lkml.org 
[lkml]   [2021]   [Feb]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 0/2] KVM: do not assume PTE is writable after follow_pfn
On Mon, Feb 08, 2021 at 05:02:59PM -0500, Peter Xu wrote:
> On Mon, Feb 08, 2021 at 02:51:33PM -0400, Jason Gunthorpe wrote:
> > On Fri, Feb 05, 2021 at 01:14:11PM -0500, Peter Xu wrote:
> >
> > > But I do have a question on why dax as the only user needs to pass in the
> > > notifier to follow_pte() for initialization.
> >
> > Not sure either, why does DAX opencode something very much like
> > page_mkclean() with dax_entry_mkclean()?
> >
> > Also it looks like DAX uses the wrong notifier, it calls
> > MMU_NOTIFY_CLEAR but page_mkclean_one() uses
> > MMU_NOTIFY_PROTECTION_PAGE for the same PTE modification sequence??
> >
> > page_mkclean() has some technique to make the notifier have the right
> > size without becoming entangled in the PTL locks..
>
> Right. I guess it's because dax doesn't have "struct page*" on the
> back, so it

It doesn't? I thought DAX cases did?

Jason

\
 
 \ /
  Last update: 2021-02-09 00:28    [W:0.142 / U:0.696 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site