Messages in this thread |  | | Date | Mon, 8 Feb 2021 19:26:25 -0400 | From | Jason Gunthorpe <> | Subject | Re: [PATCH 0/2] KVM: do not assume PTE is writable after follow_pfn |
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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
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