diff options
| author | Christoph Hellwig <hch@lst.de> | 2021-05-21 07:50:54 +0200 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2021-06-01 07:42:23 -0600 |
| commit | 958229a7c55f219b1cff99f939dabbc1b6ba7161 (patch) | |
| tree | 95e14b94cb882656a3337f78f19102f305c1b515 | |
| parent | 0d1feb72ffd8578f6f167ca15b2096c276c1f6df (diff) | |
block: add a flag to make put_disk on partially initalized disks safer
Add a flag to indicate that __device_add_disk did grab a queue reference
so that disk_release only drops it if we actually had it. This sort
out one of the major pitfals with partially initialized gendisk that
a lot of drivers did get wrong or still do.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20210521055116.1053587-5-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | block/genhd.c | 7 | ||||
| -rw-r--r-- | include/linux/genhd.h | 1 |
2 files changed, 6 insertions, 2 deletions
diff --git a/block/genhd.c b/block/genhd.c index 9fa734cb9cbd..c826db33a73e 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -539,7 +539,10 @@ static void __device_add_disk(struct device *parent, struct gendisk *disk, * Take an extra ref on queue which will be put on disk_release() * so that it sticks around as long as @disk is there. */ - WARN_ON_ONCE(!blk_get_queue(disk->queue)); + if (blk_get_queue(disk->queue)) + set_bit(GD_QUEUE_REF, &disk->state); + else + WARN_ON_ONCE(1); disk_add_events(disk); blk_integrity_add(disk); @@ -1107,7 +1110,7 @@ static void disk_release(struct device *dev) kfree(disk->random); xa_destroy(&disk->part_tbl); bdput(disk->part0); - if (disk->queue) + if (test_bit(GD_QUEUE_REF, &disk->state) && disk->queue) blk_put_queue(disk->queue); kfree(disk); } diff --git a/include/linux/genhd.h b/include/linux/genhd.h index 6fc26f7bdf71..4d3ee8b6b297 100644 --- a/include/linux/genhd.h +++ b/include/linux/genhd.h @@ -153,6 +153,7 @@ struct gendisk { unsigned long state; #define GD_NEED_PART_SCAN 0 #define GD_READ_ONLY 1 +#define GD_QUEUE_REF 2 struct kobject *slave_dir; struct timer_rand_state *random; |