syzbot


INFO: task hung in write_cache_pages (2)

Status: fixed on 2023/06/08 14:41
Subsystems: mm fs
[Documentation on labels]
Reported-by: syzbot+0adf31ecbba886ab504f@syzkaller.appspotmail.com
Fix commit: fb3592c41a44 migrate_pages: fix deadlock in batched migration
First crash: 535d, last: 336d
Cause bisection: introduced by (bisect log) :
commit 17bb55487988c5dac32d55a4f085e52f875f98cc
Author: Matthew Wilcox (Oracle) <willy@infradead.org>
Date: Tue May 17 22:12:25 2022 +0000

  ntfs: Remove check for PageError

Crash: WARNING: ODEBUG bug in netdev_run_todo (log)
Repro: C syz .config
  
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [mm?] INFO: task hung in write_cache_pages (2) 4 (6) 2023/03/03 05:38
Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in write_cache_pages fs mm 65 1944d 2315d 0/26 closed as dup on 2017/12/12 16:30
android-44 INFO: task hung in write_cache_pages 10 2177d 2232d 0/2 auto-closed as invalid on 2019/02/22 13:49
android-49 INFO: task hung in write_cache_pages syz 17 2185d 1825d 0/3 public: reported syz repro on 2019/04/14 09:28
upstream INFO: task hung in write_cache_pages (3) gfs2 C done done 10 96d 221d 26/26 fixed on 2024/02/21 18:23
linux-5.15 INFO: task hung in write_cache_pages 1 335d 335d 0/3 auto-obsoleted due to no activity on 2023/08/23 09:07
Last patch testing requests (2)
Created Duration User Patch Repo Result
2023/03/02 03:26 21m hdanton@sina.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 489fa31ea873 OK log
2023/03/02 02:29 16m hdanton@sina.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 489fa31ea873 report log

Sample crash report:
INFO: task kworker/u4:0:9 blocked for more than 143 seconds.
      Not tainted 6.2.0-syzkaller-10827-g489fa31ea873 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:0    state:D stack:21720 pid:9     ppid:2      flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5304 [inline]
 __schedule+0x17d8/0x4990 kernel/sched/core.c:6622
 schedule+0xc3/0x180 kernel/sched/core.c:6698
 io_schedule+0x8c/0x100 kernel/sched/core.c:8884
 folio_wait_bit_common+0x86c/0x12b0 mm/filemap.c:1301
 folio_lock include/linux/pagemap.h:952 [inline]
 write_cache_pages+0x58f/0x1450 mm/page-writeback.c:2440
 mpage_writepages+0x107/0x1d0 fs/mpage.c:653
 do_writepages+0x3a6/0x670 mm/page-writeback.c:2551
 __writeback_single_inode+0x1c4/0x15e0 fs/fs-writeback.c:1600
 writeback_sb_inodes+0x92c/0x1360 fs/fs-writeback.c:1891
 __writeback_inodes_wb+0x11b/0x260 fs/fs-writeback.c:1962
 wb_writeback+0x51c/0x1080 fs/fs-writeback.c:2067
 wb_check_background_flush fs/fs-writeback.c:2133 [inline]
 wb_do_writeback fs/fs-writeback.c:2221 [inline]
 wb_workfn+0xd80/0x1100 fs/fs-writeback.c:2248
 process_one_work+0x915/0x13a0 kernel/workqueue.c:2390
 worker_thread+0xa63/0x1210 kernel/workqueue.c:2537
 kthread+0x270/0x300 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
INFO: task kworker/u4:2:41 blocked for more than 143 seconds.
