syzbot


INFO: task hung in do_page_fault

Status: auto-obsoleted due to no activity on 2023/08/23 09:07
Reported-by: syzbot+e2f63dcc72399ef03ed2@syzkaller.appspotmail.com
First crash: 566d, last: 566d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in do_page_fault serial arm 12 503d 634d 0/28 auto-obsoleted due to no activity on 2023/10/05 00:47

Sample crash report:
INFO: task syz-executor.1:7268 blocked for more than 143 seconds.
      Not tainted 5.15.110-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.1  state:D stack:    0 pid: 7268 ppid:  4016 flags:0x00000001
Call trace:
 __switch_to+0x308/0x5e8 arch/arm64/kernel/process.c:518
 context_switch kernel/sched/core.c:5026 [inline]
 __schedule+0xf10/0x1e38 kernel/sched/core.c:6372
 schedule+0x11c/0x1c8 kernel/sched/core.c:6455
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6514
 rwsem_down_read_slowpath+0x5b0/0x988 kernel/locking/rwsem.c:1047
 __down_read_common+0x6c/0x2dc kernel/locking/rwsem.c:1231
 __down_read kernel/locking/rwsem.c:1244 [inline]
 down_read+0xc8/0x11c kernel/locking/rwsem.c:1490
 mmap_read_lock include/linux/mmap_lock.h:117 [inline]
 do_page_fault+0x66c/0xb60 arch/arm64/mm/fault.c:590
 do_mem_abort+0x70/0x1d8 arch/arm64/mm/fault.c:819
 el0_da+0x94/0x20c arch/arm64/kernel/entry-common.c:482
 el0t_64_sync_handler+0xc0/0xe4 arch/arm64/kernel/entry-common.c:617
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
INFO: task syz-executor.1:7270 blocked for more than 143 seconds.
      Not tainted 5.15.110-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.1  state:D stack:    0 pid: 7270 ppid:  4016 flags:0x00000009
Call trace:
 __switch_to+0x308/0x5e8 arch/arm64/kernel/process.c:518
 context_switch kernel/sched/core.c:5026 [inline]
 __schedule+0xf10/0x1e38 kernel/sched/core.c:6372
 schedule+0x11c/0x1c8 kernel/sched/core.c:6455
 io_schedule+0x8c/0x194 kernel/sched/core.c:8472
 wait_on_page_bit_common+0x6fc/0xc14 mm/filemap.c:1356
 wait_on_page_bit+0x58/0x68 mm/filemap.c:1417
 wait_on_page_writeback+0x70/0x408 mm/page-writeback.c:2887
 __unmap_and_move mm/migrate.c:1010 [inline]
 unmap_and_move mm/migrate.c:1214 [inline]
 migrate_pages+0x172c/0x3280 mm/migrate.c:1491
 do_mbind mm/mempolicy.c:1325 [inline]
 kernel_mbind mm/mempolicy.c:1472 [inline]
 __do_sys_mbind mm/mempolicy.c:1479 [inline]
 __se_sys_mbind mm/mempolicy.c:1475 [inline]
 __arm64_sys_mbind+0x1004/0x13ac mm/mempolicy.c:1475
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:596
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:614
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
INFO: task syz-executor.1:7292 blocked for more than 143 seconds.
      Not tainted 5.15.110-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.1  state:D stack:    0 pid: 7292 ppid:  4016 flags:0x00000009
Call trace:
 __switch_to+0x308/0x5e8 arch/arm64/kernel/process.c:518
 context_switch kernel/sched/core.c:5026 [inline]
 __schedule+0xf10/0x1e38 kernel/sched/core.c:6372
 schedule+0x11c/0x1c8 kernel/sched/core.c:6455
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6514
 rwsem_down_read_slowpath+0x5b0/0x988 kernel/locking/rwsem.c:1047
 __down_read_common+0x6c/0x2dc kernel/locking/rwsem.c:1231
 __down_read kernel/locking/rwsem.c:1244 [inline]
 down_read+0xc8/0x11c kernel/locking/rwsem.c:1490
 mmap_read_lock include/linux/mmap_lock.h:117 [inline]
 do_page_fault+0x66c/0xb60 arch/arm64/mm/fault.c:590
 do_mem_abort+0x70/0x1d8 arch/arm64/mm/fault.c:819
 el1_abort+0x3c/0x5c arch/arm64/kernel/entry-common.c:358
 el1h_64_sync_handler+0x5c/0x98 arch/arm64/kernel/entry-common.c:409
 el1h_64_sync+0x78/0x7c arch/arm64/kernel/entry.S:579
 __uaccess_mask_ptr arch/arm64/include/asm/uaccess.h:247 [inline]
 mm_release+0x1c4/0x318 kernel/fork.c:1405
 exit_mm_release+0x30/0x40 kernel/fork.c:1423
 exit_mm+0xa4/0x70c kernel/exit.c:486
 do_exit+0x4f0/0x2134 kernel/exit.c:859
 do_group_exit+0x110/0x268 kernel/exit.c:994
 get_signal+0x634/0x1550 kernel/signal.c:2889
 do_signal arch/arm64/kernel/signal.c:890 [inline]
 do_notify_resume+0x3d0/0x32b8 arch/arm64/kernel/signal.c:943
 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:133 [inline]
