diff options
| author | Akinobu Mita <akinobu.mita@gmail.com> | 2015-09-26 17:09:19 (GMT) |
|---|---|---|
| committer | Luis Henriques <luis.henriques@canonical.com> | 2015-11-10 10:01:26 (GMT) |
| commit | babbf7db6d39d809ae132394f1196463ef118ca0 (patch) | |
| tree | 17094caafa15f94e6804a6f7412cf97ebfac707b | |
| parent | 0666ca3c1b79d0c7f104f719b07d8e859f2045ce (diff) | |
blk-mq: avoid setting hctx->tags->cpumask before allocation
BugLink: http://bugs.launchpad.net/bugs/1509886
commit 1356aae08338f1c19ce1c67bf8c543a267688fc3 upstream.
When unmapped hw queue is remapped after CPU topology is changed,
hctx->tags->cpumask has to be set after hctx->tags is setup in
blk_mq_map_swqueue(), otherwise it causes null pointer dereference.
Fixes: f26cdc8536 ("blk-mq: Shared tag enhancements")
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Ming Lei <tom.leiming@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Brad Figg <brad.figg@canonical.com>
| -rw-r--r-- | block/blk-mq.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/block/blk-mq.c b/block/blk-mq.c index 176262e..c699026 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1807,7 +1807,6 @@ static void blk_mq_map_swqueue(struct request_queue *q) hctx = q->mq_ops->map_queue(q, i); cpumask_set_cpu(i, hctx->cpumask); - cpumask_set_cpu(i, hctx->tags->cpumask); ctx->index_hw = hctx->nr_ctx; hctx->ctxs[hctx->nr_ctx++] = ctx; } @@ -1847,6 +1846,14 @@ static void blk_mq_map_swqueue(struct request_queue *q) hctx->next_cpu = cpumask_first(hctx->cpumask); hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH; } + + queue_for_each_ctx(q, ctx, i) { + if (!cpu_online(i)) + continue; + + hctx = q->mq_ops->map_queue(q, i); + cpumask_set_cpu(i, hctx->tags->cpumask); + } } static void blk_mq_update_tag_set_depth(struct blk_mq_tag_set *set) |