Re: [PATCH 09/13] KVM: MMU: get expected spte out of mmu-lock

Avi Kivity
2012-04-09T13:22:17Z

On 04/09/2012 04:16 PM, Takuya Yoshikawa wrote:
> On Mon, 09 Apr 2012 15:28:47 +0300
> Avi Kivity <avi@redhat.com> wrote:
>
> > Ah, so it's protecting two paths at the same time: rmap.write_protect ->
> > fast page fault, and lock(sptep) -> write protect.
> >
> > The whole thing needs to be documented very carefully in locking.txt,
> > otherwise mmu.c will be write-protected to everyone except you.
>
> Before changing mmu_lock usage, better describe it in locking.txt.
>
> I guess from mmu.c git history, it is already restricted to a few
> people who can describe that.

It's getting harder and harder, yes.

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