      Not tainted 6.2.0-syzkaller-10827-g489fa31ea873 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:2    state:D stack:20480 pid:41    ppid:2      flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:5)
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5304 [inline]
 __schedule+0x17d8/0x4990 kernel/sched/core.c:6622
 schedule+0xc3/0x180 kernel/sched/core.c:6698
 io_schedule+0x8c/0x100 kernel/sched/core.c:8884
 folio_wait_bit_common+0x86c/0x12b0 mm/filemap.c:1301
 folio_lock include/linux/pagemap.h:952 [inline]
 write_cache_pages+0x58f/0x1450 mm/page-writeback.c:2440
 mpage_writepages+0x107/0x1d0 fs/mpage.c:653
 do_writepages+0x3a6/0x670 mm/page-writeback.c:2551
 __writeback_single_inode+0x1c4/0x15e0 fs/fs-writeback.c:1600
 writeback_sb_inodes+0x92c/0x1360 fs/fs-writeback.c:1891
 __writeback_inodes_wb+0x11b/0x260 fs/fs-writeback.c:1962
 wb_writeback+0x51c/0x1080 fs/fs-writeback.c:2067
 wb_check_old_data_flush fs/fs-writeback.c:2167 [inline]
 wb_do_writeback fs/fs-writeback.c:2220 [inline]
 wb_workfn+0xccb/0x1100 fs/fs-writeback.c:2248
 process_one_work+0x915/0x13a0 kernel/workqueue.c:2390
 worker_thread+0xa63/0x1210 kernel/workqueue.c:2537
 kthread+0x270/0x300 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
INFO: task kworker/u4:4:75 blocked for more than 144 seconds.
      Not tainted 6.2.0-syzkaller-10827-g489fa31ea873 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:4    state:D stack:25088 pid:75    ppid:2      flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:1)
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5304 [inline]
 __schedule+0x17d8/0x4990 kernel/sched/core.c:6622
 schedule+0xc3/0x180 kernel/sched/core.c:6698
 io_schedule+0x8c/0x100 kernel/sched/core.c:8884
 folio_wait_bit_common+0x86c/0x12b0 mm/filemap.c:1301
 folio_lock include/linux/pagemap.h:952 [inline]
 write_cache_pages+0x58f/0x1450 mm/page-writeback.c:2440
 mpage_writepages+0x107/0x1d0 fs/mpage.c:653
 do_writepages+0x3a6/0x670 mm/page-writeback.c:2551
 __writeback_single_inode+0x1c4/0x15e0 fs/fs-writeback.c:1600
 writeback_sb_inodes+0x92c/0x1360 fs/fs-writeback.c:1891
 __writeback_inodes_wb+0x11b/0x260 fs/fs-writeback.c:1962
 wb_writeback+0x51c/0x1080 fs/fs-writeback.c:2067
 wb_check_old_data_flush fs/fs-writeback.c:2167 [inline]
 wb_do_writeback fs/fs-writeback.c:2220 [inline]
 wb_workfn+0xccb/0x1100 fs/fs-writeback.c:2248
 process_one_work+0x915/0x13a0 kernel/workqueue.c:2390
 worker_thread+0xa63/0x1210 kernel/workqueue.c:2537
 kthread+0x270/0x300 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
INFO: task syz-executor359:5222 blocked for more than 144 seconds.
      Not tainted 6.2.0-syzkaller-10827-g489fa31ea873 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor359 state:D stack:26576 pid:5222  ppid:5113   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5304 [inline]
 __schedule+0x17d8/0x4990 kernel/sched/core.c:6622
 schedule+0xc3/0x180 kernel/sched/core.c:6698
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6757
 rwsem_down_read_slowpath+0x5f4/0x950 kernel/locking/rwsem.c:1086
 __down_read_common+0x61/0x2c0 kernel/locking/rwsem.c:1250
 mmap_read_lock include/linux/mmap_lock.h:117 [inline]
 do_user_addr_fault arch/x86/mm/fault.c:1358 [inline]
 handle_page_fault arch/x86/mm/fault.c:1498 [inline]
 exc_page_fault+0x558/0x8a0 arch/x86/mm/fault.c:1554
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570
RIP: 0033:0x7fd6f371b888
RSP: 002b:00007ffd6fdf2398 EFLAGS: 00010206
RAX: 00007fd6f374ebd0 RBX: 00007fd6f374d1a8 RCX: 0000000000000001
RDX: 00007fd6f3688d30 RSI: 0000000000000000 RDI: 00007fd6f374ebd0
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000010
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000001 R14: 00007fd6f37543e0 R15: 0000000000000001
 </TASK>
INFO: task syz-executor359:5223 blocked for more than 144 seconds.
