diff options
| author | Borislav Petkov <bp@suse.de> | 2013-09-22 16:44:51 +0200 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2013-10-30 18:54:39 +0100 |
| commit | 1ce19dc16ce9136cccb6087e4a383ec9321980d9 (patch) | |
| tree | e93153a04096bf907dee183cc4b2260c5752991f /arch/x86 | |
| parent | 9c15bb1d0a8411f9bb3395d21d5309bde7da0c1c (diff) | |
kvm, emulator: Use opcode length
Add a field to the current emulation context which contains the
instruction opcode length. This will streamline handling of opcodes of
different length.
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/include/asm/kvm_emulate.h | 8 | ||||
| -rw-r--r-- | arch/x86/kvm/emulate.c | 5 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.c | 4 |
3 files changed, 11 insertions, 6 deletions
diff --git a/arch/x86/include/asm/kvm_emulate.h b/arch/x86/include/asm/kvm_emulate.h index 15f960c06ff..92a176ad456 100644 --- a/arch/x86/include/asm/kvm_emulate.h +++ b/arch/x86/include/asm/kvm_emulate.h @@ -279,8 +279,12 @@ struct x86_emulate_ctxt { bool have_exception; struct x86_exception exception; - /* decode cache */ - u8 twobyte; + /* + * decode cache + */ + + /* current opcode length in bytes */ + u8 opcode_len; u8 b; u8 intercept; u8 lock_prefix; diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index ddc3f3d2afd..d554d96afbc 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -4126,6 +4126,7 @@ int x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len) ctxt->_eip = ctxt->eip; ctxt->fetch.start = ctxt->_eip; ctxt->fetch.end = ctxt->fetch.start + insn_len; + ctxt->opcode_len = 1; if (insn_len > 0) memcpy(ctxt->fetch.data, insn, insn_len); @@ -4208,7 +4209,7 @@ done_prefixes: opcode = opcode_table[ctxt->b]; /* Two-byte opcode? */ if (ctxt->b == 0x0f) { - ctxt->twobyte = 1; + ctxt->opcode_len = 2; ctxt->b = insn_fetch(u8, ctxt); opcode = twobyte_table[ctxt->b]; } @@ -4540,7 +4541,7 @@ special_insn: goto writeback; } - if (ctxt->twobyte) + if (ctxt->opcode_len == 2) goto twobyte_insn; switch (ctxt->b) { diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 3d1e3ee8b39..d00d88455fe 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -4789,8 +4789,8 @@ static void inject_emulated_exception(struct kvm_vcpu *vcpu) static void init_decode_cache(struct x86_emulate_ctxt *ctxt) { - memset(&ctxt->twobyte, 0, - (void *)&ctxt->_regs - (void *)&ctxt->twobyte); + memset(&ctxt->opcode_len, 0, + (void *)&ctxt->_regs - (void *)&ctxt->opcode_len); ctxt->fetch.start = 0; ctxt->fetch.end = 0; |