From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris J Arges Subject: Re: [PATCH] mptfusion: enable no_write_same in scsi_host_template Date: Mon, 22 Sep 2014 13:17:01 -0500 Message-ID: <5420679D.3070406@canonical.com> References: <1411408690-4766-1-git-send-email-chris.j.arges@canonical.com> <20140922180220.GA10166@infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20140922180220.GA10166@infradead.org> Sender: linux-kernel-owner@vger.kernel.org To: Christoph Hellwig Cc: linux-scsi@vget.kernel.org, bruce.lucas@mongodb.com, Nagalakshmi Nandigama , Praveen Krishnamoorthy , Sreekanth Reddy , Abhijit Mahajan , MPT-FusionLinux.pdl@avagotech.com, linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-scsi@vger.kernel.org On 09/22/2014 01:02 PM, Christoph Hellwig wrote: > On Mon, Sep 22, 2014 at 12:56:59PM -0500, Chris J Arges wrote: >> When using a virtual SCSI disk in a VMWare VM if blkdev_issue_zeroout is used >> data can be improperly zeroed out using the mptfusion driver. This patch >> disables write_same for this driver which ensures that manual zeroing out >> is used instead. > > Does this affet real hardware or is it a VMware bug? If it's just the > latter we should simply blacklist VMware. > I've only been able to reproduce this on VMWare. There is a pretty straightforward reproducer in the BugLink if there is any interest in verifying on hardware. How would you recommending blacklisting only VMWare guests in this case? Thanks, --chris j arges