      Not tainted 6.2.0-syzkaller-10827-g489fa31ea873 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor359 state:D stack:24840 pid:5223  ppid:5113   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5304 [inline]
 __schedule+0x17d8/0x4990 kernel/sched/core.c:6622
 schedule+0xc3/0x180 kernel/sched/core.c:6698
 io_schedule+0x8c/0x100 kernel/sched/core.c:8884
 folio_wait_bit_common+0x86c/0x12b0 mm/filemap.c:1301
 folio_lock include/linux/pagemap.h:952 [inline]
 write_cache_pages+0x58f/0x1450 mm/page-writeback.c:2440
 mpage_writepages+0x107/0x1d0 fs/mpage.c:653
 do_writepages+0x3a6/0x670 mm/page-writeback.c:2551
 filemap_fdatawrite_wbc+0x125/0x180 mm/filemap.c:390
 __filemap_fdatawrite_range mm/filemap.c:423 [inline]
 file_write_and_wait_range+0x20f/0x300 mm/filemap.c:781
 __generic_file_fsync+0x72/0x190 fs/libfs.c:1132
 fat_file_fsync+0x7e/0x190 fs/fat/file.c:191
 generic_write_sync include/linux/fs.h:2452 [inline]
 generic_file_write_iter+0x2a1/0x310 mm/filemap.c:4090
 call_write_iter include/linux/fs.h:1851 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x7b2/0xbb0 fs/read_write.c:584
 ksys_write+0x1a0/0x2c0 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fd6f36ca719
RSP: 002b:00007fd6f36762f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fd6f374f7a0 RCX: 00007fd6f36ca719
RDX: 000000000208e24b RSI: 0000000020000080 RDI: 0000000000000004
RBP: 00007fd6f371c604 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fd6f371c0e0
R13: 0000000020000a80 R14: 0030656c69662f2e R15: 00007fd6f374f7a8
 </TASK>
INFO: task syz-executor359:5229 blocked for more than 144 seconds.
      Not tainted 6.2.0-syzkaller-10827-g489fa31ea873 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor359 state:D stack:26504 pid:5229  ppid:5113   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5304 [inline]
 __schedule+0x17d8/0x4990 kernel/sched/core.c:6622
 schedule+0xc3/0x180 kernel/sched/core.c:6698
 io_schedule+0x8c/0x100 kernel/sched/core.c:8884
 folio_wait_bit_common+0x86c/0x12b0 mm/filemap.c:1301
 folio_wait_writeback+0xec/0x1f0 mm/page-writeback.c:3127
 migrate_folio_unmap mm/migrate.c:1192 [inline]
 migrate_pages_batch mm/migrate.c:1685 [inline]
 migrate_pages+0x2d50/0x6610 mm/migrate.c:1973
 do_mbind mm/mempolicy.c:1338 [inline]
 kernel_mbind mm/mempolicy.c:1485 [inline]
 __do_sys_mbind mm/mempolicy.c:1559 [inline]
 __se_sys_mbind+0x75a/0x9c0 mm/mempolicy.c:1555
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fd6f36ca719
RSP: 002b:00007fd6eb3552e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ed
RAX: ffffffffffffffda RBX: 00007fd6f374f7b0 RCX: 00007fd6f36ca719
RDX: 0000000000000000 RSI: 0000000000800000 RDI: 0000000020001000
RBP: 00007fd6f371c604 R08: 0000000000000000 R09: 0000000000000002
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fd6f371c0e0
R13: 0000000020000a80 R14: 0030656c69662f2e R15: 00007fd6f374f7b8
 </TASK>
INFO: task syz-executor359:5296 blocked for more than 145 seconds.