 exit_to_user_mode arch/arm64/kernel/entry-common.c:138 [inline]
 el0_svc+0xfc/0x1f0 arch/arm64/kernel/entry-common.c:597
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:614
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
INFO: task segctord:7291 blocked for more than 143 seconds.
      Not tainted 5.15.110-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:segctord        state:D stack:    0 pid: 7291 ppid:     2 flags:0x00000008
Call trace:
 __switch_to+0x308/0x5e8 arch/arm64/kernel/process.c:518
 context_switch kernel/sched/core.c:5026 [inline]
 __schedule+0xf10/0x1e38 kernel/sched/core.c:6372
 schedule+0x11c/0x1c8 kernel/sched/core.c:6455
 io_schedule+0x8c/0x194 kernel/sched/core.c:8472
 wait_on_page_bit_common+0x6fc/0xc14 mm/filemap.c:1356
 __lock_page+0x8c/0xa8 mm/filemap.c:1648
 lock_page include/linux/pagemap.h:625 [inline]
 nilfs_lookup_dirty_data_buffers+0x2c4/0x888 fs/nilfs2/segment.c:727
 nilfs_segctor_scan_file+0x1e4/0xd9c fs/nilfs2/segment.c:1073
 nilfs_segctor_collect_blocks fs/nilfs2/segment.c:1195 [inline]
 nilfs_segctor_collect fs/nilfs2/segment.c:1522 [inline]
 nilfs_segctor_do_construct+0x1790/0x67cc fs/nilfs2/segment.c:2065
 nilfs_segctor_construct+0x110/0x768 fs/nilfs2/segment.c:2401
 nilfs_segctor_thread_construct fs/nilfs2/segment.c:2509 [inline]
 nilfs_segctor_thread+0x3c8/0xe94 fs/nilfs2/segment.c:2592
 kthread+0x37c/0x45c kernel/kthread.c:319
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffff800014aa1960 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:268
2 locks held by kworker/u4:2/148:
2 locks held by getty/3726:
 #0: ffff0000d4470098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x40/0x50 drivers/tty/tty_ldsem.c:340
 #1: ffff80001a28b2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x414/0x1200 drivers/tty/n_tty.c:2147
1 lock held by syz-executor.1/7268:
 #0: ffff0000c7f21818 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock include/linux/mmap_lock.h:117 [inline]
 #0: ffff0000c7f21818 (&mm->mmap_lock){++++}-{3:3}, at: do_page_fault+0x66c/0xb60 arch/arm64/mm/fault.c:590
1 lock held by syz-executor.1/7270:
 #0: ffff0000c7f21818 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock include/linux/mmap_lock.h:71 [inline]
 #0: ffff0000c7f21818 (&mm->mmap_lock){++++}-{3:3}, at: do_mbind mm/mempolicy.c:1299 [inline]
 #0: ffff0000c7f21818 (&mm->mmap_lock){++++}-{3:3}, at: kernel_mbind mm/mempolicy.c:1472 [inline]
 #0: ffff0000c7f21818 (&mm->mmap_lock){++++}-{3:3}, at: __do_sys_mbind mm/mempolicy.c:1479 [inline]
 #0: ffff0000c7f21818 (&mm->mmap_lock){++++}-{3:3}, at: __se_sys_mbind mm/mempolicy.c:1475 [inline]
 #0: ffff0000c7f21818 (&mm->mmap_lock){++++}-{3:3}, at: __arm64_sys_mbind+0x5c4/0x13ac mm/mempolicy.c:1475
1 lock held by syz-executor.1/7292:
 #0: ffff0000c7f21818 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock include/linux/mmap_lock.h:117 [inline]
 #0: ffff0000c7f21818 (&mm->mmap_lock){++++}-{3:3}, at: do_page_fault+0x66c/0xb60 arch/arm64/mm/fault.c:590
1 lock held by segctord/7291:
 #0: ffff0000d9eea2a0 (&nilfs->ns_segctor_sem){++++}-{3:3}, at: nilfs_transaction_lock+0x150/0x3d0 fs/nilfs2/segment.c:357
3 locks held by udevd/9327:
1 lock held by syz-executor.4/9634:
 #0: ffff000108ac40e0 (&type->s_umount_key#26/1){+.+.}-{3:3}, at: alloc_super+0x1b8/0x844 fs/super.c:229
3 locks held by syz-executor.2/9639:
2 locks held by syz-executor.3/9638:
 #0: ffff0001b4830d18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:475 [inline]
 #0: ffff0001b4830d18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1326 [inline]
 #0: ffff0001b4830d18 (&rq->__lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1621 [inline]
 #0: ffff0001b4830d18 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0x328/0x1e38 kernel/sched/core.c:6286
 #1: ffff0001b481ec48 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x438/0x66c kernel/sched/psi.c:891

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


Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/05/04 16:43 linux-5.15.y 8a7f2a5c5aa1 518a39a6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 INFO: task hung in do_page_fault
* Struck through repros no longer work on HEAD.