Re: [PATCH v4 2/4] hugetlb/userfaultfd: Forbid huge pmd sharing when uffd enabled

On Wed, 10 Mar 2021 at 22:27, Peter Xu wrote: > > On Wed, Mar 10, 2021 at 01:18:42PM +0530, Naresh Kamboju wrote: > > Hi Peter, > > Hi, Naresh, > > > > > On Fri, 19 Feb 2021 at 04:43, Peter Xu wrote: > > > > > > Huge pmd sharing could bring problem to userfaultfd. The thing is that > > >

Re: [PATCH v4 2/4] hugetlb/userfaultfd: Forbid huge pmd sharing when uffd enabled

On Wed, Mar 10, 2021 at 01:18:42PM +0530, Naresh Kamboju wrote: > Hi Peter, Hi, Naresh, > > On Fri, 19 Feb 2021 at 04:43, Peter Xu wrote: > > > > Huge pmd sharing could bring problem to userfaultfd. The thing is that > > userfaultfd is running its logic based on the special bits on page table

Re: [PATCH v4 2/4] hugetlb/userfaultfd: Forbid huge pmd sharing when uffd enabled

Hi Peter, On Fri, 19 Feb 2021 at 04:43, Peter Xu wrote: > > Huge pmd sharing could bring problem to userfaultfd. The thing is that > userfaultfd is running its logic based on the special bits on page table > entries, however the huge pmd sharing could potentially share page table > entries for

[PATCH v4 2/4] hugetlb/userfaultfd: Forbid huge pmd sharing when uffd enabled

Huge pmd sharing could bring problem to userfaultfd. The thing is that userfaultfd is running its logic based on the special bits on page table entries, however the huge pmd sharing could potentially share page table entries for different address ranges. That could cause issues on either: -