diff options
| author | Nelson Elhage <nelhage@ksplice.com> | 2011-04-18 12:05:53 -0400 |
|---|---|---|
| committer | Avi Kivity <avi@redhat.com> | 2011-05-11 07:57:10 -0400 |
| commit | 3d9b938eefb7d91a1ae13e425931bd5ac103b762 (patch) | |
| tree | 96ecffc81c09cc5578a5375cb357895084b552fa /arch/x86 | |
| parent | 7c4c0f4fd5c3e82234c0ab61c7e7ffdb8f3af07b (diff) | |
KVM: emulator: Use linearize() when fetching instructions
Since segments need to be handled slightly differently when fetching
instructions, we add a __linearize helper that accepts a new 'fetch' boolean.
[avi: fix oops caused by wrong segmented_address initialization order]
Signed-off-by: Nelson Elhage <nelhage@ksplice.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/include/asm/kvm_emulate.h | 1 | ||||
| -rw-r--r-- | arch/x86/kvm/emulate.c | 26 |
2 files changed, 18 insertions, 9 deletions
diff --git a/arch/x86/include/asm/kvm_emulate.h b/arch/x86/include/asm/kvm_emulate.h index 081844860a3..9b760c8f257 100644 --- a/arch/x86/include/asm/kvm_emulate.h +++ b/arch/x86/include/asm/kvm_emulate.h @@ -265,7 +265,6 @@ struct x86_emulate_ctxt { unsigned long eip; /* eip before instruction emulation */ /* Emulated execution mode, represented by an X86EMUL_MODE value. */ int mode; - u32 cs_base; /* interruptibility state, as a result of execution of STI or MOV SS */ int interruptibility; diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 4c5ff22d101..e1f77de9540 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -540,9 +540,9 @@ static int emulate_nm(struct x86_emulate_ctxt *ctxt) return emulate_exception(ctxt, NM_VECTOR, 0, false); } -static int linearize(struct x86_emulate_ctxt *ctxt, +static int __linearize(struct x86_emulate_ctxt *ctxt, struct segmented_address addr, - unsigned size, bool write, + unsigned size, bool write, bool fetch, ulong *linear) { struct decode_cache *c = &ctxt->decode; @@ -569,7 +569,7 @@ static int linearize(struct x86_emulate_ctxt *ctxt, if (((desc.type & 8) || !(desc.type & 2)) && write) goto bad; /* unreadable code segment */ - if ((desc.type & 8) && !(desc.type & 2)) + if (!fetch && (desc.type & 8) && !(desc.type & 2)) goto bad; lim = desc_limit_scaled(&desc); if ((desc.type & 8) || !(desc.type & 4)) { @@ -602,7 +602,7 @@ static int linearize(struct x86_emulate_ctxt *ctxt, } break; } - if (c->ad_bytes != 8) + if (fetch ? ctxt->mode != X86EMUL_MODE_PROT64 : c->ad_bytes != 8) la &= (u32)-1; *linear = la; return X86EMUL_CONTINUE; @@ -613,6 +613,15 @@ bad: return emulate_gp(ctxt, addr.seg); } +static int linearize(struct x86_emulate_ctxt *ctxt, + struct segmented_address addr, + unsigned size, bool write, + ulong *linear) +{ + return __linearize(ctxt, addr, size, write, false, linear); +} + + static int segmented_read_std(struct x86_emulate_ctxt *ctxt, struct segmented_address addr, void *data, @@ -637,11 +646,13 @@ static int do_fetch_insn_byte(struct x86_emulate_ctxt *ctxt, int size, cur_size; if (eip == fc->end) { - unsigned long linear = eip + ctxt->cs_base; - if (ctxt->mode != X86EMUL_MODE_PROT64) - linear &= (u32)-1; + unsigned long linear; + struct segmented_address addr = { .seg=VCPU_SREG_CS, .ea=eip}; cur_size = fc->end - fc->start; size = min(15UL - cur_size, PAGE_SIZE - offset_in_page(eip)); + rc = __linearize(ctxt, addr, size, false, true, &linear); + if (rc != X86EMUL_CONTINUE) + return rc; rc = ops->fetch(linear, fc->data + cur_size, size, ctxt->vcpu, &ctxt->exception); if (rc != X86EMUL_CONTINUE) @@ -3127,7 +3138,6 @@ x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len) c->fetch.end = c->fetch.start + insn_len; if (insn_len > 0) memcpy(c->fetch.data, insn, insn_len); - ctxt->cs_base = seg_base(ctxt, ops, VCPU_SREG_CS); switch (mode) { case X86EMUL_MODE_REAL: |