From: Greg Kroah-Hartman Date: Mon, 21 Sep 2020 16:40:14 +0000 (+0200) Subject: drop queue-5.4/mm-memcg-fix-memcg-reclaim-soft-lockup.patch X-Git-Tag: v4.4.237~2 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=399bb2b0e8e3dd3f5035eb33c2fd9b367a0cac4e;p=thirdparty%2Fkernel%2Fstable-queue.git drop queue-5.4/mm-memcg-fix-memcg-reclaim-soft-lockup.patch --- diff --git a/queue-5.4/mm-memcg-fix-memcg-reclaim-soft-lockup.patch b/queue-5.4/mm-memcg-fix-memcg-reclaim-soft-lockup.patch deleted file mode 100644 index ad47efebfb4..00000000000 --- a/queue-5.4/mm-memcg-fix-memcg-reclaim-soft-lockup.patch +++ /dev/null @@ -1,77 +0,0 @@ -From e3336cab2579012b1e72b5265adf98e2d6e244ad Mon Sep 17 00:00:00 2001 -From: Xunlei Pang -Date: Fri, 4 Sep 2020 16:35:27 -0700 -Subject: mm: memcg: fix memcg reclaim soft lockup - -From: Xunlei Pang - -commit e3336cab2579012b1e72b5265adf98e2d6e244ad upstream. - -We've met softlockup with "CONFIG_PREEMPT_NONE=y", when the target memcg -doesn't have any reclaimable memory. - -It can be easily reproduced as below: - - watchdog: BUG: soft lockup - CPU#0 stuck for 111s![memcg_test:2204] - CPU: 0 PID: 2204 Comm: memcg_test Not tainted 5.9.0-rc2+ #12 - Call Trace: - shrink_lruvec+0x49f/0x640 - shrink_node+0x2a6/0x6f0 - do_try_to_free_pages+0xe9/0x3e0 - try_to_free_mem_cgroup_pages+0xef/0x1f0 - try_charge+0x2c1/0x750 - mem_cgroup_charge+0xd7/0x240 - __add_to_page_cache_locked+0x2fd/0x370 - add_to_page_cache_lru+0x4a/0xc0 - pagecache_get_page+0x10b/0x2f0 - filemap_fault+0x661/0xad0 - ext4_filemap_fault+0x2c/0x40 - __do_fault+0x4d/0xf9 - handle_mm_fault+0x1080/0x1790 - -It only happens on our 1-vcpu instances, because there's no chance for -oom reaper to run to reclaim the to-be-killed process. - -Add a cond_resched() at the upper shrink_node_memcgs() to solve this -issue, this will mean that we will get a scheduling point for each memcg -in the reclaimed hierarchy without any dependency on the reclaimable -memory in that memcg thus making it more predictable. - -Suggested-by: Michal Hocko -Signed-off-by: Xunlei Pang -Signed-off-by: Andrew Morton -Acked-by: Chris Down -Acked-by: Michal Hocko -Acked-by: Johannes Weiner -Link: http://lkml.kernel.org/r/1598495549-67324-1-git-send-email-xlpang@linux.alibaba.com -Signed-off-by: Linus Torvalds -Fixes: b0dedc49a2da ("mm/vmscan.c: iterate only over charged shrinkers during memcg shrink_slab()") -Cc: stable@vger.kernel.org -Signed-off-by: Julius Hemanth Pitti -Signed-off-by: Greg Kroah-Hartman ---- - mm/vmscan.c | 8 ++++++++ - 1 file changed, 8 insertions(+) - -diff --git a/mm/vmscan.c b/mm/vmscan.c -index 749d239c62b2..8b97bc615d8c 100644 ---- a/mm/vmscan.c -+++ b/mm/vmscan.c -@@ -2619,6 +2619,14 @@ static void shrink_node_memcgs(pg_data_t *pgdat, struct scan_control *sc) - unsigned long reclaimed; - unsigned long scanned; - -+ /* -+ * This loop can become CPU-bound when target memcgs -+ * aren't eligible for reclaim - either because they -+ * don't have any reclaimable pages, or because their -+ * memory is explicitly protected. Avoid soft lockups. -+ */ -+ cond_resched(); -+ - switch (mem_cgroup_protected(target_memcg, memcg)) { - case MEMCG_PROT_MIN: - /* --- -2.17.1 - diff --git a/queue-5.4/series b/queue-5.4/series index 074bcbccb59..c129ae5ff4a 100644 --- a/queue-5.4/series +++ b/queue-5.4/series @@ -70,4 +70,3 @@ dm-dax-fix-table-reference-counts.patch mm-memory_hotplug-drain-per-cpu-pages-again-during-memory-offline.patch dm-call-proper-helper-to-determine-dax-support.patch dax-fix-compilation-for-config_dax-config_fs_dax.patch -mm-memcg-fix-memcg-reclaim-soft-lockup.patch