diff options
| author | Gleb Natapov <gleb@redhat.com> | 2010-02-10 14:21:31 +0200 |
|---|---|---|
| committer | Marcelo Tosatti <mtosatti@redhat.com> | 2010-03-01 12:36:11 -0300 |
| commit | a0044755679f3e761b8b95995e5f2db2b7efd0f6 (patch) | |
| tree | 3a4db9d3e0512109130c2f4f1f425305378c0a27 | |
| parent | 60a29d4ea4e7b6b95d9391ebc8625b0426f3a363 (diff) | |
KVM: x86 emulator: Add Virtual-8086 mode of emulation
For some instructions CPU behaves differently for real-mode and
virtual 8086. Let emulator know which mode cpu is in, so it will
not poke into vcpu state directly.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
| -rw-r--r-- | arch/x86/include/asm/kvm_emulate.h | 1 | ||||
| -rw-r--r-- | arch/x86/kvm/emulate.c | 12 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.c | 3 |
3 files changed, 10 insertions, 6 deletions
diff --git a/arch/x86/include/asm/kvm_emulate.h b/arch/x86/include/asm/kvm_emulate.h index 9b697c2735d9..784d7c586d8e 100644 --- a/arch/x86/include/asm/kvm_emulate.h +++ b/arch/x86/include/asm/kvm_emulate.h @@ -168,6 +168,7 @@ struct x86_emulate_ctxt { /* Execution mode, passed to the emulator. */ #define X86EMUL_MODE_REAL 0 /* Real mode. */ +#define X86EMUL_MODE_VM86 1 /* Virtual 8086 mode. */ #define X86EMUL_MODE_PROT16 2 /* 16-bit protected mode. */ #define X86EMUL_MODE_PROT32 4 /* 32-bit protected mode. */ #define X86EMUL_MODE_PROT64 8 /* 64-bit (long) mode. */ diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 45a4f7c1bb0b..e4e2df3b6038 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -899,6 +899,7 @@ x86_decode_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) switch (mode) { case X86EMUL_MODE_REAL: + case X86EMUL_MODE_VM86: case X86EMUL_MODE_PROT16: def_op_bytes = def_ad_bytes = 2; break; @@ -1525,7 +1526,7 @@ emulate_syscall(struct x86_emulate_ctxt *ctxt) /* syscall is not available in real mode */ if (c->lock_prefix || ctxt->mode == X86EMUL_MODE_REAL - || !is_protmode(ctxt->vcpu)) + || ctxt->mode == X86EMUL_MODE_VM86) return -1; setup_syscalls_segments(ctxt, &cs, &ss); @@ -1577,8 +1578,8 @@ emulate_sysenter(struct x86_emulate_ctxt *ctxt) if (c->lock_prefix) return -1; - /* inject #GP if in real mode or paging is disabled */ - if (ctxt->mode == X86EMUL_MODE_REAL || !is_protmode(ctxt->vcpu)) { + /* inject #GP if in real mode */ + if (ctxt->mode == X86EMUL_MODE_REAL) { kvm_inject_gp(ctxt->vcpu, 0); return -1; } @@ -1642,8 +1643,9 @@ emulate_sysexit(struct x86_emulate_ctxt *ctxt) if (c->lock_prefix) return -1; - /* inject #GP if in real mode or paging is disabled */ - if (ctxt->mode == X86EMUL_MODE_REAL || !is_protmode(ctxt->vcpu)) { + /* inject #GP if in real mode or Virtual 8086 mode */ + if (ctxt->mode == X86EMUL_MODE_REAL || + ctxt->mode == X86EMUL_MODE_VM86) { kvm_inject_gp(ctxt->vcpu, 0); return -1; } diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index b2f91b9af00d..a28379507d30 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -3348,8 +3348,9 @@ int emulate_instruction(struct kvm_vcpu *vcpu, vcpu->arch.emulate_ctxt.vcpu = vcpu; vcpu->arch.emulate_ctxt.eflags = kvm_get_rflags(vcpu); vcpu->arch.emulate_ctxt.mode = + (!is_protmode(vcpu)) ? X86EMUL_MODE_REAL : (vcpu->arch.emulate_ctxt.eflags & X86_EFLAGS_VM) - ? X86EMUL_MODE_REAL : cs_l + ? X86EMUL_MODE_VM86 : cs_l ? X86EMUL_MODE_PROT64 : cs_db ? X86EMUL_MODE_PROT32 : X86EMUL_MODE_PROT16; |