Re: [PATCH] scsi: core: Call blk_mq_free_tag_set() earlier

[Ming Lei <ming.lei@redhat.com>]

Hi Bart,

I'd rather to understand the issue first.

On Wed, Jun 29, 2022 at 02:49:27PM -0700, Bart Van Assche wrote:
> On 6/28/22 18:17, Ming Lei wrote:
> > On Tue, Jun 28, 2022 at 10:56:12AM -0700, Bart Van Assche wrote:
> > > There are two .exit_cmd_priv implementations. Both implementations use the
> > > SCSI host pointer. Make sure that the SCSI host pointer is valid when
> > > .exit_cmd_priv is called by moving the .exit_cmd_priv calls from
> > > scsi_device_dev_release() to scsi_forget_host(). Moving

.exit_cmd_priv is actually called from scsi_host_dev_release() instead
of scsi_device_dev_release(). Both scsi host pointer and host->shost_data is
still valid when calling .exit_cmd_priv via scsi_mq_destroy_tags().

Previously I fixed[1] one similar issue, and that is caused by early module
unloading, and anywhere host->hostt is referred, the scsi driver module
should be prevented from being unloaded.


[1] f2b85040acec scsi: core: Put LLD module refcnt after SCSI device is released


Thanks,
Ming