From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mike Snitzer <snitzer@redhat.com>
Subject: Re: dm + blk-mq soft lockup complaint
Date: Thu, 15 Jan 2015 10:43:43 -0500
Message-ID: <20150115154343.GA11859@redhat.com>
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To: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Keith Busch <keith.busch@intel.com>, Jens Axboe <axboe@kernel.dk>, Christoph Hellwig <hch@infradead.org>, device-mapper development <dm-devel@redhat.com>, Jun'ichi Nomura <j-nomura@ce.jp.nec.com>, linux-scsi@vger.kernel.org
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On Thu, Jan 15 2015 at  3:11am -0500,
Bart Van Assche <bart.vanassche@sandisk.com> wrote:

> On 01/14/15 20:00, Mike Snitzer wrote:
> > IB aside, I haven't been following along close enough on scsi-mq
> > developments, but does a regular iscsi initiator have support for
> > scsi-mq?  I'd like to validate scsi-mq devices with the dm-mpath
> > changes.
> 
> Hello Mike,
> 
> scsi-mq support for the iSCSI initiator is being considered but has not
> yet been implemented. For more information, see also Sagi Grimberg,
> [LSF/MM TOPIC] iSCSI MQ adoption via MCS discussion, linux-scsi mailing
> list, January 7, 2015 (http://thread.gmane.org/gmane.linux.scsi/98199).

OK, thanks.

FYI, I just used your fio test against an mpath device that is using 4
virtio-scsi devices with blk-mq enabled and all worked fine.

How easily could you reproduce your SRP hang?  Did it happen every run
or did it take multiple runs to see it?