From a0044755679f3e761b8b95995e5f2db2b7efd0f6 Mon Sep 17 00:00:00 2001 From: Gleb Natapov Date: Wed, 10 Feb 2010 14:21:31 +0200 Subject: 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 Cc: stable@kernel.org Signed-off-by: Avi Kivity --- arch/x86/kvm/emulate.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) (limited to 'arch/x86/kvm/emulate.c') diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 45a4f7c..e4e2df3 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; } -- cgit v1.1