From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Cooper Subject: Re: =?utf-8?q?=5BPATCH_v4_RFC_2/6=5D_x86/MSI-X=3A_track_h?= =?utf-8?q?ost_and_guest_mask=E2=80=91all_requests_separately?= Date: Thu, 25 Jun 2015 15:25:23 +0100 Message-ID: <558C0F53.4040501@citrix.com> References: <558839ED02000078000879FE@mail.emea.novell.com> <55883C240200007800087A24@mail.emea.novell.com> <558AE5A3.3080202@citrix.com> <558BD17E0200007800089594@mail.emea.novell.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta14.messagelabs.com ([193.109.254.103]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1Z885s-0008PX-PX for xen-devel@lists.xenproject.org; Thu, 25 Jun 2015 14:25:32 +0000 In-Reply-To: <558BD17E0200007800089594@mail.emea.novell.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Jan Beulich Cc: xen-devel , Keir Fraser List-Id: xen-devel@lists.xenproject.org On 25/06/15 09:01, Jan Beulich wrote: >>>> On 24.06.15 at 19:15, wrote: >> On 22/06/15 15:47, Jan Beulich wrote: >>> Host uses of the bits will be added subsequently, and must not be >>> overridden by guests (including Dom0, namely when acting on behalf of >>> a guest). >>> >>> Signed-off-by: Jan Beulich >>> >>> --- a/xen/arch/x86/msi.c >>> +++ b/xen/arch/x86/msi.c >>> @@ -846,6 +846,12 @@ static int msix_capability_init(struct p >>> >>> if ( !msix->used_entries ) >>> { >>> + msix->host_maskall = 0; >>> + if ( !msix->guest_maskall ) >>> + control &= ~PCI_MSIX_FLAGS_MASKALL; >>> + else >>> + control |= PCI_MSIX_FLAGS_MASKALL; >> Is the guest (or hardware) in a position to influence guest_maskall at >> this point? I am not sure that it is. > Of course - via the cfg write intercept (i.e. the hunk immediately > following this one). So it is. I had got the call chronology confused. Reviewed-by: Andrew Cooper (although perhaps better to wait until we understand Sanders MSI masking problem). ~Andrew