Messages in this thread | | | From | Yang Shi <> | Date | Tue, 17 Jan 2023 10:57:47 -0800 | Subject | Re: [PATCH] mm/khugepaged: Fix ->anon_vma race |
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On Sun, Jan 15, 2023 at 11:07 AM Kirill A. Shutemov <kirill@shutemov.name> wrote: > > On Fri, Jan 13, 2023 at 08:28:59PM +0100, Jann Horn wrote: > > No, that lockdep assert has to be there. Page table traversal is > > allowed under any one of the mmap lock, the anon_vma lock (if the VMA > > is associated with an anon_vma), and the mapping lock (if the VMA is > > associated with a mapping); and so to be able to remove page tables, > > we must hold all three of them. > > Okay, that's fair. I agree with the patch now. Maybe adjust the commit > message a bit?
Yeah, the explanation makes sense to me too. Reviewed-by: Yang Shi <shy828301@gmail.com>
> > Anyway: > > Acked-by: Kirill A. Shutemov <kirill.shutemov@intel.linux.com> > > BTW, I've noticied that you recently added tlb_remove_table_sync_one(). > I'm not sure why it is needed. Why IPI in pmdp_collapse_flush() in not > good enough to serialize against GUP fast? > > -- > Kiryl Shutsemau / Kirill A. Shutemov
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