INFO: The task syz.1.2091:11243 has been waiting for writeback completion for more than 1 seconds.
INFO: The task syz.1.2091:11243 has been waiting for writeback completion for more than 1 seconds.
INFO: The task syz.1.2091:11243 has been waiting for writeback completion for more than 1 seconds.
FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 0
CPU: 0 UID: 0 PID: 11243 Comm: syz.1.2091 Not tainted syzkaller #0 PREEMPT 
Hardware name: linux,dummy-virt (DT)
Call trace:
 dump_backtrace arch/arm64/kernel/stacktrace.c:498 [inline] (C)
 show_stack+0x18/0x24 arch/arm64/kernel/stacktrace.c:499 (C)
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x60/0x80 lib/dump_stack.c:120
 dump_stack+0x18/0x24 lib/dump_stack.c:129
 fail_dump lib/fault-inject.c:73 [inline]
 should_fail_ex+0x1e0/0x238 lib/fault-inject.c:174
 should_failslab+0x54/0x80 mm/failslab.c:46
 slab_pre_alloc_hook mm/slub.c:4906 [inline]
 slab_alloc_node mm/slub.c:5239 [inline]
 __do_kmalloc_node mm/slub.c:5656 [inline]
 __kmalloc_noprof+0xb4/0x600 mm/slub.c:5669
 kmalloc_noprof include/linux/slab.h:961 [inline]
 alloc_indirect_split drivers/virtio/virtio_ring.c:496 [inline]
 virtqueue_add_split drivers/virtio/virtio_ring.c:568 [inline]
 virtqueue_add drivers/virtio/virtio_ring.c:2281 [inline]
 virtqueue_add_sgs+0x218/0x660 drivers/virtio/virtio_ring.c:2319
 virtblk_add_req+0xb4/0x124 drivers/block/virtio_blk.c:157
 virtblk_add_req_batch+0x54/0x104 drivers/block/virtio_blk.c:486
 virtio_queue_rqs+0xf4/0x16c drivers/block/virtio_blk.c:522
 __blk_mq_flush_list block/blk-mq.c:2848 [inline]
 __blk_mq_flush_list block/blk-mq.c:2844 [inline]
 blk_mq_dispatch_queue_requests.isra.0+0x100/0x118 block/blk-mq.c:2893
 blk_mq_flush_plug_list+0x90/0x178 block/blk-mq.c:2981
 __blk_flush_plug+0xf8/0x15c block/blk-core.c:1225
 blk_finish_plug block/blk-core.c:1252 [inline]
 blk_finish_plug+0x38/0x58 block/blk-core.c:1249
 blkdev_writepages+0x90/0xc8 block/fops.c:488
 do_writepages+0xa8/0x17c mm/page-writeback.c:2598
 filemap_writeback+0xd4/0xfc mm/filemap.c:387
 filemap_fdatawrite_range mm/filemap.c:412 [inline]
 filemap_fdatawrite+0x20/0x34 mm/filemap.c:418
 sync_bdevs+0x174/0x180 block/bdev.c:1317
 ksys_sync+0x6c/0xc0 fs/sync.c:105
 __arm64_sys_sync+0x10/0x20 fs/sync.c:113
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x48/0x104 arch/arm64/kernel/syscall.c:49
 el0_svc_common.constprop.0+0x40/0xe0 arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x1c/0x28 arch/arm64/kernel/syscall.c:151
 el0_svc+0x34/0x124 arch/arm64/kernel/entry-common.c:724
 el0t_64_sync_handler+0xa0/0xf0 arch/arm64/kernel/entry-common.c:743
 el0t_64_sync+0x1a4/0x1a8 arch/arm64/kernel/entry.S:596