diff options
| author | Vitaly Kuznetsov <vkuznets@redhat.com> | 2020-09-11 11:31:47 +0200 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2020-09-11 13:26:47 -0400 |
| commit | d831de177217cd494bfb99f2c849a0d40c2a7890 (patch) | |
| tree | c9f90eb09f762b9cdaff3767e4a1755d66b63837 | |
| parent | 7be74942f184fdfba34ddd19a0d995deb34d4a03 (diff) | |
KVM: x86: always allow writing '0' to MSR_KVM_ASYNC_PF_EN
Even without in-kernel LAPIC we should allow writing '0' to
MSR_KVM_ASYNC_PF_EN as we're not enabling the mechanism. In
particular, QEMU with 'kernel-irqchip=off' fails to start
a guest with
qemu-system-x86_64: error: failed to set MSR 0x4b564d02 to 0x0
Fixes: 9d3c447c72fb2 ("KVM: X86: Fix async pf caused null-ptr-deref")
Reported-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200911093147.484565-1-vkuznets@redhat.com>
[Actually commit the version proposed by Sean Christopherson. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| -rw-r--r-- | arch/x86/kvm/x86.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 432ef34b9ea91f..e3de0fe5af377c 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -2735,7 +2735,7 @@ static int kvm_pv_enable_async_pf(struct kvm_vcpu *vcpu, u64 data) return 1; if (!lapic_in_kernel(vcpu)) - return 1; + return data ? 1 : 0; vcpu->arch.apf.msr_en_val = data; |