Messages in this thread | | | Date | Mon, 23 Aug 2021 11:15:40 +0200 | From | Oscar Salvador <> | Subject | Re: [PATCH 2/3] mm/memory_hotplug: fix potential permanent lru cache disable |
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On 2021-08-21 11:42, Miaohe Lin wrote: > If offline_pages failed after lru_cache_disable(), it forgot to do > lru_cache_enable() in error path. So we would have lru cache disabled > permanently in this case. > > Fixes: d479960e44f2 ("mm: disable LRU pagevec during the migration > temporarily") > Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Should this go to stable? In case we fail to enable it again, we will bypass the pvec cache anytime we add a new page to the LRU which might lead to severe performance regression?
> --- > mm/memory_hotplug.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c > index d986d3791986..9fd0be32a281 100644 > --- a/mm/memory_hotplug.c > +++ b/mm/memory_hotplug.c > @@ -2033,6 +2033,7 @@ int __ref offline_pages(unsigned long start_pfn, > unsigned long nr_pages, > undo_isolate_page_range(start_pfn, end_pfn, MIGRATE_MOVABLE); > memory_notify(MEM_CANCEL_OFFLINE, &arg); > failed_removal_pcplists_disabled: > + lru_cache_enable(); > zone_pcp_enable(zone); > failed_removal: > pr_debug("memory offlining [mem %#010llx-%#010llx] failed due to > %s\n",
-- Oscar Salvador SUSE L3
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