From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Jan Beulich" Subject: Re: [PATCH 4/4] x86/PoD: Command line option to prohibit any PoD operations Date: Mon, 02 Nov 2015 07:38:51 -0700 Message-ID: <5637838B02000078000B0CDF@prv-mh.provo.novell.com> References: <1446230022-8349-1-git-send-email-andrew.cooper3@citrix.com> <1446230022-8349-5-git-send-email-andrew.cooper3@citrix.com> <563778D902000078000B0C2C@prv-mh.provo.novell.com> <1446474723.3088.54.camel@citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1446474723.3088.54.camel@citrix.com> Content-Disposition: inline List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Ian Campbell Cc: George Dunlap , Andrew Cooper , Xen-devel List-Id: xen-devel@lists.xenproject.org >>> On 02.11.15 at 15:32, wrote: > On Mon, 2015-11-02 at 06:53 -0700, Jan Beulich wrote: >> > > > On 30.10.15 at 19:33, wrote: >> > --- a/xen/common/memory.c >> > +++ b/xen/common/memory.c >> > @@ -818,6 +818,10 @@ long do_memory_op(unsigned long cmd, >> > XEN_GUEST_HANDLE_PARAM(void) arg) >> > if ( unlikely(start_extent >= reservation.nr_extents) ) >> > return start_extent; >> > >> > + if ( unlikely(!opt_pod_enabled) && >> > + (reservation.mem_flags & XENMEMF_populate_on_demand) ) >> > + return start_extent; >> >> A few lines down we can see that XENMEMF_populate_on_demand >> gets honored only for XENMEM_populate_physmap. Perhaps you >> shouldn't fail the other two which ignore the flag anyway? > > Setting an unexpected flag surely ought to be an error? Admittedly that > particular ship may have sailed WRT this public ABI. Without that latter aspect I would certainly answer the question with "Yes". Jan