From 42cc8fa620cbc73e349e96d84cf46469e828ec34 Mon Sep 17 00:00:00 2001 From: Jan Kiszka Date: Wed, 15 Jun 2011 15:17:26 +0200 Subject: kvm: x86: Save/restore FPU OP, IP and DP These FPU states are properly maintained by KVM but not yet by TCG. So far we unconditionally set them to 0 in the guest which may cause state corruptions, though not with modern guests. To avoid breaking backward migration, use a conditional subsection that is only written if any of the three fields is non-zero. The guest's FNINIT clears them frequently, and cleared IA32_MISC_ENABLE MSR[2] reduces the probability of non-zero values further so that this subsection is not expected to restrict migration in any common scenario. Signed-off-by: Jan Kiszka Signed-off-by: Avi Kivity --- target-i386/cpu.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'target-i386/cpu.h') diff --git a/target-i386/cpu.h b/target-i386/cpu.h index 9c3340da3f..cdf68ffd99 100644 --- a/target-i386/cpu.h +++ b/target-i386/cpu.h @@ -641,6 +641,10 @@ typedef struct CPUX86State { uint16_t fpuc; uint8_t fptags[8]; /* 0 = valid, 1 = empty */ FPReg fpregs[8]; + /* KVM-only so far */ + uint16_t fpop; + uint64_t fpip; + uint64_t fpdp; /* emulator internal variables */ float_status fp_status; -- cgit v1.2.3