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author | Ming Lei <ming.lei@redhat.com> | 2018-01-06 16:27:40 +0800 |
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committer | Jens Axboe <axboe@kernel.dk> | 2018-01-06 09:25:36 -0700 |
commit | fb350e0ad99359768e1e80b4784692031ec340e4 (patch) | |
tree | 25d87e34b68ada63eb442c6269b031f037011520 /arch/arc | |
parent | 7d4901a90d02500c8011472a060f9b2e60e6e605 (diff) | |
download | linux-fb350e0ad99359768e1e80b4784692031ec340e4.tar.gz linux-fb350e0ad99359768e1e80b4784692031ec340e4.tar.bz2 linux-fb350e0ad99359768e1e80b4784692031ec340e4.zip |
blk-mq: fix race between updating nr_hw_queues and switching io sched
In both elevator_switch_mq() and blk_mq_update_nr_hw_queues(), sched tags
can be allocated, and q->nr_hw_queue is used, and race is inevitable, for
example: blk_mq_init_sched() may trigger use-after-free on hctx, which is
freed in blk_mq_realloc_hw_ctxs() when nr_hw_queues is decreased.
This patch fixes the race be holding q->sysfs_lock.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reported-by: Yi Zhang <yi.zhang@redhat.com>
Tested-by: Yi Zhang <yi.zhang@redhat.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'arch/arc')
0 files changed, 0 insertions, 0 deletions