Messages in this thread | | | Date | Fri, 5 Jun 2020 14:07:26 -0700 | From | Kees Cook <> | Subject | Re: [RFC PATCH 5/5] mm, slub: make reclaim_account attribute read-only |
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On Tue, Jun 02, 2020 at 04:15:19PM +0200, Vlastimil Babka wrote: > The attribute reflects the SLAB_RECLAIM_ACCOUNT cache flag. It's not clear why > this attribute was writable in the first place, as it's tied to how the cache > is used by its creator, it's not a user tunable. Furthermore: > > - it affects slab merging, but that's not being checked while toggled > - if affects whether __GFP_RECLAIMABLE flag is used to allocate page, but > the runtime toggle doesn't update allocflags > - it affects cache_vmstat_idx() so runtime toggle might lead to incosistency > of NR_SLAB_RECLAIMABLE and NR_SLAB_UNRECLAIMABLE > > Thus make it read-only. > > Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Kees Cook <keescook@chromium.org>
-- Kees Cook
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