From: David Edmondson david.edmondson@oracle.com
commit 51b958e5aeb1e18c00332e0b37c5d4e95a3eff84 upstream.
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 Message-Id: 20201103120400.240882-1-david.edmondson@oracle.com Reviewed-by: Joao Martins joao.m.martins@oracle.com Signed-off-by: Paolo Bonzini pbonzini@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/x86/kvm/emulate.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
--- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -3994,6 +3994,12 @@ static int em_clflush(struct x86_emulate 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; @@ -4507,7 +4513,7 @@ 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 = { {