From: Liwei Song <liwei.song@xxxxxxxxxxxxx> The ACPI code allocates larger amount of memory during resume. This triggers a warning because the allocation happens with disabled interrupts. At this stage only one CPU is active so there should be no lock contention. If SLUB needs to call into the buddy allocator for more memory then it should not enable interrupts. Limit the check to system state with more CPUs and scheduling and only enable interrupts in SLUB at this stage. Signed-off-by: Liwei Song <liwei.song@xxxxxxxxxxxxx> [bigeasy: commit description, allocate_slab() hunk] Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> --- Are you okay with this Liwei? mm/slub.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/mm/slub.c b/mm/slub.c index 15c194ff16e6e..6ea1057edf1ab 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -1655,7 +1655,7 @@ static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node) enableirqs = true; #ifdef CONFIG_PREEMPT_RT - if (system_state > SYSTEM_BOOTING) + if (system_state > SYSTEM_BOOTING && system_state < SYSTEM_SUSPEND) enableirqs = true; #endif if (enableirqs) @@ -2771,7 +2771,8 @@ static __always_inline void *slab_alloc_node(struct kmem_cache *s, unsigned long tid; if (IS_ENABLED(CONFIG_PREEMPT_RT) && IS_ENABLED(CONFIG_DEBUG_ATOMIC_SLEEP)) - WARN_ON_ONCE(!preemptible() && system_state >= SYSTEM_SCHEDULING); + WARN_ON_ONCE(!preemptible() && + (system_state > SYSTEM_BOOTING && system_state < SYSTEM_SUSPEND)); s = slab_pre_alloc_hook(s, gfpflags); if (!s) @@ -3236,7 +3237,8 @@ int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size, int i; if (IS_ENABLED(CONFIG_PREEMPT_RT) && IS_ENABLED(CONFIG_DEBUG_ATOMIC_SLEEP)) - WARN_ON_ONCE(!preemptible() && system_state >= SYSTEM_SCHEDULING); + WARN_ON_ONCE(!preemptible() && + (system_state > SYSTEM_BOOTING && system_state < SYSTEM_SUSPEND)); /* memcg and kmem_cache debug support */ s = slab_pre_alloc_hook(s, flags); -- 2.26.2
