diff options
author | Peter Xu <peterx@redhat.com> | 2017-12-12 19:15:02 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-11-04 16:52:47 +0300 |
commit | 871424f0c3cfcf51727cb56a0a5f1cbfc9e429c6 (patch) | |
tree | d01eb0db67a1f45a3a131e14228e497c8768ec12 | |
parent | 3642e35447495208665e30ffbc2466a2a488b99e (diff) | |
download | linux-871424f0c3cfcf51727cb56a0a5f1cbfc9e429c6.tar.xz |
kvm: x86: fix WARN due to uninitialized guest FPU state
commit 5663d8f9bbe4bf15488f7351efb61ea20fa6de06 upstream
------------[ cut here ]------------
Bad FPU state detected at kvm_put_guest_fpu+0xd8/0x2d0 [kvm], reinitializing FPU registers.
WARNING: CPU: 1 PID: 4594 at arch/x86/mm/extable.c:103 ex_handler_fprestore+0x88/0x90
CPU: 1 PID: 4594 Comm: qemu-system-x86 Tainted: G B OE 4.15.0-rc2+ #10
RIP: 0010:ex_handler_fprestore+0x88/0x90
Call Trace:
fixup_exception+0x4e/0x60
do_general_protection+0xff/0x270
general_protection+0x22/0x30
RIP: 0010:kvm_put_guest_fpu+0xd8/0x2d0 [kvm]
RSP: 0018:ffff8803d5627810 EFLAGS: 00010246
kvm_vcpu_reset+0x3b4/0x3c0 [kvm]
kvm_apic_accept_events+0x1c0/0x240 [kvm]
kvm_arch_vcpu_ioctl_run+0x1658/0x2fb0 [kvm]
kvm_vcpu_ioctl+0x479/0x880 [kvm]
do_vfs_ioctl+0x142/0x9a0
SyS_ioctl+0x74/0x80
do_syscall_64+0x15f/0x600
where kvm_put_guest_fpu is called without a prior kvm_load_guest_fpu.
To fix it, move kvm_load_guest_fpu to the very beginning of
kvm_arch_vcpu_ioctl_run.
Cc: stable@vger.kernel.org
Fixes: f775b13eedee2f7f3c6fdd4e90fb79090ce5d339
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
-rw-r--r-- | arch/x86/kvm/x86.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 3856828ee1dc..8d688b213504 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -7393,13 +7393,12 @@ static int complete_emulated_mmio(struct kvm_vcpu *vcpu) int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) { - struct fpu *fpu = ¤t->thread.fpu; int r; - fpu__initialize(fpu); - kvm_sigset_activate(vcpu); + kvm_load_guest_fpu(vcpu); + if (unlikely(vcpu->arch.mp_state == KVM_MP_STATE_UNINITIALIZED)) { if (kvm_run->immediate_exit) { r = -EINTR; @@ -7440,6 +7439,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) r = vcpu_run(vcpu); out: + kvm_put_guest_fpu(vcpu); post_kvm_run_save(vcpu); kvm_sigset_deactivate(vcpu); |