On Wed, 02 Nov 2022 16:23:16 +0000,
Peter Xu <peterx@xxxxxxxxxx> wrote:
>
> Might be slightly off-topic: I didn't quickly spot how do we guarantee two
> threads doing KVM_RUN ioctl on the same vcpu fd concurrently. I know
> that's insane and could have corrupted things, but I just want to make sure
> e.g. even a malicious guest app won't be able to trigger host warnings.
In kvm_vcpu_ioctl():
if (mutex_lock_killable(&vcpu->mutex)) <----- this
return -EINTR;
switch (ioctl) {
case KVM_RUN: {
struct pid *oldpid;
r = -EINVAL;
if (arg)
We simply don't allow two concurrent ioctls to the same vcpu, let
alone two KVM_RUN.
M.
--
Without deviation from the norm, progress is not possible.
