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/machine.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) (limited to 'target-i386/machine.c') diff --git a/target-i386/machine.c b/target-i386/machine.c index bbeae8852c..d22a731789 100644 --- a/target-i386/machine.c +++ b/target-i386/machine.c @@ -290,6 +290,26 @@ static const VMStateDescription vmstate_async_pf_msr = { } }; +static bool fpop_ip_dp_needed(void *opaque) +{ + CPUState *env = opaque; + + return env->fpop != 0 || env->fpip != 0 || env->fpdp != 0; +} + +static const VMStateDescription vmstate_fpop_ip_dp = { + .name = "cpu/fpop_ip_dp", + .version_id = 1, + .minimum_version_id = 1, + .minimum_version_id_old = 1, + .fields = (VMStateField []) { + VMSTATE_UINT16_V(fpop, CPUState, 13), + VMSTATE_UINT64_V(fpip, CPUState, 13), + VMSTATE_UINT64_V(fpdp, CPUState, 13), + VMSTATE_END_OF_LIST() + } +}; + static const VMStateDescription vmstate_cpu = { .name = "cpu", .version_id = CPU_SAVE_VERSION, @@ -397,6 +417,9 @@ static const VMStateDescription vmstate_cpu = { { .vmsd = &vmstate_async_pf_msr, .needed = async_pf_msr_needed, + } , { + .vmsd = &vmstate_fpop_ip_dp, + .needed = fpop_ip_dp_needed, } , { /* empty */ } -- cgit v1.2.3