From mboxrd@z Thu Jan 1 00:00:00 1970 From: George Dunlap Subject: Re: [PATCH] QEMU(upstream): Disable xen's use of O_DIRECT by default as it results in crashes. Date: Fri, 8 Mar 2013 11:18:45 +0000 Message-ID: <5139C915.5080309@eu.citrix.com> References: <1362653247-32551-1-git-send-email-alex@alex.org.uk> <28ABF94D2CD0737DF699D761@nimrod.local> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <28ABF94D2CD0737DF699D761@nimrod.local> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Alex Bligh Cc: Ian Campbell , Stefano Stabellini , Konrad Rzeszutek Wilk , Ian Jackson , xen-devel , Jan Beulich List-Id: xen-devel@lists.xenproject.org On 08/03/13 10:50, Alex Bligh wrote: > > --On 8 March 2013 10:35:43 +0000 George Dunlap wrote: > >> If you can verify that it's always safe to use qemu without O_DIRECT >> (or that it's not any safer to use it), then you should just remove >> it; no point in having options which have no practical effect. But in >> that case you should make sure to mention in the commit message why >> O_DIRECT isn't actually needed. > How about me adding the following: > > This brings PV devices in line with emulated devices. Removing O_DIRECT > is safe as barrier operations are now correctly passed through. That sounds good to me -- thanks, Alex. -George