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lib/sbitmap: define swap_lock as raw_spinlock_t

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When called from sbitmap_queue_get(), sbitmap_deferred_clear() may be run
with preempt disabled. In RT kernel, spin_lock() can sleep, then warning
of "BUG: sleeping function called from invalid context" can be triggered.

Fix it by replacing it with raw_spin_lock.

Cc: Yang Yang <yang.yang@vivo.com>
Fixes: 72d04bdcf3 ("sbitmap: fix io hung due to race on sbitmap_word::cleared")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Yang Yang <yang.yang@vivo.com>
Link: https://lore.kernel.org/r/20240919021709.511329-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Ming Lei 2024-09-19 10:17:09 +08:00 committed by Jens Axboe
parent 9ba5dcc722
commit 65f666c620
2 changed files with 3 additions and 3 deletions
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2
include/linux/sbitmap.h
View File

@ -40,7 +40,7 @@ struct sbitmap_word {
/**
* @swap_lock: serializes simultaneous updates of ->word and ->cleared
*/
spinlock_t swap_lock;
raw_spinlock_t swap_lock;
} ____cacheline_aligned_in_smp;
/**

4
lib/sbitmap.c
View File

@ -65,7 +65,7 @@ static inline bool sbitmap_deferred_clear(struct sbitmap_word *map,
{
unsigned long mask, word_mask;
guard(spinlock_irqsave)(&map->swap_lock);
guard(raw_spinlock_irqsave)(&map->swap_lock);
if (!map->cleared) {
if (depth == 0)
@ -136,7 +136,7 @@ int sbitmap_init_node(struct sbitmap *sb, unsigned int depth, int shift,
}
for (i = 0; i < sb->map_nr; i++)
spin_lock_init(&sb->map[i].swap_lock);
raw_spin_lock_init(&sb->map[i].swap_lock);
return 0;
}