KVM: Provide current eip as part of emulator context.

Eliminate the need to call back into KVM to get it from emulator.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

3 files changed, 9 insertions, 7 deletions

diff --git a/arch/x86/include/asm/kvm_emulate.h b/arch/x86/include/asm/kvm_emulate.h
index b048fd21c54e..07657258af8f 100644
--- a/arch/x86/include/asm/kvm_emulate.h
+++ b/arch/x86/include/asm/kvm_emulate.h
@@ -141,7 +141,7 @@ struct decode_cache {
         u8 seg_override;
         unsigned int d;
         unsigned long regs[NR_VCPU_REGS];
-        unsigned long eip, eip_orig;
+        unsigned long eip;
         /* modrm */
         u8 modrm;
         u8 modrm_mod;
@@ -160,6 +160,7 @@ struct x86_emulate_ctxt {
         struct kvm_vcpu *vcpu;
 
         unsigned long eflags;
+        unsigned long eip; /* eip before instruction emulation */
         /* Emulated execution mode, represented by an X86EMUL_MODE value. */
         int mode;
         u32 cs_base;
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 8bd05571672c..2c27aa466cf4 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -667,7 +667,7 @@ static int do_insn_fetch(struct x86_emulate_ctxt *ctxt,
         int rc;
 
         /* x86 instructions are limited to 15 bytes. */
-        if (eip + size - ctxt->decode.eip_orig > 15)
+        if (eip + size - ctxt->eip > 15)
                 return X86EMUL_UNHANDLEABLE;
         eip += ctxt->cs_base;
         while (size--) {
@@ -927,7 +927,7 @@ x86_decode_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
         /* Shadow copy of register state. Committed on successful emulation. */
 
         memset(c, 0, sizeof(struct decode_cache));
-        c->eip = c->eip_orig = kvm_rip_read(ctxt->vcpu);
+        c->eip = ctxt->eip;
         ctxt->cs_base = seg_base(ctxt, VCPU_SREG_CS);
         memcpy(c->regs, ctxt->vcpu->arch.regs, sizeof c->regs);
 
@@ -1878,7 +1878,7 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
                         }
                 }
                 register_address_increment(c, &c->regs[VCPU_REGS_RCX], -1);
-                c->eip = kvm_rip_read(ctxt->vcpu);
+                c->eip = ctxt->eip;
         }
 
         if (c->src.type == OP_MEM) {
@@ -2447,7 +2447,7 @@ twobyte_insn:
                                 goto done;
 
                         /* Let the processor re-execute the fixed hypercall */
-                        c->eip = kvm_rip_read(ctxt->vcpu);
+                        c->eip = ctxt->eip;
                         /* Disable writeback. */
                         c->dst.type = OP_NONE;
                         break;
@@ -2551,7 +2551,7 @@ twobyte_insn:
                         | ((u64)c->regs[VCPU_REGS_RDX] << 32);
                 if (kvm_set_msr(ctxt->vcpu, c->regs[VCPU_REGS_RCX], msr_data)) {
                         kvm_inject_gp(ctxt->vcpu, 0);
-                        c->eip = kvm_rip_read(ctxt->vcpu);
+                        c->eip = ctxt->eip;
                 }
                 rc = X86EMUL_CONTINUE;
                 c->dst.type = OP_NONE;
@@ -2560,7 +2560,7 @@ twobyte_insn:
                 /* rdmsr */
                 if (kvm_get_msr(ctxt->vcpu, c->regs[VCPU_REGS_RCX], &msr_data)) {
                         kvm_inject_gp(ctxt->vcpu, 0);
-                        c->eip = kvm_rip_read(ctxt->vcpu);
+                        c->eip = ctxt->eip;
                 } else {
                         c->regs[VCPU_REGS_RAX] = (u32)msr_data;
                         c->regs[VCPU_REGS_RDX] = msr_data >> 32;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 9cb28a943c9a..0ecd37ac9d39 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3531,6 +3531,7 @@ int emulate_instruction(struct kvm_vcpu *vcpu,
 
                 vcpu->arch.emulate_ctxt.vcpu = vcpu;
                 vcpu->arch.emulate_ctxt.eflags = kvm_x86_ops->get_rflags(vcpu);
+                vcpu->arch.emulate_ctxt.eip = kvm_rip_read(vcpu);
                 vcpu->arch.emulate_ctxt.mode =
                         (!is_protmode(vcpu)) ? X86EMUL_MODE_REAL :
                         (vcpu->arch.emulate_ctxt.eflags & X86_EFLAGS_VM)