I ve seen that I ve accidentally dropped the list from the email..
So for fstps for the 32bit - how does this patch look?
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index a252081d..83b0fd2 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -1139,6 +1139,27 @@ static int em_fninit(struct x86_emulate_ctxt *ctxt)
return X86EMUL_CONTINUE;
}
+static int em_fld(struct x86_emulate_ctxt *ctxt)
+{
+ ctxt->ops->get_fpu(ctxt);
+ asm volatile("fld %0": "+m"(ctxt->src.val));
+ ctxt->ops->put_fpu(ctxt);
+
+ return X86EMUL_CONTINUE;
+}
+
+static int em_fstp(struct x86_emulate_ctxt *ctxt)
+{
+ u32 fcw;
+
+ ctxt->ops->get_fpu(ctxt);
+ asm volatile("fstp %0": "+m"(fcw));
+ ctxt->ops->put_fpu(ctxt);
+
+ ctxt->dst.val = fcw;
+ return X86EMUL_CONTINUE;
+}
+
static int em_fnstcw(struct x86_emulate_ctxt *ctxt)
{
u16 fcw;
@@ -4438,7 +4459,7 @@ static const struct gprefix pfx_0f_e7 = {
};
static const struct escape escape_d9 = { {
- N, N, N, N, N, N, N, I(DstMem16 | Mov, em_fnstcw),
+ I(SrcMem | Stack, em_fld), N, N, I(DstMem | Mov | Stack,
em_fstp), N, N, N, I(DstMem16 | Mov, em_fnstcw),
}, {
/* 0xC0 - 0xC7 */
N, N, N, N, N, N, N, N,
Miltiadis Hatzimihail
On Tue, May 16, 2017 at 9:09 AM, Miltiadis Hatzimihail <
hatzimil...@gmail.com> wrote:
> How does this patch look to you?
>
> --- a/arch/x86/kvm/emulate.c
>
> +++ b/arch/x86/kvm/emulate.c
>
> @@ -1139,6 +1139,27 @@ static int em_fninit(struct x86_emulate_ctxt *ctxt)
>
> return X86EMUL_CONTINUE;
>
> }
>
>
>
> +static int em_fld(struct x86_emulate_ctxt *ctxt)
>
> +{
>
> + ctxt->ops->get_fpu(ctxt);
>
> + asm volatile("fld %0": "+m"(ctxt->src.val));
>
> + ctxt->ops->put_fpu(ctxt);
>
> +
>
> + return X86EMUL_CONTINUE;
>
> +}
>
> +
>
> +static int em_fstp(struct x86_emulate_ctxt *ctxt)
>
> +{
>
> + u32 fcw;
>
> +
>
> + ctxt->ops->get_fpu(ctxt);
>
> + asm volatile("fstp %0": "+m"(fcw));
>
> + ctxt->ops->put_fpu(ctxt);
>
> +
>
> + ctxt->dst.val = fcw;
>
> + return X86EMUL_CONTINUE;
>
> +}
>
> +
>
> static int em_fnstcw(struct x86_emulate_ctxt *ctxt)
>
> {
>
> u16 fcw;
>
> @@ -4438,7 +4459,7 @@ static const struct gprefix pfx_0f_e7 = {
>
> };
>
>
>
> static const struct escape escape_d9 = { {
>
> - N, N, N, N, N, N, N, I(DstMem16 | Mov, em_fnstcw),
>
> + I(SrcMem | Stack, em_fld), N, N, I(DstMem | Mov | Stack,
> em_fstp), N, N, N, I(DstMem16 | Mov, em_fnstcw),
>
> }, {
>
> /* 0xC0 - 0xC7 */
>
> N, N, N, N, N, N, N, N,
>
>
> Miltiadis Hatzimihail
>
>
> On Mon, May 15, 2017 at 8:58 AM, Paolo Bonzini <pbonz...@redhat.com>
> wrote:
>
>>
>>
>> On 15/05/2017 08:42, Miltiadis Hatzimihail wrote:
>> > Thanks - is it just a matter of adjusting your old patch for this
>> > command? (I looked up the opcode and it was dd or d9 I think).
>>
>> The encoding of fstps is a bit different because it's an x87
>> instruction, but the idea is the same.
>>
>> Paolo
>> >
>> > Miltiadis Hatzimihail
>> >
>> >
>> > On Fri, May 12, 2017 at 1:00 PM, Paolo Bonzini <pbonz...@redhat.com
>> > <mailto:pbonz...@redhat.com>> wrote:
>> >
>> >
>> >
>> > On 12/05/2017 09:26, Miltiadis Hatzimihail wrote:
>> > > I ve tried the same today using a 32-bit Guest OS and the illegal
>> > > instruction this time is
>> > >
>> > > fstps %(ecx)
>> > >
>> > > Is it a similar case to the movss one? (the previous Guest I was
>> using
>> > > was 64 bit).
>> >
>> > Yes, it is.
>> >
>> > Paolo
>> >
>> > > Also, I had to start QEMU using the following command line
>> options:
>> > >
>> > > qemu -cpu host,-sse2
>> > >
>> > > because one my programs was giving me an illegal instruction
>> based on
>> > > the above and it worked by disabling it.
>> > >
>> > > Regards
>> > > Milton
>> > >
>> > > On Thu, May 11, 2017 at 2:12 PM, Miltiadis Hatzimihail
>> > > <hatzimil...@gmail.com <mailto:hatzimil...@gmail.com>
>> > <mailto:hatzimil...@gmail.com <mailto:hatzimil...@gmail.com>>>
>> wrote:
>> > >
>> > > Ok many thanks for your help.
>> > >
>> > > Milton
>> > >
>> > > On Thu, May 11, 2017 at 2:11 PM, Paolo Bonzini <
>> pbonz...@redhat.com <mailto:pbonz...@redhat.com>
>> > > <mailto:pbonz...@redhat.com <mailto:pbonz...@redhat.com>>>
>> wrote:
>> > >
>> > >
>> > >
>> > > On 11/05/2017 14:47, Miltiadis Hatzimihail wrote:
>> > > > That's great thanks for the clarification.
>> > > >
>> > > > Is this patch going to make it to the mainline at some
>> > point?
>> > >
>> > > Not exactly as is, because it has a small defect (it
>> > always reads 16
>> > > bytes from memory), but something like that will.
>> > >
>> > > Paolo
>> > >
>> > >
>> > >
>> >
>> >
>>
>
>
