@@ -4002,13 +4002,15 @@ int hvm_msr_write_intercept(unsigned int msr, uint64_t msr_content,
void hvm_ud_intercept(struct cpu_user_regs *regs)
{
+ struct vcpu *cur = current;
+ bool should_emulate =
+ cur->domain->arch.x86_vendor != boot_cpu_data.x86_vendor;
struct hvm_emulate_ctxt ctxt;
hvm_emulate_init_once(&ctxt, regs);
if ( opt_hvm_fep )
{
- struct vcpu *cur = current;
const struct segment_register *cs = &ctxt.seg_reg[x86_seg_cs];
uint32_t walk = (ctxt.seg_reg[x86_seg_ss].attr.fields.dpl == 3)
? PFEC_user_mode : 0;
@@ -4032,9 +4034,17 @@ void hvm_ud_intercept(struct cpu_user_regs *regs)
regs->eip = regs->_eip;
add_taint(TAINT_HVM_FEP);
+
+ should_emulate = true;
}
}
+ if ( !should_emulate )
+ {
+ hvm_inject_hw_exception(TRAP_invalid_op, X86_EVENT_NO_EC);
+ return;
+ }
+
switch ( hvm_emulate_one(&ctxt) )
{
case X86EMUL_UNHANDLEABLE:
Having the instruction emulator fill in all #UDs when using FEP is unhelpful when trying to test emulation behaviour against hardware. Restrict emulation from the #UD intercept to the cross-vendor case, and when a postive Forced Emulation Prefix has been identified. Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> --- CC: Jan Beulich <JBeulich@suse.com> --- xen/arch/x86/hvm/hvm.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-)