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Subject: Re: [resend v1 5/5] drivers/scsi/sd.c: Convert to use
 disk_set_capacity
From:   "Ewan D. Milne" <emilne@redhat.com>
To:     "Martin K. Petersen" <martin.petersen@oracle.com>
Cc:     James Bottomley <jejb@linux.ibm.com>, axboe@kernel.dk,
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Date:   Wed, 08 Jan 2020 16:27:55 -0500
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On Tue, 2020-01-07 at 21:59 -0500, Martin K. Petersen wrote:
> Ewan,
> 
> > Yes, there are some storage arrays that refuse a READ CAPACITY
> > command in certain ALUA states so you can't get the new capacity
> > anyway.
> 
> Yep. And some devices will temporarily return a capacity of
> 0xFFFFFFFF... If we were to trigger a filesystem resize, the results
> would be disastrous.
> 
> > It might be nice to improve this, though, there are some cases now
> > where we set the capacity to zero when we revalidate and can't get the
> > value.
> 
> If you have a test case, let's fix it.
> 

This happens with NVMe fabric devices, I thought.  I'll check.