Messages in this thread | | | Date | Fri, 2 Nov 2018 18:25:16 +0300 | From | "Kirill A. Shutemov" <> | Subject | Re: [PATCH] mremap: properly flush TLB before releasing the page |
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On Fri, Nov 02, 2018 at 04:00:17PM +0100, Jann Horn wrote: > On Fri, Nov 2, 2018 at 3:56 PM Kirill A. Shutemov <kirill@shutemov.name> wrote: > > On Fri, Nov 02, 2018 at 01:22:42PM +0000, Will Deacon wrote: > > > From: Linus Torvalds <torvalds@linux-foundation.org> > > > > > > Commit eb66ae030829605d61fbef1909ce310e29f78821 upstream. > > > > I have never seen the original patch on mailing lists, so I'll reply to > > the backport. > > For context, the original bug report is public at > https://bugs.chromium.org/p/project-zero/issues/detail?id=1695 .
Okay. I see.
I wounder if it would be cheaper to fix this by taking i_mmap_lock_write() unconditionally in mremap() path rather than do a lot of flushing. We take the lock now only to remap to lower addresses.
-- Kirill A. Shutemov
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