From: Christoph Hellwig <hch@infradead.org>
To: Bart Van Assche <bvanassche@acm.org>
Cc: Jason Gunthorpe <jgg@ziepe.ca>,
Doug Ledford <dledford@redhat.com>,
linux-rdma@vger.kernel.org,
Sergey Gorenko <sergeygo@mellanox.com>,
Max Gurtovoy <maxg@mellanox.com>,
Laurence Oberman <loberman@redhat.com>,
stable@vger.kernel.org, linux-scsi@vger.kernel.org
Subject: Re: [PATCH 1/2] RDMA/srp: Avoid calling mutex_lock() from inside scsi_queue_rq()
Date: Sat, 19 Jan 2019 02:03:04 -0800 [thread overview]
Message-ID: <20190119100304.GB24246@infradead.org> (raw)
In-Reply-To: <20190117002717.84686-2-bvanassche@acm.org>
On Wed, Jan 16, 2019 at 04:27:16PM -0800, Bart Van Assche wrote:
> In scsi-mq mode it is not allowed to sleep inside srp_queuecommand()
> since the flag BLK_MQ_F_BLOCKING has not been set. Since setting the
> request queue flag BLK_MQ_F_BLOCKING would slow down the hot path, make
> srp_queuecommand() skip the mutex_lock() and mutex_unlock() calls when
> called from inside scsi_queue_rq() from the SCSI EH thread.
>
> This patch avoids that the following appears in the kernel log:
I think we need to get rid of the taking a sleeping lock in
->queuecomand entirely. These checks are way to fragile.
next prev parent reply other threads:[~2019-01-19 10:03 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20190117002717.84686-1-bvanassche@acm.org>
2019-01-17 0:27 ` [PATCH 1/2] RDMA/srp: Avoid calling mutex_lock() from inside scsi_queue_rq() Bart Van Assche
2019-01-19 10:03 ` Christoph Hellwig [this message]
2019-01-21 21:21 ` Bart Van Assche
2019-01-17 0:27 ` [PATCH 2/2] RDMA/srp: Rework SCSI device reset handling Bart Van Assche
2019-01-19 10:04 ` Christoph Hellwig
2019-01-21 21:08 ` Bart Van Assche
[not found] ` <20190122155559.D1DD9217D6@mail.kernel.org>
2019-01-22 16:04 ` Bart Van Assche
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