The variable sc is NULL pointer in can_reclaim_anon_pages() when called from zone_reclaimable_pages(). Check it before setting swapcache_only. Reported-by: Sachin Sant <sachinp@xxxxxxxxxxxxx> Link: https://lore.kernel.org/linux-mm/F00144DE-2A3F-4463-8203-45E0D57E313E@xxxxxxxxxxxxx/T/ Fixes: 92039ae85e8d("mm: vmscan: try to reclaim swapcache pages if no swap space") Signed-off-by: Liu Shixin <liushixin2@xxxxxxxxxx> --- mm/vmscan.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index f1dc0dbf1cdb..5eb85ddf403f 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -617,7 +617,7 @@ static inline bool can_reclaim_anon_pages(struct mem_cgroup *memcg, if (get_nr_swap_pages() > 0) return true; /* Is there any swapcache pages to reclaim? */ - if (total_swapcache_pages() > 0) { + if (sc && total_swapcache_pages() > 0) { sc->swapcache_only = 1; return true; } @@ -626,7 +626,7 @@ static inline bool can_reclaim_anon_pages(struct mem_cgroup *memcg, if (mem_cgroup_get_nr_swap_pages(memcg) > 0) return true; /* Is there any swapcache pages in memcg to reclaim? */ - if (mem_cgroup_get_nr_swapcache_pages(memcg) > 0) { + if (sc && mem_cgroup_get_nr_swapcache_pages(memcg) > 0) { sc->swapcache_only = 1; return true; } -- 2.25.1