      Not tainted 6.2.0-syzkaller-10827-g489fa31ea873 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor359 state:D stack:27008 pid:5296  ppid:5112   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5304 [inline]
 __schedule+0x17d8/0x4990 kernel/sched/core.c:6622
 schedule+0xc3/0x180 kernel/sched/core.c:6698
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6757
 rwsem_down_read_slowpath+0x5f4/0x950 kernel/locking/rwsem.c:1086
 __down_read_common+0x61/0x2c0 kernel/locking/rwsem.c:1250
 mmap_read_lock include/linux/mmap_lock.h:117 [inline]
 do_user_addr_fault arch/x86/mm/fault.c:1358 [inline]
 handle_page_fault arch/x86/mm/fault.c:1498 [inline]
 exc_page_fault+0x558/0x8a0 arch/x86/mm/fault.c:1554
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570
RIP: 0033:0x7fd6f371b888
RSP: 002b:00007ffd6fdf2398 EFLAGS: 00010206
RAX: 00007fd6f374ebd0 RBX: 00007fd6f374d1a8 RCX: 0000000000000001
RDX: 00007fd6f3688d30 RSI: 0000000000000000 RDI: 00007fd6f374ebd0
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000010
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000001 R14: 00007fd6f37543e0 R15: 0000000000000001
 </TASK>
INFO: task syz-executor359:5298 blocked for more than 145 seconds.
      Not tainted 6.2.0-syzkaller-10827-g489fa31ea873 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor359 state:D stack:24840 pid:5298  ppid:5112   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5304 [inline]
 __schedule+0x17d8/0x4990 kernel/sched/core.c:6622
 schedule+0xc3/0x180 kernel/sched/core.c:6698
 io_schedule+0x8c/0x100 kernel/sched/core.c:8884
 folio_wait_bit_common+0x86c/0x12b0 mm/filemap.c:1301
 folio_lock include/linux/pagemap.h:952 [inline]
 write_cache_pages+0x58f/0x1450 mm/page-writeback.c:2440
 mpage_writepages+0x107/0x1d0 fs/mpage.c:653
 do_writepages+0x3a6/0x670 mm/page-writeback.c:2551
 filemap_fdatawrite_wbc+0x125/0x180 mm/filemap.c:390
 __filemap_fdatawrite_range mm/filemap.c:423 [inline]
 file_write_and_wait_range+0x20f/0x300 mm/filemap.c:781
 __generic_file_fsync+0x72/0x190 fs/libfs.c:1132
 fat_file_fsync+0x7e/0x190 fs/fat/file.c:191
 generic_write_sync include/linux/fs.h:2452 [inline]
 generic_file_write_iter+0x2a1/0x310 mm/filemap.c:4090
 call_write_iter include/linux/fs.h:1851 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x7b2/0xbb0 fs/read_write.c:584
 ksys_write+0x1a0/0x2c0 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fd6f36ca719
RSP: 002b:00007fd6f36762f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fd6f374f7a0 RCX: 00007fd6f36ca719
RDX: 000000000208e24b RSI: 0000000020000080 RDI: 0000000000000004
RBP: 00007fd6f371c604 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fd6f371c0e0
R13: 0000000020000a80 R14: 0030656c69662f2e R15: 00007fd6f374f7a8
 </TASK>
INFO: task syz-executor359:5304 blocked for more than 145 seconds.
