkbz51PaQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, =?UTF-8?q?Marc=20Aur=C3=A8le=20La=20France?= , Rik van Riel , Christoph Hellwig , "Martin K. Petersen" , Sasha Levin Subject: [PATCH 6.13 067/241] scsi: core: Use GFP_NOIO to avoid circular locking dependency Date: Wed, 19 Mar 2025 07:28:57 -0700 Message-ID: <20250319143029.380979635@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250319143027.685727358@linuxfoundation.org> References: <20250319143027.685727358@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-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.13-stable review patch. If anyone has any objections, please let me know. ------------------ From: Rik van Riel [ Upstream commit 5363ee9d110e139584c2d92a0b640bc210588506 ] Filesystems can write to disk from page reclaim with __GFP_FS set. Marc found a case where scsi_realloc_sdev_budget_map() ends up in page reclaim with GFP_KERNEL, where it could try to take filesystem locks again, leading to a deadlock. WARNING: possible circular locking dependency detected 6.13.0 #1 Not tainted ------------------------------------------------------ kswapd0/70 is trying to acquire lock: ffff8881025d5d78 (&q->q_usage_counter(io)){++++}-{0:0}, at: blk_mq_submit_bio+0x461/0x6e0 but task is already holding lock: ffffffff81ef5f40 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0x9f/0x760 The full lockdep splat can be found in Marc's report: https://lkml.org/lkml/2025/1/24/1101 Avoid the potential deadlock by doing the allocation with GFP_NOIO, which prevents both filesystem and block layer recursion. Reported-by: Marc Aurèle La France Signed-off-by: Rik van Riel Link: https://lore.kernel.org/r/20250129104525.0ae8421e@fangorn Reviewed-by: Christoph Hellwig Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin --- drivers/scsi/scsi_scan.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c index 042329b74c6e6..fe08af4dcb67c 100644 --- a/drivers/scsi/scsi_scan.c +++ b/drivers/scsi/scsi_scan.c @@ -245,7 +245,7 @@ static int scsi_realloc_sdev_budget_map(struct scsi_device *sdev, } ret = sbitmap_init_node(&sdev->budget_map, scsi_device_max_queue_depth(sdev), - new_shift, GFP_KERNEL, + new_shift, GFP_NOIO, sdev->request_queue->node, false, true); if (!ret) sbitmap_resize(&sdev->budget_map, depth); -- 2.39.5