diff options
Diffstat (limited to 'mm/page_alloc.c')
| -rw-r--r-- | mm/page_alloc.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 1cffd4e1f..4553cc848 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -5425,7 +5425,21 @@ static void __build_all_zonelists(void *data) int nid; int __maybe_unused cpu; pg_data_t *self = data; + unsigned long flags; + /* + * Explicitly disable this CPU's interrupts before taking seqlock + * to prevent any IRQ handler from calling into the page allocator + * (e.g. GFP_ATOMIC) that could hit zonelist_iter_begin and livelock. + */ + local_irq_save(flags); + /* + * Explicitly disable this CPU's synchronous printk() before taking + * seqlock to prevent any printk() from trying to hold port->lock, for + * tty_insert_flip_string_and_push_buffer() on other CPU might be + * calling kmalloc(GFP_ATOMIC | __GFP_NOWARN) with port->lock held. + */ + printk_deferred_enter(); write_seqlock(&zonelist_update_seq); #ifdef CONFIG_NUMA @@ -5460,6 +5474,8 @@ static void __build_all_zonelists(void *data) } write_sequnlock(&zonelist_update_seq); + printk_deferred_exit(); + local_irq_restore(flags); } static noinline void __init |