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 1D6BD30FF2E; Mon, 13 Oct 2025 15:06:21 +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=1760367981; cv=none; b=A5nn12I3aSpchjljLVBJHAseJ2bi4dLfon7XM/DQKhkPf48N2MJMnOCNsQcWJ0sME4QvPpgGdVnxr1qC1yHS2wJ1DPacHohiV1h6FPbcWD6MwRcMDagXrceolXZR9qy3tDyyuM5h5aAp7D20ceJd17q1pwngE+jfY2xSYBRiw7Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760367981; c=relaxed/simple; bh=+GkBuIUVw9XziaXgu7LwyQ03f2sIS5nuzQRnJr/8vPc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=I8qPhfQzrvb2tMYUEhNXxIJ6Vm3uG/YppbfcViR6GiTXBsVoyojJ6ll/JicFGr1b1rk9J1fnj9GHeuTfJBfS6V81GbG4+INt8HCvXPBQ4ZzPOF/vTFRRD6DoClr25AxY91ypDJ9gikSBVm9HYM+/y1ZtN1rplNX1Njru5VXtnjA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=M1z87T0d; 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="M1z87T0d" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 98F61C4CEFE; Mon, 13 Oct 2025 15:06:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1760367981; bh=+GkBuIUVw9XziaXgu7LwyQ03f2sIS5nuzQRnJr/8vPc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=M1z87T0dR9BkKI4ea9t+XFccGJzGU5l66XtVqVM5KkmgBmEMZEpCTR4MWqdsB6t7E ZKlh10Xekppfyv1R/ahv4Cg71rBDc0KFM8wbtXlrId9tuwcIWlSeeI6soMMX0kCE74 XcRlA/LBVKrVzpLJGOriKupyjwvryg6ZDlUBHv1M= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Zheng Qixing , Mikulas Patocka Subject: [PATCH 6.6 177/196] dm: fix queue start/stop imbalance under suspend/load/resume races Date: Mon, 13 Oct 2025 16:46:08 +0200 Message-ID: <20251013144321.712179138@linuxfoundation.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20251013144315.184275491@linuxfoundation.org> References: <20251013144315.184275491@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Zheng Qixing commit 7f597c2cdb9d3263a6fce07c4fc0a9eaa8e8fc43 upstream. When suspend and load run concurrently, before q->mq_ops is set in blk_mq_init_allocated_queue(), __dm_suspend() skip dm_stop_queue(). As a result, the queue's quiesce depth is not incremented. Later, once table load has finished and __dm_resume() runs, which triggers q->quiesce_depth ==0 warning in blk_mq_unquiesce_queue(): Call Trace: dm_start_queue+0x16/0x20 [dm_mod] __dm_resume+0xac/0xb0 [dm_mod] dm_resume+0x12d/0x150 [dm_mod] do_resume+0x2c2/0x420 [dm_mod] dev_suspend+0x30/0x130 [dm_mod] ctl_ioctl+0x402/0x570 [dm_mod] dm_ctl_ioctl+0x23/0x30 [dm_mod] Fix this by explicitly tracking whether the request queue was stopped in __dm_suspend() via a new DMF_QUEUE_STOPPED flag. Only call dm_start_queue() in __dm_resume() if the queue was actually stopped. Fixes: e70feb8b3e68 ("blk-mq: support concurrent queue quiesce/unquiesce") Cc: stable@vger.kernel.org Signed-off-by: Zheng Qixing Signed-off-by: Mikulas Patocka Signed-off-by: Greg Kroah-Hartman --- drivers/md/dm-core.h | 1 + drivers/md/dm.c | 8 +++++--- 2 files changed, 6 insertions(+), 3 deletions(-) --- a/drivers/md/dm-core.h +++ b/drivers/md/dm-core.h @@ -161,6 +161,7 @@ struct mapped_device { #define DMF_SUSPENDED_INTERNALLY 7 #define DMF_POST_SUSPENDING 8 #define DMF_EMULATE_ZONE_APPEND 9 +#define DMF_QUEUE_STOPPED 10 void disable_discard(struct mapped_device *md); void disable_write_zeroes(struct mapped_device *md); --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -2740,8 +2740,10 @@ static int __dm_suspend(struct mapped_de * Stop md->queue before flushing md->wq in case request-based * dm defers requests to md->wq from md->queue. */ - if (dm_request_based(md)) + if (dm_request_based(md)) { dm_stop_queue(md->queue); + set_bit(DMF_QUEUE_STOPPED, &md->flags); + } flush_workqueue(md->wq); @@ -2763,7 +2765,7 @@ static int __dm_suspend(struct mapped_de if (r < 0) { dm_queue_flush(md); - if (dm_request_based(md)) + if (test_and_clear_bit(DMF_QUEUE_STOPPED, &md->flags)) dm_start_queue(md->queue); unlock_fs(md); @@ -2847,7 +2849,7 @@ static int __dm_resume(struct mapped_dev * so that mapping of targets can work correctly. * Request-based dm is queueing the deferred I/Os in its request_queue. */ - if (dm_request_based(md)) + if (test_and_clear_bit(DMF_QUEUE_STOPPED, &md->flags)) dm_start_queue(md->queue); unlock_fs(md);