| Message ID | 20230914152139.100822-1-hannes@cmpxchg.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | mm: memcontrol: fix GFP_NOFS recursion in memory.high enforcement | expand |
On Thu, Sep 14, 2023 at 8:21 AM Johannes Weiner <hannes@cmpxchg.org> wrote: > > Breno and Josef report a deadlock scenario from cgroup reclaim > re-entering the filesystem: > > [ 361.546690] ====================================================== > [ 361.559210] WARNING: possible circular locking dependency detected > [ 361.571703] 6.5.0-0_fbk700_debug_rc0_kbuilder_13159_gbf787a128001 #1 Tainted: G S E > [ 361.589704] ------------------------------------------------------ > [ 361.602277] find/9315 is trying to acquire lock: > [ 361.611625] ffff88837ba140c0 (&delayed_node->mutex){+.+.}-{4:4}, at: __btrfs_release_delayed_node+0x68/0x4f0 > [ 361.631437] > [ 361.631437] but task is already holding lock: > [ 361.643243] ffff8881765b8678 (btrfs-tree-01){++++}-{4:4}, at: btrfs_tree_read_lock+0x1e/0x40 > > [ 362.904457] mutex_lock_nested+0x1c/0x30 > [ 362.912414] __btrfs_release_delayed_node+0x68/0x4f0 > [ 362.922460] btrfs_evict_inode+0x301/0x770 > [ 362.982726] evict+0x17c/0x380 > [ 362.988944] prune_icache_sb+0x100/0x1d0 > [ 363.005559] super_cache_scan+0x1f8/0x260 > [ 363.013695] do_shrink_slab+0x2a2/0x540 > [ 363.021489] shrink_slab_memcg+0x237/0x3d0 > [ 363.050606] shrink_slab+0xa7/0x240 > [ 363.083382] shrink_node_memcgs+0x262/0x3b0 > [ 363.091870] shrink_node+0x1a4/0x720 > [ 363.099150] shrink_zones+0x1f6/0x5d0 > [ 363.148798] do_try_to_free_pages+0x19b/0x5e0 > [ 363.157633] try_to_free_mem_cgroup_pages+0x266/0x370 > [ 363.190575] reclaim_high+0x16f/0x1f0 > [ 363.208409] mem_cgroup_handle_over_high+0x10b/0x270 > [ 363.246678] try_charge_memcg+0xaf2/0xc70 > [ 363.304151] charge_memcg+0xf0/0x350 > [ 363.320070] __mem_cgroup_charge+0x28/0x40 > [ 363.328371] __filemap_add_folio+0x870/0xd50 > [ 363.371303] filemap_add_folio+0xdd/0x310 > [ 363.399696] __filemap_get_folio+0x2fc/0x7d0 > [ 363.419086] pagecache_get_page+0xe/0x30 > [ 363.427048] alloc_extent_buffer+0x1cd/0x6a0 > [ 363.435704] read_tree_block+0x43/0xc0 > [ 363.443316] read_block_for_search+0x361/0x510 > [ 363.466690] btrfs_search_slot+0xc8c/0x1520 > > This is caused by the mem_cgroup_handle_over_high() not respecting the > gfp_mask of the allocation context. We used to only call this function > on resume to userspace, where no locks were held. But c9afe31ec443 > ("memcg: synchronously enforce memory.high for large overcharges") > added a call from the allocation context without considering the gfp. > > Reported-by: Breno Leitao <leitao@debian.org> > Reported-by: Josef Bacik <josef@toxicpanda.com> > Fixes: c9afe31ec443 ("memcg: synchronously enforce memory.high for large overcharges") > Cc: stable@vger.kernel.org # 5.17+ > Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Shakeel Butt <shakeelb@google.com>
On Thu 14-09-23 11:21:39, Johannes Weiner wrote: > Breno and Josef report a deadlock scenario from cgroup reclaim > re-entering the filesystem: > > [ 361.546690] ====================================================== > [ 361.559210] WARNING: possible circular locking dependency detected > [ 361.571703] 6.5.0-0_fbk700_debug_rc0_kbuilder_13159_gbf787a128001 #1 Tainted: G S E > [ 361.589704] ------------------------------------------------------ > [ 361.602277] find/9315 is trying to acquire lock: > [ 361.611625] ffff88837ba140c0 (&delayed_node->mutex){+.