syzbot


INFO: task hung in blk_mq_get_tag

Status: auto-closed as invalid on 2019/05/19 02:21
Reported-by: syzbot+8b387a1474246a746023@syzkaller.appspotmail.com
First crash: 1982d, last: 1982d

Sample crash report:
b_state=0x0000012d, b_size=1024
device loop0 blocksize: 4096
__find_get_block_slow() failed. block=1, b_blocknr=4
b_state=0x0000012d, b_size=1024
device loop0 blocksize: 4096
INFO: task kworker/u4:13:5419 blocked for more than 140 seconds.
      Not tainted 4.14.81+ #6
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/u4:13   D26200  5419      2 0x80000000
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
 schedule+0x7f/0x1b0 kernel/sched/core.c:3490
 io_schedule+0x1c/0x70 kernel/sched/core.c:5097
 blk_mq_get_tag+0x3a1/0xa20 block/blk-mq-tag.c:161
 blk_mq_get_request+0x452/0x1420 block/blk-mq.c:382
 blk_mq_make_request+0x2db/0x1a60 block/blk-mq.c:1669
 generic_make_request+0x214/0x870 block/blk-core.c:2229
 submit_bio+0xa7/0x3a0 block/blk-core.c:2303
 submit_bh_wbc.isra.17+0x45f/0x5f0 fs/buffer.c:3144
 __block_write_full_page+0x4ee/0x980 fs/buffer.c:1826
 block_write_full_page+0x227/0x280 fs/buffer.c:3012
 __writepage+0x5f/0xc0 mm/page-writeback.c:2302
 write_cache_pages+0x518/0xe90 mm/page-writeback.c:2240
 generic_writepages+0xda/0x150 mm/page-writeback.c:2326
 do_writepages+0xe0/0x270 mm/page-writeback.c:2341
 __writeback_single_inode+0xd8/0x1020 fs/fs-writeback.c:1320
 writeback_sb_inodes+0x468/0xcd0 fs/fs-writeback.c:1584
 __writeback_inodes_wb+0xf8/0x1e0 fs/fs-writeback.c:1653
 wb_writeback+0x4ee/0xb90 fs/fs-writeback.c:1762
 wb_do_writeback fs/fs-writeback.c:1892 [inline]
 wb_workfn+0x1e0/0xe00 fs/fs-writeback.c:1928
 process_one_work+0x86e/0x1670 kernel/workqueue.c:2114
 worker_thread+0xdc/0x1000 kernel/workqueue.c:2248
 kthread+0x348/0x420 kernel/kthread.c:232
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:402
INFO: task blkid:17076 blocked for more than 140 seconds.
      Not tainted 4.14.81+ #6
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
blkid           D26792 17076    313 0x00000004
Call Trace:
 schedule+0x7f/0x1b0 kernel/sched/core.c:3490
 io_schedule+0x1c/0x70 kernel/sched/core.c:5097
 blk_mq_get_tag+0x3a1/0xa20 block/blk-mq-tag.c:161
 blk_mq_get_request+0x452/0x1420 block/blk-mq.c:382
 blk_mq_make_request+0x2db/0x1a60 block/blk-mq.c:1669
 generic_make_request+0x214/0x870 block/blk-core.c:2229
 submit_bio+0xa7/0x3a0 block/blk-core.c:2303
 submit_bh_wbc.isra.17+0x45f/0x5f0 fs/buffer.c:3144
 submit_bh fs/buffer.c:3150 [inline]
 block_read_full_page+0x66b/0x7c0 fs/buffer.c:2355
 generic_file_buffered_read mm/filemap.c:2130 [inline]
 generic_file_read_iter+0xa9d/0x1ab0 mm/filemap.c:2263
 blkdev_read_iter+0xfe/0x160 fs/block_dev.c:1926
 call_read_iter include/linux/fs.h:1776 [inline]
 new_sync_read fs/read_write.c:401 [inline]
 __vfs_read+0x414/0x5b0 fs/read_write.c:413
 vfs_read+0x11e/0x330 fs/read_write.c:447
 SYSC_read fs/read_write.c:577 [inline]
 SyS_read+0xc2/0x1a0 fs/read_write.c:570
 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x7f504766f310
RSP: 002b:00007ffeef70af18 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00000000080f0000 RCX: 00007f504766f310
RDX: 0000000000000040 RSI: 00000000021c5c58 RDI: 0000000000000003
RBP: 00000000021c5c30 R08: 0000000000000068 R09: 0101010101010101
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000021c5030
R13: 0000000000000040 R14: 00000000021c5080 R15: 00000000021c5c48

