From: Greg KH <gregkh@linuxfoundation.org>
To: Zheng Qixing <zhengqixing@huaweicloud.com>
Cc: cve@kernel.org, linux-cve-announce@vger.kernel.org,
linux-kernel@vger.kernel.org, yukuai@fnnas.com,
ming.lei@redhat.com, Nilay Shroff <nilay@linux.ibm.com>,
"zhangyi (F)" <yi.zhang@huawei.com>,
yangerkun <yangerkun@huawei.com>, Hou Tao <houtao1@huawei.com>
Subject: Re: CVE-2025-40146: blk-mq: fix potential deadlock while nr_requests grown
Date: Thu, 27 Nov 2025 14:39:55 +0100 [thread overview]
Message-ID: <2025112730-semicolon-verse-164a@gregkh> (raw)
In-Reply-To: <15fb6eed-e107-4ef7-a569-3328a02e2c39@huaweicloud.com>
On Thu, Nov 27, 2025 at 09:22:42PM +0800, Zheng Qixing wrote:
> Hi,
>
> Commit b86433721f46 ("blk-mq: fix potential deadlock while nr_requests
> grown") aims to avoid a deadlock issue when the queue is frozen and memory
> reclaim is triggered.
>
> However, the sysfs nr_requests update path is already under a
> memalloc_noio_save() region while the queue is frozen (via
> blk_mq_freeze_queue()).
Did the lockdep splat in
https://lore.kernel.org/all/0659ea8d-a463-47c8-9180-43c719e106eb@linux.ibm.com/
not describe the issue here that the commit is attempting to solve?
thanks,
greg k-h
next prev parent reply other threads:[~2025-11-27 13:40 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <2025111256-CVE-2025-40146-b919@gregkh>
2025-11-27 13:22 ` CVE-2025-40146: blk-mq: fix potential deadlock while nr_requests grown Zheng Qixing
2025-11-27 13:39 ` Greg KH [this message]
2025-11-28 1:15 ` Zheng Qixing
2025-11-28 5:20 ` Nilay Shroff
2025-11-28 6:33 ` yangerkun
2025-11-28 7:15 ` Nilay Shroff
2025-11-28 9:44 ` Zheng Qixing
2025-11-29 3:52 ` Zheng Qixing
2025-11-29 4:01 ` Zheng Qixing
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