Re: missing kvm smp tlb flush in invlpg

Avi Kivity
2009-03-15T16:35:05Z

Andrea Arcangeli wrote:
> Ah so this was a proposed fix for this bug, I thought you were talking
> about different bugs, and you didn't acknowledge this as a bug sorry!
>
>

If ignoring bugs could make them go away...

> About the need_flush that could become a per-vcpu bit too cleared at
> every exit so perhaps we'll never have to flush, but it'd need to stay
> in the vcpu structure to avoid cacheline bouncing.
>

But then we need to set it for all vcpus on every invlpg. I'm assuming
invlpg is much more frequent than mmu notifiers, so it's better to keep
it global.

We've already taken a shared cacheline when we acquired mmu_lock.

btw, it's probably better to apply your patch, then adapt it to the
non-IPIing version; your patch is more suitable for -stable.

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