WARNING will be triggered when __kmalloc greater than 1 page with GFP_NOFAIL. On system with a large number of cpus, init_blk_queue_async_dispatch() may attempt to allocate memory larger than 1 page, causing the WARING:

------------[ cut here ]------------ WARNING: CPU: 4 PID: 1 at mm/page_alloc.c:3485 get_page_from_freelist+0x115c/0x1224 Modules linked in: CPU: 4 PID: 1 Comm: swapper/0 Not tainted 5.10.0-212.0.0.112.oe2203sp4.aarch64 #1 Call trace: get_page_from_freelist+0x115c/0x1224 __alloc_pages+0x254/0x11f0 alloc_page_interleave+0x24/0xb0 alloc_pages+0xf0/0x16c kmalloc_order+0x38/0x1c0 kmalloc_order_trace+0x34/0x130 __kmalloc+0x524/0x680 init_blk_queue_async_dispatch+0xe8/0x160 blk_dev_init+0xa8/0xd0 genhd_device_init+0x64/0xb4 do_one_initcall+0x50/0x2a0 do_initcall_level+0xe4/0x110 do_initcalls+0x80/0xb8 kernel_init_freeable+0x1c8/0x254 kernel_init+0x1c/0x144 ret_from_fork+0x10/0x18 ---[ end trace 5fed5af9086c724c ]---

Fix it by removing flag GFP_NOFAIL and panic kernel if allocation fails.

Signed-off-by: Li Nan linan122@huawei.com --- block/blk-core.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/block/blk-core.c b/block/blk-core.c index e3e2659d0673..95f7d796482b 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -285,7 +285,8 @@ static void init_blk_queue_async_dispatch(void)

init_waitqueue_head(&ctl->wait); ctl->bios = kmalloc_array(nr_cpu_ids, sizeof(struct async_bio), - GFP_KERNEL | __GFP_NOFAIL); + GFP_KERNEL); + BUG_ON(!ctl->bios); for (i = 0; i < nr_cpu_ids; ++i) { bio_list_init(&ctl->bios[i].list); spin_lock_init(&ctl->bios[i].lock);