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floppy: fix add_disk() assumption on exit due to new developments

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After the patch titled "floppy: use blk_mq_alloc_disk and
blk_cleanup_disk" the floppy driver was modified to allocate
the blk_mq_alloc_disk() which allocates the disk with the
queue. This is further clarified later with the patch titled
"block: remove alloc_disk and alloc_disk_node". This clarifies
that:

   Most drivers should use and have been converted to use
   blk_alloc_disk and blk_mq_alloc_disk.  Only the scsi
   ULPs and dasd still allocate a disk separately from the
   request_queue so don't bother with convenience macros for
   something that should not see significant new users and
   remove these wrappers.

And then we have the patch titled, "block: hold a request_queue
reference for the lifetime of struct gendisk" which ensures
that a queue is *always* present for sure during the entire
lifetime of a disk.

In the floppy driver's case then the disk always comes with the
queue. So even if even if the queue was cleaned up on exit, putting
the disk *is* still required, and likewise, blk_cleanup_queue() on
a null queue should not happen now as disk->queue is valid from
disk allocation time on.

Automatic backport code scrapers should hopefully not cherry pick
this patch as a stable fix candidate without full due dilligence to
ensure all the work done on the block layer to make this happen is
merged first.

Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Link: https://lore.kernel.org/r/20210927220302.1073499-3-mcgrof@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Luis Chamberlain 2021-09-27 15:02:50 -07:00 committed by Jens Axboe
parent 2d4bcf7642
commit 2598a2bb35
1 changed files with 0 additions and 13 deletions
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13
drivers/block/floppy.c
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@ -4954,19 +4954,6 @@ static void __exit floppy_module_exit(void)
blk_cleanup_queue(disks[drive][i]->queue);
}
blk_mq_free_tag_set(&tag_sets[drive]);
/*
* These disks have not called add_disk(). Don't put down
* queue reference in put_disk().
*/
if (!(allowed_drive_mask & (1 << drive)) ||
fdc_state[FDC(drive)].version == FDC_NONE) {
for (i = 0; i < ARRAY_SIZE(floppy_type); i++) {
if (disks[drive][i])
disks[drive][i]->queue = NULL;
}
}
for (i = 0; i < ARRAY_SIZE(floppy_type); i++) {
if (disks[drive][i])
put_disk(disks[drive][i]);