KVM: X86: Kill off ctxt->ud

ctxt->ud is consumed only by x86_decode_insn(), we can kill it off by
passing emulation_type to x86_decode_insn() and dropping ctxt->ud
altogether. Tracking that info in ctxt for literally one call is silly.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Message-Id: <1622160097-37633-2-git-send-email-wanpengli@tencent.com>
This commit is contained in:
Wanpeng Li 2021-05-27 17:01:37 -07:00 committed by Paolo Bonzini
parent da6393cdd8
commit b35491e66c
3 changed files with 5 additions and 7 deletions

View File

@ -5111,7 +5111,7 @@ done:
return rc;
}
int x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len)
int x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len, int emulation_type)
{
int rc = X86EMUL_CONTINUE;
int mode = ctxt->mode;
@ -5322,7 +5322,8 @@ done_prefixes:
ctxt->execute = opcode.u.execute;
if (unlikely(ctxt->ud) && likely(!(ctxt->d & EmulateOnUD)))
if (unlikely(emulation_type & EMULTYPE_TRAP_UD) &&
likely(!(ctxt->d & EmulateOnUD)))
return EMULATION_FAILED;
if (unlikely(ctxt->d &

View File

@ -314,7 +314,6 @@ struct x86_emulate_ctxt {
int interruptibility;
bool perm_ok; /* do not check permissions if true */
bool ud; /* inject an #UD if host doesn't support insn */
bool tf; /* TF value before instruction (after for syscall/sysret) */
bool have_exception;
@ -491,7 +490,7 @@ enum x86_intercept {
#define X86EMUL_MODE_HOST X86EMUL_MODE_PROT64
#endif
int x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len);
int x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len, int emulation_type);
bool x86_page_table_writing_insn(struct x86_emulate_ctxt *ctxt);
#define EMULATION_FAILED -1
#define EMULATION_OK 0

View File

@ -7568,9 +7568,7 @@ int x86_decode_emulated_instruction(struct kvm_vcpu *vcpu, int emulation_type,
kvm_vcpu_check_breakpoint(vcpu, &r))
return r;
ctxt->ud = emulation_type & EMULTYPE_TRAP_UD;
r = x86_decode_insn(ctxt, insn, insn_len);
r = x86_decode_insn(ctxt, insn, insn_len, emulation_type);
trace_kvm_emulate_insn_start(vcpu);
++vcpu->stat.insn_emulation;