From d3fe959f81024072068e9ed86b39c2acfd7462a9 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= Date: Tue, 8 Nov 2016 20:54:16 +0100 Subject: [PATCH] KVM: x86: add Align16 instruction flag MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Needed for FXSAVE and FXRSTOR. Signed-off-by: Radim Krčmář Signed-off-by: Paolo Bonzini --- arch/x86/kvm/emulate.c | 20 ++++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-) diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index cbd7b92585bb..eb74d3b56e1c 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -171,6 +171,7 @@ #define NearBranch ((u64)1 << 52) /* Near branches */ #define No16 ((u64)1 << 53) /* No 16 bit operand */ #define IncSP ((u64)1 << 54) /* SP is incremented before ModRM calc */ +#define Aligned16 ((u64)1 << 55) /* Aligned to 16 byte boundary (e.g. FXSAVE) */ #define DstXacc (DstAccLo | SrcAccHi | SrcWrite) @@ -632,21 +633,24 @@ static void set_segment_selector(struct x86_emulate_ctxt *ctxt, u16 selector, * 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. + * subject to the same check. FXSAVE and FXRSTOR are checked here too as their + * 512 bytes of data must be aligned to a 16 byte boundary. */ -static bool insn_aligned(struct x86_emulate_ctxt *ctxt, unsigned size) +static unsigned insn_alignment(struct x86_emulate_ctxt *ctxt, unsigned size) { if (likely(size < 16)) - return false; + return 1; if (ctxt->d & Aligned) - return true; + return size; else if (ctxt->d & Unaligned) - return false; + return 1; else if (ctxt->d & Avx) - return false; + return 1; + else if (ctxt->d & Aligned16) + return 16; else - return true; + return size; } static __always_inline int __linearize(struct x86_emulate_ctxt *ctxt, @@ -704,7 +708,7 @@ static __always_inline int __linearize(struct x86_emulate_ctxt *ctxt, } break; } - if (insn_aligned(ctxt, size) && ((la & (size - 1)) != 0)) + if (la & (insn_alignment(ctxt, size) - 1)) return emulate_gp(ctxt, 0); return X86EMUL_CONTINUE; bad: -- 2.30.2