From: Coly Li colyli@suse.de
[ Upstream commit ba54d4d4d2844c234f1b4692bd8c9e0f833c8a54 ]
Using GFP_NOIO flag to call scribble_alloc() from resize_chunk() does not have the expected behavior. kvmalloc_array() inside scribble_alloc() which receives the GFP_NOIO flag will eventually call kmalloc_node() to allocate physically continuous pages.
Now we have memalloc scope APIs in mddev_suspend()/mddev_resume() to prevent memory reclaim I/Os during raid array suspend context, calling to kvmalloc_array() with GFP_KERNEL flag may avoid deadlock of recursive I/O as expected.
This patch removes the useless gfp flags from parameters list of scribble_alloc(), and call kvmalloc_array() with GFP_KERNEL flag. The incorrect GFP_NOIO flag does not exist anymore.
Fixes: b330e6a49dc3 ("md: convert to kvmalloc") Suggested-by: Michal Hocko mhocko@suse.com Signed-off-by: Coly Li colyli@suse.de Signed-off-by: Song Liu songliubraving@fb.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/md/raid5.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-)
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 36cd7c2fbf40..a3cbc9f4fec1 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -2228,14 +2228,19 @@ static int grow_stripes(struct r5conf *conf, int num) * of the P and Q blocks. */ static int scribble_alloc(struct raid5_percpu *percpu, - int num, int cnt, gfp_t flags) + int num, int cnt) { size_t obj_size = sizeof(struct page *) * (num+2) + sizeof(addr_conv_t) * (num+2); void *scribble;
- scribble = kvmalloc_array(cnt, obj_size, flags); + /* + * If here is in raid array suspend context, it is in memalloc noio + * context as well, there is no potential recursive memory reclaim + * I/Os with the GFP_KERNEL flag. + */ + scribble = kvmalloc_array(cnt, obj_size, GFP_KERNEL); if (!scribble) return -ENOMEM;
@@ -2267,8 +2272,7 @@ static int resize_chunks(struct r5conf *conf, int new_disks, int new_sectors)
percpu = per_cpu_ptr(conf->percpu, cpu); err = scribble_alloc(percpu, new_disks, - new_sectors / STRIPE_SECTORS, - GFP_NOIO); + new_sectors / STRIPE_SECTORS); if (err) break; } @@ -6765,8 +6769,7 @@ static int alloc_scratch_buffer(struct r5conf *conf, struct raid5_percpu *percpu conf->previous_raid_disks), max(conf->chunk_sectors, conf->prev_chunk_sectors) - / STRIPE_SECTORS, - GFP_KERNEL)) { + / STRIPE_SECTORS)) { free_scratch_buffer(conf, percpu); return -ENOMEM; }