> -----Original Message----- > From: James Bottomley [mailto:jbottomley@xxxxxxxxxxxxx] > Sent: Wednesday, July 9, 2014 12:57 PM > To: KY Srinivasan > Cc: linux-kernel@xxxxxxxxxxxxxxx; hch@xxxxxxxxxxxxx; > devel@xxxxxxxxxxxxxxxxxxxxxx; apw@xxxxxxxxxxxxx; stable@xxxxxxxxxxxxxxx; > linux-scsi@xxxxxxxxxxxxxxx; ohering@xxxxxxxx; jasowang@xxxxxxxxxx > Subject: Re: [PATCH 4/8] Drivers: scsi: storvsc: Filter WRITE_SAME_16 > > On Wed, 2014-07-09 at 19:52 +0000, KY Srinivasan wrote: > > > > > -----Original Message----- > > > From: Christoph Hellwig [mailto:hch@xxxxxxxxxxxxx] > > > Sent: Wednesday, July 9, 2014 1:43 AM > > > To: KY Srinivasan > > > Cc: linux-kernel@xxxxxxxxxxxxxxx; devel@xxxxxxxxxxxxxxxxxxxxxx; > > > ohering@xxxxxxxx; jbottomley@xxxxxxxxxxxxx; jasowang@xxxxxxxxxx; > > > apw@xxxxxxxxxxxxx; linux-scsi@xxxxxxxxxxxxxxx; > > > stable@xxxxxxxxxxxxxxx > > > Subject: Re: [PATCH 4/8] Drivers: scsi: storvsc: Filter > > > WRITE_SAME_16 > > > > > > On Tue, Jul 08, 2014 at 05:46:48PM -0700, K. Y. Srinivasan wrote: > > > > Host does not handle WRITE_SAME_16; filter this command out. This > > > > patch is required to handle large devices (greater than 2 TB disks). > > > > > > Storvsc already sets the no_write_same flag, where is the command > > > coming from? > > > > In spite of this flag, I see WRITE_SAME_16 being issued when I format > > a device bigger than 2 TB; I tried both xfs and ext4. Windows hosts > > currently do not handle unsupported commands correctly - The > > information returned is not sufficient to effect recovery in the Linux guest. > While this may be addressed in future hosts, this patch fixes the problem. > > What Christoph means is that this looks like a bug somewhere in SCSI itself. > That means we need to find it and kill it, not add workarounds to every driver > that sets no_write_same ... James, I will try to isolate this issue in the SCSI stack. If it is ok with you guys, I would still want to filter WRITE_SAME_16 (as we currently do WRITE_SAME) in our driver since this would address the problem for a large number of customers on our platform. Regards, K. Y -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html