Messages in this thread | | | Date | Wed, 17 Oct 2018 09:19:06 -0700 | From | Christoph Hellwig <> | Subject | Re: [PATCH v2 1/2] mm: Add an F_SEAL_FS_WRITE seal to memfd |
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On Wed, Oct 17, 2018 at 08:44:01AM -0700, Daniel Colascione wrote: > > Even if no one changes these specific flags we still need a lock due > > to rmw cycles on the field. For example fadvise can set or clear > > FMODE_RANDOM. It seems to use file->f_lock for synchronization. > > Compare-and-exchange will suffice, right?
Only if all users use the compare and exchange, and right now they don't.
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