Re: [PATCH] kvm: Faults which trigger IO release the mmap_sem

Gleb Natapov
2014-09-17T11:42:15Z

On Wed, Sep 17, 2014 at 01:27:14PM +0200, Radim Krčmář wrote:
> 2014-09-17 13:26+0300, Gleb Natapov:
> > For async_pf_execute() you do not need to even retry. Next guest's page fault
> > will retry it for you.
>
> Wouldn't that be a waste of vmentries?
This is how it will work with or without this second gup. Page is not
mapped into a shadow page table on this path, it happens on a next fault.

--
Gleb.