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SubjectRe: [PATCH 3/4 V10] Add ioctl for KVMCLOCK_GUEST_STOPPED
On 01/30/2012 06:18 PM, Jan Kiszka wrote:
> >
> > This looks racy. The vcpu can remove its kvmclock concurrently with
> > this access, and src will be NULL.
>
> There is no race here (src is member of the vcpu), but arch.time might
> have become invalid. KVM_REQ_CLOCK_UPDATE instead of mark_page_dirty
> would indeed be the way to go. Trivial solution, I would say.
>
> However, the concept of "guest stopped" has VM, not VCPU scope.

We're not stopping the guest here, just setting a flag in kvmclock,
which certainly is a per-vcpu thing.

> That
> makes the call more appropriate as a VM ioctl. If that thing should
> really become per-vcpu, at least call it KVMCLOCK_VCPU_STOPPED.
>

All current ioctls start with KVM_. Maybe KVM_KVMCLOCK_CTRL?

--
error compiling committee.c: too many arguments to function



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