drop drm patch

[thirdparty/kernel/stable-queue.git] / releases / 3.18.3 / blk-mq-use-nr_cpu_ids-as-highest-cpu-id-count-for-hwq-cpu-map.patch

From a33c1ba2913802b6fb23e974bb2f6a4e73c8b7ce Mon Sep 17 00:00:00 2001
From: Jens Axboe <axboe@fb.com>
Date: Mon, 24 Nov 2014 15:02:42 -0700
Subject: blk-mq: use 'nr_cpu_ids' as highest CPU ID count for hwq <-> cpu map

From: Jens Axboe <axboe@fb.com>

commit a33c1ba2913802b6fb23e974bb2f6a4e73c8b7ce upstream.

We currently use num_possible_cpus(), but that breaks on sparc64 where
the CPU ID space is discontig. Use nr_cpu_ids as the highest CPU ID
instead, so we don't end up reading from invalid memory.

Signed-off-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 block/blk-mq-cpumap.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/block/blk-mq-cpumap.c
+++ b/block/blk-mq-cpumap.c
@@ -90,7 +90,7 @@ unsigned int *blk_mq_make_queue_map(stru
 	unsigned int *map;
 
 	/* If cpus are offline, map them to first hctx */
-	map = kzalloc_node(sizeof(*map) * num_possible_cpus(), GFP_KERNEL,
+	map = kzalloc_node(sizeof(*map) * nr_cpu_ids, GFP_KERNEL,
 				set->numa_node);
 	if (!map)
 		return NULL;