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From: Ming Lei <ming.lei@redhat.com>
To: Yi Zhang <yi.zhang@redhat.com>
Cc: linux-block <linux-block@vger.kernel.org>,
	"open list:NVM EXPRESS DRIVER" <linux-nvme@lists.infradead.org>,
	Shinichiro Kawasaki <shinichiro.kawasaki@wdc.com>,
	Christoph Hellwig <hch@lst.de>, Sagi Grimberg <sagi@grimberg.me>,
	Chaitanya Kulkarni <chaitanyak@nvidia.com>
Subject: Re: [bug report] nvme-tcp poll queue causes busy loop and 100% CPU in nvme_tcp_poll() on the latest linux-block/for-next
Date: Wed, 21 Jan 2026 16:53:10 +0800	[thread overview]
Message-ID: <aXCT9sFChMdhwNYw@fedora> (raw)
In-Reply-To: <CAHj4cs9JJu+dDZqAvCd1qPM1CZuV-_b-AHxXpU-vJrGHHO-ExA@mail.gmail.com>

On Wed, Jan 21, 2026 at 10:50:00AM +0800, Yi Zhang wrote:
> Hi
> 
> This issue was observed on the latest linux-block/for-next during CKI
> test, where enabling the poll queues leads to a tight busy polling
> loop and 100% CPU usage during "nvme connect".
> It seems was introduced from v6.19-rc1 and cannot reproduced on v6.18.
> I will try to bisect it.

It may be related with f22ecf9c14c1 ("blk-mq: delete task running check
in blk_hctx_poll()").

I guess it only happens when `nvme connect` takes a bit long time, not sure if
it can be reproduced 100%.


Thanks,
Ming


  parent reply	other threads:[~2026-01-21  8:53 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-01-21  2:50 [bug report] nvme-tcp poll queue causes busy loop and 100% CPU in nvme_tcp_poll() on the latest linux-block/for-next Yi Zhang
2026-01-21  8:25 ` Christoph Hellwig
2026-01-21  8:53 ` Ming Lei [this message]
2026-01-21  9:03   ` Yi Zhang
     [not found]     ` <CAHj4cs_BWMOsn7MwNc=YNsmN=TM_r8WK_o2qa3DedqA4rtHefw@mail.gmail.com>
2026-01-22  3:48       ` Ming Lei

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