Re: [PATCH] KVM: x86: inject exceptions produced by x86_decode_insn

2017-11-30 Thread Eduardo Habkost
On Wed, Nov 29, 2017 at 04:42:16PM -0200, Eduardo Habkost wrote: > On Wed, Nov 29, 2017 at 12:44:42PM +0100, Paolo Bonzini wrote: > > On 29/11/2017 12:44, Eduardo Habkost wrote: > > > On Mon, Nov 13, 2017 at 09:32:09AM +0100, Paolo Bonzini wrote: > > >> On 13/11/2017 08:15, Wanpeng Li wrote: > > >>

Re: [PATCH] KVM: x86: inject exceptions produced by x86_decode_insn

2017-11-30 Thread Eduardo Habkost
On Wed, Nov 29, 2017 at 09:10:47PM -0200, Eduardo Habkost wrote: > On Wed, Nov 29, 2017 at 11:47:14PM +0100, Paolo Bonzini wrote: > > On 29/11/2017 19:42, Eduardo Habkost wrote: > > > The reproducer (not a full test case) is quite simple, see patch below. > > > > Great, thanks. I assume that the

Re: [PATCH] KVM: x86: inject exceptions produced by x86_decode_insn

2017-11-30 Thread Paolo Bonzini
On 30/11/2017 10:20, Wanpeng Li wrote: I'm considering trying to write one, but I don't want to duplicate work. >>> No, I haven't written one yet. >> The reproducer (not a full test case) is quite simple, see patch below. > I can also have a look if there is a formal test case. :) FWIW,

Re: [PATCH] KVM: x86: inject exceptions produced by x86_decode_insn

2017-11-30 Thread Wanpeng Li
2017-11-30 2:42 GMT+08:00 Eduardo Habkost : > On Wed, Nov 29, 2017 at 12:44:42PM +0100, Paolo Bonzini wrote: >> On 29/11/2017 12:44, Eduardo Habkost wrote: >> > On Mon, Nov 13, 2017 at 09:32:09AM +0100, Paolo Bonzini wrote: >> >> On 13/11/2017 08:15, Wanpeng Li wrote: >> >>> 2017-11-10 17:49 GMT+08

Re: [PATCH] KVM: x86: inject exceptions produced by x86_decode_insn

2017-11-29 Thread Eduardo Habkost
On Wed, Nov 29, 2017 at 11:47:14PM +0100, Paolo Bonzini wrote: > On 29/11/2017 19:42, Eduardo Habkost wrote: > > The reproducer (not a full test case) is quite simple, see patch below. > > Great, thanks. I assume that the patch doesn't fix it?!? I was so convinced that it was impossible for the

Re: [PATCH] KVM: x86: inject exceptions produced by x86_decode_insn

2017-11-29 Thread Paolo Bonzini
On 29/11/2017 19:42, Eduardo Habkost wrote: > The reproducer (not a full test case) is quite simple, see patch below. Great, thanks. I assume that the patch doesn't fix it?!? Paolo > Now, I've noticed something interesting when running the > reproducer: > > If the test_fetch_failure() call hap

Re: [PATCH] KVM: x86: inject exceptions produced by x86_decode_insn

2017-11-29 Thread Eduardo Habkost
On Wed, Nov 29, 2017 at 12:44:42PM +0100, Paolo Bonzini wrote: > On 29/11/2017 12:44, Eduardo Habkost wrote: > > On Mon, Nov 13, 2017 at 09:32:09AM +0100, Paolo Bonzini wrote: > >> On 13/11/2017 08:15, Wanpeng Li wrote: > >>> 2017-11-10 17:49 GMT+08:00 Paolo Bonzini : > Sometimes, a processor

Re: [PATCH] KVM: x86: inject exceptions produced by x86_decode_insn

2017-11-29 Thread Paolo Bonzini
On 29/11/2017 12:44, Eduardo Habkost wrote: > On Mon, Nov 13, 2017 at 09:32:09AM +0100, Paolo Bonzini wrote: >> On 13/11/2017 08:15, Wanpeng Li wrote: >>> 2017-11-10 17:49 GMT+08:00 Paolo Bonzini : Sometimes, a processor might execute an instruction while another processor is updating the

Re: [PATCH] KVM: x86: inject exceptions produced by x86_decode_insn

2017-11-29 Thread Eduardo Habkost
On Mon, Nov 13, 2017 at 09:32:09AM +0100, Paolo Bonzini wrote: > On 13/11/2017 08:15, Wanpeng Li wrote: > > 2017-11-10 17:49 GMT+08:00 Paolo Bonzini : > >> Sometimes, a processor might execute an instruction while another > >> processor is updating the page tables for that instruction's code page,

Re: [PATCH] KVM: x86: inject exceptions produced by x86_decode_insn

2017-11-16 Thread Radim Krčmář
2017-11-13 09:32+0100, Paolo Bonzini: > On 13/11/2017 08:15, Wanpeng Li wrote: > > 2017-11-10 17:49 GMT+08:00 Paolo Bonzini : > >> Sometimes, a processor might execute an instruction while another > >> processor is updating the page tables for that instruction's code page, > >> but before the TLB s

Re: [PATCH] KVM: x86: inject exceptions produced by x86_decode_insn

2017-11-13 Thread Yanan Fu
- Original Message - > From: "Paolo Bonzini" > To: "Wanpeng Li" > Cc: linux-kernel@vger.kernel.org, "kvm" , > y...@redhat.com, "Eduardo Habkost" > > Sent: Monday, November 13, 2017 4:32:09 PM > Subject: Re: [PATCH] KVM: x86

Re: [PATCH] KVM: x86: inject exceptions produced by x86_decode_insn

2017-11-13 Thread Paolo Bonzini
On 13/11/2017 08:15, Wanpeng Li wrote: > 2017-11-10 17:49 GMT+08:00 Paolo Bonzini : >> Sometimes, a processor might execute an instruction while another >> processor is updating the page tables for that instruction's code page, >> but before the TLB shootdown completes. The interesting case happen

Re: [PATCH] KVM: x86: inject exceptions produced by x86_decode_insn

2017-11-12 Thread Wanpeng Li
2017-11-10 17:49 GMT+08:00 Paolo Bonzini : > Sometimes, a processor might execute an instruction while another > processor is updating the page tables for that instruction's code page, > but before the TLB shootdown completes. The interesting case happens > if the page is in the TLB. > > In genera

Re: [PATCH] KVM: x86: inject exceptions produced by x86_decode_insn

2017-11-10 Thread Radim Krčmář
2017-11-10 10:49+0100, Paolo Bonzini: > Sometimes, a processor might execute an instruction while another > processor is updating the page tables for that instruction's code page, > but before the TLB shootdown completes. The interesting case happens > if the page is in the TLB. > > In general, t