linux-kernel - Re: [PATCH 4/8] Drivers: scsi: storvsc: Filter WRITE_SAME

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <1404935792.2184.5.camel@dabdike.int.hansenpartnership.com>
Date:	Wed, 9 Jul 2014 19:56:32 +0000
From:	James Bottomley <jbottomley@...allels.com>
To:	"kys@...rosoft.com" <kys@...rosoft.com>
CC:	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"hch@...radead.org" <hch@...radead.org>,
	"devel@...uxdriverproject.org" <devel@...uxdriverproject.org>,
	"apw@...onical.com" <apw@...onical.com>,
	"stable@...r.kernel.org" <stable@...r.kernel.org>,
	"linux-scsi@...r.kernel.org" <linux-scsi@...r.kernel.org>,
	"ohering@...e.com" <ohering@...e.com>,
	"jasowang@...hat.com" <jasowang@...hat.com>
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@...radead.org]
> > Sent: Wednesday, July 9, 2014 1:43 AM
> > To: KY Srinivasan
> > Cc: linux-kernel@...r.kernel.org; devel@...uxdriverproject.org;
> > ohering@...e.com; jbottomley@...allels.com; jasowang@...hat.com;
> > apw@...onical.com; linux-scsi@...r.kernel.org; stable@...r.kernel.org
> > 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

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/