blk-mq: cleanup after blk_mq_init_rq_map failures
In blk-mq.c blk_mq_alloc_tag_set, if:
set->tags = kmalloc_node()
succeeds, but one of the blk_mq_init_rq_map() calls fails,
goto out_unwind;
needs to free set->tags so the caller is not obligated
to do so. None of the current callers (null_blk,
virtio_blk, virtio_blk, or the forthcoming scsi-mq)
do so.
set->tags needs to be set to NULL after doing so,
so other tag cleanup logic doesn't try to free
a stale pointer later. Also set it to NULL
in blk_mq_free_tag_set.
Tested with error injection on the forthcoming
scsi-mq + hpsa combination.
Signed-off-by: Robert Elliott <elliott@hp.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 4aac826..f9b85e8 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1982,6 +1982,8 @@
out_unwind:
while (--i >= 0)
blk_mq_free_rq_map(set, set->tags[i], i);
+ kfree(set->tags);
+ set->tags = NULL;
out:
return -ENOMEM;
}
@@ -1997,6 +1999,7 @@
}
kfree(set->tags);
+ set->tags = NULL;
}
EXPORT_SYMBOL(blk_mq_free_tag_set);