+.}-{4:4}, at: __btrfs_release_delayed_node+0x68/0x4f0 > [ 361.631437] > [ 361.631437] but task is already holding lock: > [ 361.643243] ffff8881765b8678 (btrfs-tree-01){++++}-{4:4}, at: btrfs_tree_read_lock+0x1e/0x40 > > [ 362.904457] mutex_lock_nested+0x1c/0x30 > [ 362.912414] __btrfs_release_delayed_node+0x68/0x4f0 > [ 362.922460] btrfs_evict_inode+0x301/0x770 > [ 362.982726] evict+0x17c/0x380 > [ 362.988944] prune_icache_sb+0x100/0x1d0 > [ 363.005559] super_cache_scan+0x1f8/0x260 > [ 363.013695] do_shrink_slab+0x2a2/0x540 > [ 363.021489] shrink_slab_memcg+0x237/0x3d0 > [ 363.050606] shrink_slab+0xa7/0x240 > [ 363.083382] shrink_node_memcgs+0x262/0x3b0 > [ 363.091870] shrink_node+0x1a4/0x720 > [ 363.099150] shrink_zones+0x1f6/0x5d0 > [ 363.148798] do_try_to_free_pages+0x19b/0x5e0 > [ 363.157633] try_to_free_mem_cgroup_pages+0x266/0x370 > [ 363.190575] reclaim_high+0x16f/0x1f0 > [ 363.208409] mem_cgroup_handle_over_high+0x10b/0x270 > [ 363.246678] try_charge_memcg+0xaf2/0xc70 > [ 363.304151] charge_memcg+0xf0/0x350 > [ 363.320070] __mem_cgroup_charge+0x28/0x40 > [ 363.328371] __filemap_add_folio+0x870/0xd50 > [ 363.371303] filemap_add_folio+0xdd/0x310 > [ 363.399696] __filemap_get_folio+0x2fc/0x7d0 > [ 363.419086] pagecache_get_page+0xe/0x30 > [ 363.427048] alloc_extent_buffer+0x1cd/0x6a0 > [ 363.435704] read_tree_block+0x43/0xc0 > [ 363.443316] read_block_for_search+0x361/0x510 > [ 363.466690] btrfs_search_slot+0xc8c/0x1520 > > This is caused by the mem_cgroup_handle_over_high() not respecting the > gfp_mask of the allocation context. We used to only call this function > on resume to userspace, where no locks were held. But c9afe31ec443 > ("memcg: synchronously enforce memory.high for large overcharges") > added a call from the allocation context without considering the gfp. > > Reported-by: Breno Leitao <leitao@debian.org> > Reported-by: Josef Bacik <josef@toxicpanda.com> > Fixes: c9afe31ec443 ("memcg: synchronously enforce memory.high for large overcharges") > Cc: stable@vger.kernel.org # 5.17+ > Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Michal Hocko <mhocko@suse.com> Thanks!
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index ab94ad4597d0..e4e24da16d2c 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -920,7 +920,7 @@ unsigned long mem_cgroup_get_zone_lru_size(struct lruvec *lruvec, return READ_ONCE(mz->lru_zone_size[zone_idx][lru]); } -void mem_cgroup_handle_over_high(void); +void mem_cgroup_handle_over_high(gfp_t gfp_mask); unsigned long mem_cgroup_get_max(struct mem_cgroup *memcg); @@ -1458,7 +1458,7 @@ static inline void mem_cgroup_unlock_pages(void) rcu_read_unlock(); } -static inline void mem_cgroup_handle_over_high(void) +static inline void mem_cgroup_handle_over_high(gfp_t gfp_mask) { } diff --git a/include/linux/resume_user_mode.h b/include/linux/resume_user_mode.h index 285189454449..f8f3e958e9cf 100644 --- a/include/linux/resume_user_mode.h +++ b/include/linux/resume_user_mode.h @@ -55,7 +55,7 @@ static inline void resume_user_mode_work(struct pt_regs *regs) } #endif - mem_cgroup_handle_over_high(); + mem_cgroup_handle_over_high(GFP_KERNEL); blkcg_maybe_throttle_current(); rseq_handle_notify_resume(NULL, regs); diff --git a/mm/memcontrol.c b/mm/memcontrol.c index a4d3282493b6..d13dde2f8b56 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2555,7 +2555,7 @@ static unsigned long calculate_high_delay(struct mem_cgroup *memcg, * Scheduled by