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BUG: KMSAN: uninit-value in __list_add_valid+0x1a2/0x450 lib/list_debug.c:23
CPU: 1 PID: 7019 Comm: vhost-7017 Not tainted 4.17.0+ #19
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x188/0x2a0 mm/kmsan/kmsan.c:1465
 __msan_warning_32+0x70/0xc0 mm/kmsan/kmsan_instr.c:651
 __list_add_valid+0x1a2/0x450 lib/list_debug.c:23
 __list_add include/linux/list.h:60 [inline]
 list_add include/linux/list.h:79 [inline]
 account_entity_enqueue kernel/sched/fair.c:2652 [inline]
 enqueue_entity kernel/sched/fair.c:4176 [inline]
 enqueue_task_fair+0xe12/0x4490 kernel/sched/fair.c:5359
 enqueue_task kernel/sched/core.c:751 [inline]
 activate_task kernel/sched/core.c:770 [inline]
 ttwu_activate kernel/sched/core.c:1658 [inline]
 ttwu_do_activate kernel/sched/core.c:1717 [inline]
 ttwu_queue kernel/sched/core.c:1862 [inline]
 try_to_wake_up+0x162f/0x2260 kernel/sched/core.c:2075
 default_wake_function+0x92/0xb0 kernel/sched/core.c:3762
 __wake_up_common kernel/sched/wait.c:90 [inline]
 __wake_up_locked+0x21e/0x380 kernel/sched/wait.c:152
 complete+0xe8/0x180 kernel/sched/completion.c:36
 vhost_flush_work+0x3b/0x50 drivers/vhost/vhost.c:155
 vhost_worker+0x30c/0x570 drivers/vhost/vhost.c:360
 kthread+0x4db/0x6c0 kernel/kthread.c:241
 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:415

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:312 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:327 [inline]
 kmsan_internal_chain_origin+0x12b/0x210 mm/kmsan/kmsan.c:717
 __msan_chain_origin+0x69/0xc0 mm/kmsan/kmsan_instr.c:494
 __write_once_size include/linux/compiler.h:224 [inline]
 __list_add include/linux/list.h:66 [inline]
 list_add include/linux/list.h:79 [inline]
 account_entity_enqueue kernel/sched/fair.c:2652 [inline]
 enqueue_entity kernel/sched/fair.c:4176 [inline]
 enqueue_task_fair+0x2947/0x4490 kernel/sched/fair.c:5359
 enqueue_task kernel/sched/core.c:751 [inline]
 activate_task kernel/sched/core.c:770 [inline]
 ttwu_activate kernel/sched/core.c:1658 [inline]
 ttwu_do_activate kernel/sched/core.c:1717 [inline]
 ttwu_queue kernel/sched/core.c:1862 [inline]
 try_to_wake_up+0x162f/0x2260 kernel/sched/core.c:2075
 default_wake_function+0x92/0xb0 kernel/sched/core.c:3762
 autoremove_wake_function+0x54/0x320 kernel/sched/wait.c:373
 wake_page_function+0x30b/0x320 mm/filemap.c:1010
 __wake_up_common+0x45a/0xa50 kernel/sched/wait.c:90
 __wake_up_locked_key_bookmark+0x74/0x80 kernel/sched/wait.c:165
 wake_up_page_bit+0x1e8/0x4d0 mm/filemap.c:1030
 wake_up_page mm/filemap.c:1071 [inline]
 end_page_writeback+0x26b/0x2d0 mm/filemap.c:1233
 ext4_finish_bio+0x972/0xb50 fs/ext4/page-io.c:118
 ext4_end_bio+0x609/0xa70 fs/ext4/page-io.c:342
 bio_endio+0xaa3/0xc80 block/bio.c:1784
 req_bio_endio block/blk-core.c:284 [inline]
 blk_update_request+0xea8/0x1ae0 block/blk-core.c:3100
 scsi_end_request+0x114/0xb20 drivers/scsi/scsi_lib.c:676
 scsi_io_completion+0x15c5/0x2b90 drivers/scsi/scsi_lib.c:902
 scsi_finish_command+0x5f2/0x610 drivers/scsi/scsi.c:248
 scsi_softirq_done+0x4f1/0x520 drivers/scsi/scsi_lib.c:1687
 __blk_mq_complete_request+0x73f/0x9b0 block/blk-mq.c:567
 blk_mq_complete_request+0x36f/0x440 block/blk-mq.c:652
 scsi_mq_done+0x25a/0x280 drivers/scsi/scsi_lib.c:1998
 virtscsi_complete_cmd+0x94d/0xb50 drivers/scsi/virtio_scsi.c:207
 virtscsi_vq_done+0x193/0x2f0 drivers/scsi/virtio_scsi.c:223
 virtscsi_req_done+0xf3/0x130 drivers/scsi/virtio_scsi.c:238
 vring_interrupt+0x162/0x1d0 drivers/virtio/virtio_ring.c:960
 __handle_irq_event_percpu+0x3f2/0xdf0 kernel/irq/handle.c:149
 handle_irq_event_percpu kernel/irq/handle.c:189 [inline]
 handle_irq_event+0x18d/0x3d0 kernel/irq/handle.c:206
 handle_edge_irq+0x5e7/0x1230 kernel/irq/chip.c:791
 generic_handle_irq_desc include/linux/irqdesc.h:159 [inline]
 handle_irq+0x36e/0x660 arch/x86/kernel/irq_64.c:77
 do_IRQ+0x8e/0x1c0 arch/x86/kernel/irq.c:252

Local variable description: ----wait_page@wait_on_page_bit_common
Variable was created at:
 wait_on_page_bit_common+0x101/0x9f0 mm/filemap.c:1076
 wait_on_page_bit mm/filemap.c:1133 [inline]
 wait_on_page_writeback include/linux/pagemap.h:546 [inline]
 __filemap_fdatawait_range+0x3c5/0x520 mm/filemap.c:534
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