From 57053d8c5c59562cac156513740c10b502a40968 Mon Sep 17 00:00:00 2001 From: Matias Bjorling Date: Tue, 10 Dec 2013 16:50:38 +0100 Subject: [PATCH] null_blk: mem garbage on NUMA systems during init For NUMA systems, initializing the blk-mq layer and using per node hctx. We initialize submit queues to 1, while blk-mq nr_hw_queues is initialized to the number of NUMA nodes. This makes the null_init_hctx function overwrite memory outside of what it allocated. In my case it lead to writing garbage into struct request_queue's mq_map. Signed-off-by: Matias Bjorling Cc: Jens Axboe Signed-off-by: Linus Torvalds --- drivers/block/null_blk.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/block/null_blk.c b/drivers/block/null_blk.c index ea192ec029c4..f370fc13aea5 100644 --- a/drivers/block/null_blk.c +++ b/drivers/block/null_blk.c @@ -495,23 +495,23 @@ static int null_add_dev(void) spin_lock_init(&nullb->lock); + if (queue_mode == NULL_Q_MQ && use_per_node_hctx) + submit_queues = nr_online_nodes; + if (setup_queues(nullb)) goto err; if (queue_mode == NULL_Q_MQ) { null_mq_reg.numa_node = home_node; null_mq_reg.queue_depth = hw_queue_depth; + null_mq_reg.nr_hw_queues = submit_queues; if (use_per_node_hctx) { null_mq_reg.ops->alloc_hctx = null_alloc_hctx; null_mq_reg.ops->free_hctx = null_free_hctx; - - null_mq_reg.nr_hw_queues = nr_online_nodes; } else { null_mq_reg.ops->alloc_hctx = blk_mq_alloc_single_hw_queue; null_mq_reg.ops->free_hctx = blk_mq_free_single_hw_queue; - - null_mq_reg.nr_hw_queues = submit_queues; } nullb->q = blk_mq_init_queue(&null_mq_reg, nullb);