Showing all locks held in the system:
1 lock held by khungtaskd/23:
 #0:  (tasklist_lock){.+.+}, at: [<ffffffff908023b7>] debug_show_all_locks+0x74/0x20f kernel/locking/lockdep.c:4541
1 lock held by rsyslogd/1632:
 #0:  (&f->f_pos_lock){+.+.}, at: [<ffffffff90bbdcf2>] __fdget_pos+0xa2/0xc0 fs/file.c:768
2 locks held by getty/1760:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff9133cf30>] tty_ldisc_ref_wait+0x20/0x80 drivers/tty/tty_ldisc.c:275
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff913384af>] n_tty_read+0x1ff/0x15e0 drivers/tty/n_tty.c:2142
3 locks held by kworker/u4:13/5419:
 #0:  ("writeback"){+.+.}, at: [<ffffffff90727d04>] process_one_work+0x784/0x1670 kernel/workqueue.c:2085
 #1:  ((&(&wb->dwork)->work)){+.+.}, at: [<ffffffff90727d3c>] process_one_work+0x7bc/0x1670 kernel/workqueue.c:2089
 #2:  (&type->s_umount_key#23){++++}, at: [<ffffffff90b6358a>] trylock_super+0x1a/0xe0 fs/super.c:402

=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 23 Comm: khungtaskd Not tainted 4.14.81+ #6
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0xb9/0x11b lib/dump_stack.c:53
 nmi_cpu_backtrace.cold.0+0x47/0x85 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x121/0x146 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:138 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:196 [inline]
 watchdog+0x574/0xa70 kernel/hung_task.c:252
 kthread+0x348/0x420 kernel/kthread.c:232
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:402
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 17064 Comm: syz-executor2 Not tainted 4.14.81+ #6
task: ffff8801d6394680 task.stack: ffff8801c5878000
RIP: 0010:trace_lock_acquire include/trace/events/lock.h:13 [inline]
RIP: 0010:lock_acquire+0x221/0x380 kernel/locking/lockdep.c:3990
RSP: 0018:ffff8801c587f1c0 EFLAGS: 00000046
RAX: ffff8801d172d3d0 RBX: 0000000000000246 RCX: ffff8801d172d3d0
RDX: dffffc0000000000 RSI: 1ffff1003a2e5a7a RDI: ffff8801d6394eac
RBP: ffffffff92aceb60 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000002 R15: 0000000000000000
FS:  00007f2404b94700(0000) GS:ffff8801dba00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000792b60 CR3: 00000001c7daa004 CR4: 00000000001606b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 rcu_lock_acquire include/linux/rcupdate.h:244 [inline]
 rcu_read_lock include/linux/rcupdate.h:631 [inline]
 page_evictable+0x39/0x200 mm/vmscan.c:3967
 shrink_active_list+0x44f/0xc80 mm/vmscan.c:2027
 shrink_list mm/vmscan.c:2171 [inline]
 shrink_node_memcg+0x641/0x12e0 mm/vmscan.c:2438
 shrink_node+0x301/0xbf0 mm/vmscan.c:2630
 shrink_zones mm/vmscan.c:2812 [inline]
 do_try_to_free_pages+0x349/0xde0 mm/vmscan.c:2874
 try_to_free_pages+0x204/0x6b0 mm/vmscan.c:3080
 free_more_memory+0x8a/0xc0 fs/buffer.c:271
 __getblk_slow fs/buffer.c:1107 [inline]
 __getblk_gfp+0x533/0x720 fs/buffer.c:1382
 __bread_gfp+0x28/0x1e0 fs/buffer.c:1416
 sb_bread include/linux/buffer_head.h:307 [inline]
 read_raw_super_block fs/f2fs/super.c:2830 [inline]
 f2fs_fill_super+0x27d/0x5590 fs/f2fs/super.c:3058
 mount_bdev+0x2ab/0x370 fs/super.c:1149
 mount_fs+0x28f/0x31a fs/super.c:1255
 vfs_kern_mount.part.9+0xce/0x4a0 fs/namespace.c:1056
 vfs_kern_mount fs/namespace.c:1038 [inline]
 do_new_mount fs/namespace.c:2561 [inline]
 do_mount+0x404/0x26e0 fs/namespace.c:2891
 SYSC_mount fs/namespace.c:3107 [inline]
 SyS_mount+0xe5/0x100 fs/namespace.c:3084
 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x457569
RSP: 002b:00007f2404b93c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000457569
RDX: 0000000020000100 RSI: 00000000200000c0 RDI: 0000000020000680
RBP: 000000000072bf00 R08: 0000000020000280 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f2404b946d4
R13: 00000000004c2b0c R14: 00000000004d4260 R15: 00000000ffffffff
Code: 7d 62 02 00 0f 84 12 01 00 00 48 85 c9 0f 84 a4 00 00 00 48 ba 00 00 00 00 00 fc ff df 48 89 ce 48 89 c8 48 c1 ee 03 80 3c 16 00 <0f> 85 27 01 00 00 4c 8b 19 48 89 2c 24 48 89 c5 48 89 5c 24 08 

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/11/20 02:20 android-4.14 4e76528bd48d adf636a8 .config console log report ci-android-414-kasan-gce-root
* Struck through repros no longer work on HEAD.