try_charge() to be executed from the userland return path * and reclaims memory over the high limit. */ -void mem_cgroup_handle_over_high(void) +void mem_cgroup_handle_over_high(gfp_t gfp_mask) { unsigned long penalty_jiffies; unsigned long pflags; @@ -2583,7 +2583,7 @@ void mem_cgroup_handle_over_high(void) */ nr_reclaimed = reclaim_high(memcg, in_retry ? SWAP_CLUSTER_MAX : nr_pages, - GFP_KERNEL); + gfp_mask); /* * memory.high is breached and reclaim is unable to keep up. Throttle @@ -2819,7 +2819,7 @@ static int try_charge_memcg(struct mem_cgroup *memcg, gfp_t gfp_mask, if (current->memcg_nr_pages_over_high > MEMCG_CHARGE_BATCH && !(current->flags & PF_MEMALLOC) && gfpflags_allow_blocking(gfp_mask)) { - mem_cgroup_handle_over_high(); + mem_cgroup_handle_over_high(gfp_mask); } return 0; }
Breno and Josef report a deadlock scenario from cgroup reclaim re-entering the filesystem: [ 361.546690] ====================================================== [ 361.559210] WARNING: possible circular locking dependency detected [ 361.571703] 6.5.0-0_fbk700_debug_rc0_kbuilder_13159_gbf787a128001 #1 Tainted: G S E [ 361.589704] ------------------------------------------------------ [ 361.602277] find/9315 is trying to acquire lock: [ 361.611625] ffff88837ba140c0 (&delayed_node->mutex){+.+.}-{4:4}, at: __btrfs_release_delayed_node+0x68/0x4f0 [ 361.631437] [ 361.631437] but task is already holding lock: [ 361.643243] ffff8881765b8678 (btrfs-tree-01){++++}-{4:4}, at: btrfs_tree_read_lock+0x1e/0x40 [ 362.904457] mutex_lock_nested+0x1c/0x30 [ 362.912414] __btrfs_release_delayed_node+0x68/0x4f0 [ 362.922460] btrfs_evict_inode+0x301/0x770 [ 362.982726] evict+0x17c/0x380 [ 362.988944] prune_icache_sb+0x100/0x1d0 [ 363.005559] super_cache_scan+0x1f8/0x260 [ 363.013695] do_shrink_slab+0x2a2/0x540 [ 363.021489] shrink_slab_memcg+0x237/0x3d0 [ 363.050606] shrink_slab+0xa7/0x240 [ 363.083382] shrink_node_memcgs+0x262/0x3b0 [ 363.091870] shrink_node+0x1a4/0x720 [ 363.099150] shrink_zones+0x1f6/0x5d0 [ 363.148798] do_try_to_free_pages+0x19b/0x5e0 [ 363.157633] try_to_free_mem_cgroup_pages+0x266/0x370 [ 363.190575] reclaim_high+0x16f/0x1f0 [ 363.208409] mem_cgroup_handle_over_high+0x10b/0x270 [ 363.246678] try_charge_memcg+0xaf2/0xc70 [ 363.304151] charge_memcg+0xf0/0x350 [ 363.320070] __mem_cgroup_charge+0x28/0x40 [ 363.328371] __filemap_add_folio+0x870/0xd50 [ 363.371303] filemap_add_folio+0xdd/0x310 [ 363.399696] __filemap_get_folio+0x2fc/0x7d0 [ 363.419086] pagecache_get_page+0xe/0x30 [ 363.427048] alloc_extent_buffer+0x1cd/0x6a0 [ 363.435704] read_tree_block+0x43/0xc0 [ 363.443316] read_block_for_search+0x361/0x510 [ 363.466690] btrfs_search_slot+0xc8c/0x1520 This is caused by the mem_cgroup_handle_over_high() not respecting the gfp_mask of the allocation context. We used to only call this function on resume to userspace, where no locks were held. But c9afe31ec443 ("memcg: synchronously enforce memory.high for large overcharges") added a call from the allocation context without considering the gfp. Reported-by: Breno Leitao <leitao@debian.org> Reported-by: Josef Bacik <josef@toxicpanda.com> Fixes: c9afe31ec443 ("memcg: synchronously enforce memory.high for large overcharges") Cc: stable@vger.kernel.org # 5.17+ Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> --- include/linux/memcontrol.h | 4 ++-- include/linux/resume_user_mode.h | 2 +- mm/memcontrol.c | 6 +++--- 3 files changed, 6 insertions(+), 6 deletions(-)