| Message ID | 20201103120400.240882-1-david.edmondson@oracle.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: x86: clflushopt should be treated as a no-op by emulation | expand |
On 11/3/20 12:04 PM, David Edmondson wrote: > The instruction emulator ignores clflush instructions, yet fails to > support clflushopt. Treat both similarly. > > Fixes: 13e457e0eebf ("KVM: x86: Emulator does not decode clflush well") > Signed-off-by: David Edmondson <david.edmondson@oracle.com> FWIW, Reviewed-by: Joao Martins <joao.m.martins@oracle.com> > --- > arch/x86/kvm/emulate.c | 8 +++++++- > 1 file changed, 7 insertions(+), 1 deletion(-) > > diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c > index 0d917eb70319..56cae1ff9e3f 100644 > --- a/arch/x86/kvm/emulate.c > +++ b/arch/x86/kvm/emulate.c > @@ -4046,6 +4046,12 @@ static int em_clflush(struct x86_emulate_ctxt *ctxt) > return X86EMUL_CONTINUE; > } > > +static int em_clflushopt(struct x86_emulate_ctxt *ctxt) > +{ > + /* emulating clflushopt regardless of cpuid */ > + return X86EMUL_CONTINUE; > +} > + > static int em_movsxd(struct x86_emulate_ctxt *ctxt) > { > ctxt->dst.val = (s32) ctxt->src.val; > @@ -4585,7 +4591,7 @@ static const struct opcode group11[] = { > }; > > static const struct gprefix pfx_0f_ae_7 = { > - I(SrcMem | ByteOp, em_clflush), N, N, N, > + I(SrcMem | ByteOp, em_clflush), I(SrcMem | ByteOp, em_clflushopt), N, N, > }; > > static const struct group_dual group15 = { { >
On 03/11/20 13:04, David Edmondson wrote: > The instruction emulator ignores clflush instructions, yet fails to > support clflushopt. Treat both similarly. > > Fixes: 13e457e0eebf ("KVM: x86: Emulator does not decode clflush well") > Signed-off-by: David Edmondson <david.edmondson@oracle.com> > --- > arch/x86/kvm/emulate.c | 8 +++++++- > 1 file changed, 7 insertions(+), 1 deletion(-) > > diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c > index 0d917eb70319..56cae1ff9e3f 100644 > --- a/arch/x86/kvm/emulate.c > +++ b/arch/x86/kvm/emulate.c > @@ -4046,6 +4046,12 @@ static int em_clflush(struct x86_emulate_ctxt *ctxt) > return X86EMUL_CONTINUE; > } > > +static int em_clflushopt(struct x86_emulate_ctxt *ctxt) > +{ > + /* emulating clflushopt regardless of cpuid */ > + return X86EMUL_CONTINUE; > +} > + > static int em_movsxd(struct x86_emulate_ctxt *ctxt) > { > ctxt->dst.val = (s32) ctxt->src.val; > @@ -4585,7 +4591,7 @@ static const struct opcode group11[] = { > }; > > static const struct gprefix pfx_0f_ae_7 = { > - I(SrcMem | ByteOp, em_clflush), N, N, N, > + I(SrcMem | ByteOp, em_clflush), I(SrcMem | ByteOp, em_clflushopt), N, N, > }; > > static const struct group_dual group15 = { { > Queued, thanks. Paolo
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 0d917eb70319..56cae1ff9e3f 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -4046,6 +4046,12 @@ static int em_clflush(struct x86_emulate_ctxt *ctxt) return X86EMUL_CONTINUE; } +static int em_clflushopt(struct x86_emulate_ctxt *ctxt) +{ + /* emulating clflushopt regardless of cpuid */ + return X86EMUL_CONTINUE; +} + static int em_movsxd(struct x86_emulate_ctxt *ctxt) { ctxt->dst.val = (s32) ctxt->src.val; @@ -4585,7 +4591,7 @@ static const struct opcode group11[] = { }; static const struct gprefix pfx_0f_ae_7 = { - I(SrcMem | ByteOp, em_clflush), N, N, N, + I(SrcMem | ByteOp, em_clflush), I(SrcMem | ByteOp, em_clflushopt), N, N, }; static const struct group_dual group15 = { {
The instruction emulator ignores clflush instructions, yet fails to support clflushopt. Treat both similarly. Fixes: 13e457e0eebf ("KVM: x86: Emulator does not decode clflush well") Signed-off-by: David Edmondson <david.edmondson@oracle.com> --- arch/x86/kvm/emulate.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)