diff options
| author | Sean Christopherson <[email protected]> | 2019-12-18 13:55:06 -0800 |
|---|---|---|
| committer | Paolo Bonzini <[email protected]> | 2020-01-24 09:19:05 +0100 |
| commit | 208050dac5ef4de5cb83ffcafa78499c94d0b5ad (patch) | |
| tree | f4bd295aa3a13360c1a20dd9eb9797402042e9f6 /scripts/gdb/linux/modules.py | |
| parent | 9d979c7e6ff43ca3200ffcb74f57415fd633a2da (diff) | |
KVM: x86: Remove spurious clearing of async #PF MSR
Remove a bogus clearing of apf.msr_val from kvm_arch_vcpu_destroy().
apf.msr_val is only set to a non-zero value by kvm_pv_enable_async_pf(),
which is only reachable by kvm_set_msr_common(), i.e. by writing
MSR_KVM_ASYNC_PF_EN. KVM does not autonomously write said MSR, i.e.
can only be written via KVM_SET_MSRS or KVM_RUN. Since KVM_SET_MSRS and
KVM_RUN are vcpu ioctls, they require a valid vcpu file descriptor.
kvm_arch_vcpu_destroy() is only called if KVM_CREATE_VCPU fails, and KVM
declares KVM_CREATE_VCPU successful once the vcpu fd is installed and
thus visible to userspace. Ergo, apf.msr_val cannot be non-zero when
kvm_arch_vcpu_destroy() is called.
Fixes: 344d9588a9df0 ("KVM: Add PV MSR to enable asynchronous page faults delivery.")
Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Paolo Bonzini <[email protected]>
Diffstat (limited to 'scripts/gdb/linux/modules.py')
0 files changed, 0 insertions, 0 deletions