Re: [Xen-devel] [PATCH] x86/HVM: don't retain emulated insn cache when exiting back to guest

2017-12-06 Thread Julien Grall
Hi Andrew, On 12/06/2017 03:08 PM, Andrew Cooper wrote: On 06/12/17 13:04, Julien Grall wrote: Hi Jan, On 12/06/2017 12:58 PM, Jan Beulich wrote: On 06.12.17 at 12:47, wrote: On 12/06/2017 11:45 AM, Jan Beulich wrote: On 06.12.17 at 10:47, wrote: I guess I have been CCed because you woul

Re: [Xen-devel] [PATCH] x86/HVM: don't retain emulated insn cache when exiting back to guest

2017-12-06 Thread Andrew Cooper
On 06/12/17 13:04, Julien Grall wrote: > Hi Jan, > > On 12/06/2017 12:58 PM, Jan Beulich wrote: > On 06.12.17 at 12:47, wrote: >>> On 12/06/2017 11:45 AM, Jan Beulich wrote: >>> On 06.12.17 at 10:47, wrote: > I guess I have been CCed because you would like this patch is > fixing t

Re: [Xen-devel] [PATCH] x86/HVM: don't retain emulated insn cache when exiting back to guest

2017-12-06 Thread Julien Grall
Hi Jan, On 12/06/2017 12:58 PM, Jan Beulich wrote: On 06.12.17 at 12:47, wrote: On 12/06/2017 11:45 AM, Jan Beulich wrote: On 06.12.17 at 10:47, wrote: I guess I have been CCed because you would like this patch is fixing the regression you mentioned on IRC? Yes, but first of all we need t

Re: [Xen-devel] [PATCH] x86/HVM: don't retain emulated insn cache when exiting back to guest

2017-12-06 Thread Jan Beulich
>>> On 06.12.17 at 12:47, wrote: > On 12/06/2017 11:45 AM, Jan Beulich wrote: > On 06.12.17 at 10:47, wrote: >>> I guess I have been CCed because you would like this patch is fixing the >>> regression you mentioned on IRC? >> >> Yes, but first of all we need to see whether the issue goes awa

Re: [Xen-devel] [PATCH] x86/HVM: don't retain emulated insn cache when exiting back to guest

2017-12-06 Thread Julien Grall
On 12/06/2017 11:45 AM, Jan Beulich wrote: On 06.12.17 at 10:47, wrote: I guess I have been CCed because you would like this patch is fixing the regression you mentioned on IRC? Yes, but first of all we need to see whether the issue goes away in master once the patch is in. Would revertin

Re: [Xen-devel] [PATCH] x86/HVM: don't retain emulated insn cache when exiting back to guest

2017-12-06 Thread Jan Beulich
>>> On 06.12.17 at 10:47, wrote: > I guess I have been CCed because you would like this patch is fixing the > regression you mentioned on IRC? Yes, but first of all we need to see whether the issue goes away in master once the patch is in. Jan ___ X

Re: [Xen-devel] [PATCH] x86/HVM: don't retain emulated insn cache when exiting back to guest

2017-12-06 Thread Julien Grall
Hi Jan, I guess I have been CCed because you would like this patch is fixing the regression you mentioned on IRC? Cheers, On 12/05/2017 04:13 PM, Jan Beulich wrote: vio->mmio_retry is being set when a repeated string insn is being split up. In that case we'll exit to the guest, expecting imm

Re: [Xen-devel] [PATCH] x86/HVM: don't retain emulated insn cache when exiting back to guest

2017-12-05 Thread Paul Durrant
> -Original Message- > From: Jan Beulich [mailto:jbeul...@suse.com] > Sent: 05 December 2017 17:19 > To: Paul Durrant > Cc: Julien Grall ; Andrew Cooper > ; xen-devel de...@lists.xenproject.org> > Subject: RE: [PATCH] x86/HVM: don't retain emulated insn cache when > exiting back to guest

Re: [Xen-devel] [PATCH] x86/HVM: don't retain emulated insn cache when exiting back to guest

2017-12-05 Thread Jan Beulich
>>> On 05.12.17 at 17:44, wrote: >> From: Jan Beulich [mailto:jbeul...@suse.com] >> Sent: 05 December 2017 16:14 >> --- a/xen/arch/x86/hvm/emulate.c >> +++ b/xen/arch/x86/hvm/emulate.c >> @@ -2109,20 +2109,22 @@ static int _hvm_emulate_one(struct hvm_e >> >> vio->mmio_retry = 0; >> >> -

Re: [Xen-devel] [PATCH] x86/HVM: don't retain emulated insn cache when exiting back to guest

2017-12-05 Thread Paul Durrant
> -Original Message- > From: Jan Beulich [mailto:jbeul...@suse.com] > Sent: 05 December 2017 16:14 > To: xen-devel > Cc: Julien Grall ; Andrew Cooper > ; Paul Durrant > Subject: [PATCH] x86/HVM: don't retain emulated insn cache when exiting > back to guest > > vio->mmio_retry is being se

[Xen-devel] [PATCH] x86/HVM: don't retain emulated insn cache when exiting back to guest

2017-12-05 Thread Jan Beulich
vio->mmio_retry is being set when a repeated string insn is being split up. In that case we'll exit to the guest, expecting immediate re-entry. Interruptions, however, may be serviced by the guest before re-entry from the repeated string insn. Any emulation needed in the course of handling the inte