diff options
| author | Avi Kivity <avi@redhat.com> | 2012-04-09 18:39:59 +0300 |
|---|---|---|
| committer | Marcelo Tosatti <mtosatti@redhat.com> | 2012-04-16 20:36:15 -0300 |
| commit | 1c11b37669a5209bd11fb857a103634afef971e8 (patch) | |
| tree | 7919993ec26af1038a0aae32f8682c3f723ba5d6 | |
| parent | ae75954457eee0a608072368c5b477e40f378d7b (diff) | |
KVM: x86 emulator: add support for vector alignment
x86 defines three classes of vector instructions: explicitly
aligned (#GP(0) if unaligned, explicitly unaligned, and default
(which depends on the encoding: AVX is unaligned, SSE is aligned).
Add support for marking an instruction as explicitly aligned or
unaligned, and mark MOVDQU as unaligned.
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
| -rw-r--r-- | arch/x86/kvm/emulate.c | 30 |
1 files changed, 29 insertions, 1 deletions
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 83756223f8aa..6302e5c74341 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -142,6 +142,9 @@ #define Src2FS (OpFS << Src2Shift) #define Src2GS (OpGS << Src2Shift) #define Src2Mask (OpMask << Src2Shift) +#define Aligned ((u64)1 << 41) /* Explicitly aligned (e.g. MOVDQA) */ +#define Unaligned ((u64)1 << 42) /* Explicitly unaligned (e.g. MOVDQU) */ +#define Avx ((u64)1 << 43) /* Advanced Vector Extensions */ #define X2(x...) x, x #define X3(x...) X2(x), x @@ -557,6 +560,29 @@ static void set_segment_selector(struct x86_emulate_ctxt *ctxt, u16 selector, ctxt->ops->set_segment(ctxt, selector, &desc, base3, seg); } +/* + * x86 defines three classes of vector instructions: explicitly + * aligned, explicitly unaligned, and the rest, which change behaviour + * depending on whether they're AVX encoded or not. + * + * Also included is CMPXCHG16B which is not a vector instruction, yet it is + * subject to the same check. + */ +static bool insn_aligned(struct x86_emulate_ctxt *ctxt, unsigned size) +{ + if (likely(size < 16)) + return false; + + if (ctxt->d & Aligned) + return true; + else if (ctxt->d & Unaligned) + return false; + else if (ctxt->d & Avx) + return false; + else + return true; +} + static int __linearize(struct x86_emulate_ctxt *ctxt, struct segmented_address addr, unsigned size, bool write, bool fetch, @@ -621,6 +647,8 @@ static int __linearize(struct x86_emulate_ctxt *ctxt, } if (fetch ? ctxt->mode != X86EMUL_MODE_PROT64 : ctxt->ad_bytes != 8) la &= (u32)-1; + if (insn_aligned(ctxt, size) && ((la & (size - 1)) != 0)) + return emulate_gp(ctxt, 0); *linear = la; return X86EMUL_CONTINUE; bad: @@ -3415,7 +3443,7 @@ static struct opcode group11[] = { }; static struct gprefix pfx_0f_6f_0f_7f = { - N, N, N, I(Sse, em_movdqu), + N, N, N, I(Sse | Unaligned, em_movdqu), }; static struct opcode opcode_table[256] = { |