The patch titled Subject: mm/slab: fix cpu on/off handling has been added to the -mm tree. Its filename is mm-slab-use-percpu-allocator-for-cpu-cache-fix.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/mm-slab-use-percpu-allocator-for-cpu-cache-fix.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/mm-slab-use-percpu-allocator-for-cpu-cache-fix.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> Subject: mm/slab: fix cpu on/off handling When cpu off, we flush all cpu cached objects to it's own slab. free_block() is used for this purpose and it's role is just to flush objects from array_cache to proper slab. It doesn't adjust array_cache's internal fields so we should manually reset them to proper value. Without this fix, we maintain free objects duplicately, one is in cpu cache, and, the other one is in the slab. So system would be broken. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> Reported-by: Jeremiah Mahler <jmmahler@xxxxxxxxx> Cc: Christoph Lameter <cl@xxxxxxxxx> Cc: Pekka Enberg <penberg@xxxxxxxxxx> Cc: David Rientjes <rientjes@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/slab.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff -puN mm/slab.c~mm-slab-use-percpu-allocator-for-cpu-cache-fix mm/slab.c --- a/mm/slab.c~mm-slab-use-percpu-allocator-for-cpu-cache-fix +++ a/mm/slab.c @@ -1102,8 +1102,10 @@ static void cpuup_canceled(long cpu) /* cpu is dead; no one can alloc from it. */ nc = per_cpu_ptr(cachep->cpu_cache, cpu); - if (nc) + if (nc) { free_block(cachep, nc->entry, nc->avail, node, &list); + nc->avail = 0; + } if (!cpumask_empty(mask)) { spin_unlock_irq(&n->list_lock); _ Patches currently in -mm which might be from iamjoonsoo.kim@xxxxxxx are mm-slab_commonc-suppress-warning.patch mm-slab_common-move-kmem_cache-definition-to-internal-header.patch mm-slab_common-move-kmem_cache-definition-to-internal-header-fix.patch mm-slab_common-move-kmem_cache-definition-to-internal-header-fix-2.patch mm-slab_common-move-kmem_cache-definition-to-internal-header-fix-2-fix.patch mm-slb-always-track-caller-in-kmalloc_node_track_caller.patch mm-slab-move-cache_flusharray-out-of-unlikelytext-section.patch mm-slab-noinline-__ac_put_obj.patch mm-slab-factor-out-unlikely-part-of-cache_free_alien.patch slub-disable-tracing-and-failslab-for-merged-slabs.patch topology-add-support-for-node_to_mem_node-to-determine-the-fallback-node.patch slub-fallback-to-node_to_mem_node-node-if-allocating-on-memoryless-node.patch partial-revert-of-81c98869faa5-kthread-ensure-locality-of-task_struct-allocations.patch slab-fix-for_each_kmem_cache_node.patch mm-slab_common-commonize-slab-merge-logic.patch mm-slab_common-commonize-slab-merge-logic-fix.patch mm-slab-support-slab-merge.patch mm-slab-use-percpu-allocator-for-cpu-cache.patch mm-slab-use-percpu-allocator-for-cpu-cache-fix.patch mm-cma-adjust-address-limit-to-avoid-hitting-low-high-memory-boundary.patch arm-mm-dont-limit-default-cma-region-only-to-low-memory.patch mm-page_alloc-determine-migratetype-only-once.patch mm-thp-dont-hold-mmap_sem-in-khugepaged-when-allocating-thp.patch mm-compaction-defer-each-zone-individually-instead-of-preferred-zone.patch mm-compaction-defer-each-zone-individually-instead-of-preferred-zone-fix.patch mm-compaction-do-not-count-compact_stall-if-all-zones-skipped-compaction.patch mm-compaction-do-not-recheck-suitable_migration_target-under-lock.patch mm-compaction-move-pageblock-checks-up-from-isolate_migratepages_range.patch mm-compaction-move-pageblock-checks-up-from-isolate_migratepages_range-fix.patch mm-compaction-reduce-zone-checking-frequency-in-the-migration-scanner.patch mm-compaction-khugepaged-should-not-give-up-due-to-need_resched.patch mm-compaction-khugepaged-should-not-give-up-due-to-need_resched-fix.patch mm-compaction-remember-position-within-pageblock-in-free-pages-scanner.patch mm-compaction-skip-buddy-pages-by-their-order-in-the-migrate-scanner.patch mm-rename-allocflags_to_migratetype-for-clarity.patch mm-compaction-pass-gfp-mask-to-compact_control.patch mm-use-__seq_open_private-instead-of-seq_open.patch memcg-move-memcg_allocfree_cache_params-to-slab_commonc.patch memcg-dont-call-memcg_update_all_caches-if-new-cache-id-fits.patch memcg-move-memcg_update_cache_size-to-slab_commonc.patch drivers-dma-coherent-add-initialization-from-device-tree.patch drivers-dma-coherent-add-initialization-from-device-tree-fix.patch drivers-dma-coherent-add-initialization-from-device-tree-fix-fix.patch drivers-dma-coherent-add-initialization-from-device-tree-checkpatch-fixes.patch drivers-dma-contiguous-add-initialization-from-device-tree.patch drivers-dma-contiguous-add-initialization-from-device-tree-checkpatch-fixes.patch zsmalloc-move-pages_allocated-to-zs_pool.patch zsmalloc-change-return-value-unit-of-zs_get_total_size_bytes.patch zram-zram-memory-size-limitation.patch zram-report-maximum-used-memory.patch page-owners-correct-page-order-when-to-free-page.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html