Re: raid 5 creation fails on usb3 connected drives kernel 4.4.x, 4.5

[James Bottomley <James.Bottomley@HansenPartnership.com>]

On Sat, 2016-04-16 at 09:08 -0700, Greg KH wrote:
> On Sat, Apr 09, 2016 at 08:18:26PM +1000, Brian Chadwick wrote:
> > On 09/04/16 00:24, Greg KH wrote:
> > > On Fri, Apr 08, 2016 at 07:37:12PM +1000, Brian Chadwick wrote:
> > > > On 08/04/16 01:59, Greg KH wrote:
> > > > > On Fri, Apr 08, 2016 at 01:34:51AM +1000, Brian Chadwick
> > > > > wrote:
> > > > > > On 08/04/16 00:44, Greg KH wrote:
> > > > > > > On Thu, Apr 07, 2016 at 03:04:55PM +1000, Brian Chadwick
> > > > > > > wrote:
> > > > > > > > On 06/04/16 19:53, Greg KH wrote:
> > > > > > > > > On Tue, Apr 05, 2016 at 06:42:51PM +1000, Brian
> > > > > > > > > Chadwick wrote:
> > > > > > > > > > SETUP:
> > > > > > > > > > 
> > > > > > > > > > i7 16GB Computer.
> > > > > > > > > > 
> > > > > > > > > > 1 x PCI-x USB3 adaptor card (i think uses xhci
> > > > > > > > > > -hcd)04:00.0 USB controller:
> > > > > > > > > > Renesas Technology Corp. uPD720202 USB 3.0 Host
> > > > > > > > > > Controller (rev 02)
> > > > > > > > > >         Kernel driver in use: xhci_hcd
> > > > > > > > > > 
> > > > > > > > > > 2 x USB3 to dual SATA HDD docks. uses JMicron
> > > > > > > > > > JMS56x Series controllers,
> > > > > > > > > > uses uas.ko kernel module
> > > > > > > > > > Bus 004 Device 002: ID 152d:9561 JMicron Technology
> > > > > > > > > > Corp. / JMicron USA
> > > > > > > > > > Technology Corp.
> > > > > > > > > > Bus 004 Device 003: ID 152d:9561 JMicron Technology
> > > > > > > > > > Corp. / JMicron USA
> > > > > > > > > > Technology Corp.
> > > > > > > > > > 
> > > > > > > > > > 3 x Western Digital 320GB 3.5" SATA drives
> > > > > > > > > > 
> > > > > > > > > > USE:
> > > > > > > > > > 
> > > > > > > > > > RAID 5
> > > > > > > > > > 
> > > > > > > > > > KERNEL:
> > > > > > > > > > 4.3.5
> > > > > > > > > > 
> > > > > > > > > > System works perfectly as expected.
> > > > > > > > > > 
> > > > > > > > > > 
> > > > > > > > > > Change to kernel 4.4.x or 4.5 and RAID 5 doesnt
> > > > > > > > > > work. I am not sure whether
> > > > > > > > > > its actually RAID 5 at fault or if its the USB
> > > > > > > > > > Attached SCSI driver uas.ko,
> > > > > > > > > > or maybe the host driver xhci-hcd.
> > > > > > > > > Can you run 'git bisect' to try to track down the
> > > > > > > > > offending commit?
> 
> <instructions about git-bisect snipped>
> 
> > Hi, well to my surprise git bisect has come up with a commit about
> > which I
> > had no inkling. I may have to go to another mailing list it doesnt
> > look like
> > a usb problem.
> > 
> > This is the final output of 'git bisect view' :
> > 
> > 
> > commit 64d513ac31bd02a3c9b69ef04444f36c196f9a9d
> > Author: Christoph Hellwig <hch@lst.de>
> > Date:   Thu Oct 8 09:28:04 2015 +0100
> > 
> >     scsi: use host wide tags by default
> > 
> >     This patch changes the !blk-mq path to the same defaults as the
> > blk-mq
> >     I/O path by always enabling block tagging, and always using
> > host wide
> >     tags.  We've had blk-mq available for a few releases so bugs
> > with
> >     this mode should have been ironed out, and this ensures we get
> > better
> >     coverage of over tagging setup over different configs.
> > 
> >     Signed-off-by: Christoph Hellwig <hch@lst.de>
> >     Acked-by: Jens Axboe <axboe@kernel.dk>
> >     Reviewed-by: Hannes Reinecke <hare@suse.de>
> >     Signed-off-by: James Bottomley <JBottomley@Odin.com>
> > 
> > 
> > 
> > Thank you for your help in narrowing this down, and in educating me
> > about
> > git bisect (its a neat tool) ... I await your advice as how to
> > proceed from
> > here.
> 
> Sorry for the delay, nice work tracking down the problem.
> 
> Christoph, any ideas?  This patch is breaking this user's system as
> described above.  Is there a more recent fix for this, or did
> something
> forget to get changed in the large patch you did here?

If this is UAS connected devices, then this is likely the fix:

http://marc.info/?l=linux-scsi&m=146045685829613

James