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@xxxxxxx> Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx> -- Kees Cook