      Not tainted 6.2.0-syzkaller-10827-g489fa31ea873 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor359 state:D stack:26504 pid:5304  ppid:5112   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5304 [inline]
 __schedule+0x17d8/0x4990 kernel/sched/core.c:6622
 schedule+0xc3/0x180 kernel/sched/core.c:6698
 io_schedule+0x8c/0x100 kernel/sched/core.c:8884
 folio_wait_bit_common+0x86c/0x12b0 mm/filemap.c:1301
 folio_wait_writeback+0xec/0x1f0 mm/page-writeback.c:3127
 migrate_folio_unmap mm/migrate.c:1192 [inline]
 migrate_pages_batch mm/migrate.c:1685 [inline]
 migrate_pages+0x2d50/0x6610 mm/migrate.c:1973
 do_mbind mm/mempolicy.c:1338 [inline]
 kernel_mbind mm/mempolicy.c:1485 [inline]
 __do_sys_mbind mm/mempolicy.c:1559 [inline]
 __se_sys_mbind+0x75a/0x9c0 mm/mempolicy.c:1555
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fd6f36ca719
RSP: 002b:00007fd6eb3552e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ed
RAX: ffffffffffffffda RBX: 00007fd6f374f7b0 RCX: 00007fd6f36ca719
RDX: 0000000000000000 RSI: 0000000000800000 RDI: 0000000020001000
RBP: 00007fd6f371c604 R08: 0000000000000000 R09: 0000000000000002
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fd6f371c0e0
R13: 0000000020000a80 R14: 0030656c69662f2e R15: 00007fd6f374f7b8
 </TASK>
INFO: task syz-executor359:5460 blocked for more than 146 seconds.
      Not tainted 6.2.0-syzkaller-10827-g489fa31ea873 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor359 state:D stack:26520 pid:5460  ppid:5115   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5304 [inline]
 __schedule+0x17d8/0x4990 kernel/sched/core.c:6622
 schedule+0xc3/0x180 kernel/sched/core.c:6698
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6757
 rwsem_down_read_slowpath+0x5f4/0x950 kernel/locking/rwsem.c:1086
 __down_read_common+0x61/0x2c0 kernel/locking/rwsem.c:1250
 mmap_read_lock include/linux/mmap_lock.h:117 [inline]
 do_user_addr_fault arch/x86/mm/fault.c:1358 [inline]
 handle_page_fault arch/x86/mm/fault.c:1498 [inline]
 exc_page_fault+0x558/0x8a0 arch/x86/mm/fault.c:1554
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570
RIP: 0033:0x7fd6f371b888
RSP: 002b:00007ffd6fdf2398 EFLAGS: 00010206
RAX: 00007fd6f374ebd0 RBX: 00007fd6f374d1a8 RCX: 0000000000000001
RDX: 00007fd6f3688d30 RSI: 0000000000000000 RDI: 00007fd6f374ebd0
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000010
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000001 R14: 00007fd6f37543e0 R15: 0000000000000001
 </TASK>
Future hung task reports are suppressed, see sysctl kernel.hung_task_warnings

Showing all locks held in the system:
3 locks held by kworker/u4:0/9:
 #0: ffff8881451bb938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x77f/0x13a0
 #1: ffffc900000e7d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7c6/0x13a0 kernel/workqueue.c:2365
 #2: ffff88807dfe20e0 (&type->s_umount_key#43){++++}-{3:3}, at: trylock_super+0x1f/0xf0 fs/super.c:414
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8d127cf0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xd20 kernel/rcu/tasks.h:510
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8d1284f0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xd20 kernel/rcu/tasks.h:510
1 lock held by khungtaskd/28:
 #0: ffffffff8d127b20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
3 locks held by kworker/u4:2/41:
 #0: ffff8881451bb938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x77f/0x13a0
 #1: ffffc90000b27d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7c6/0x13a0 kernel/workqueue.c:2365
 #2: ffff88801d8680e0 (&type->s_umount_key#43){++++}-{3:3}, at: trylock_super+0x1f/0xf0 fs/super.c:414
3 locks held by kworker/u4:4/75:
 #0: ffff8881451bb938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x77f/0x13a0
 #1: ffffc900020efd20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7c6/0x13a0 kernel/workqueue.c:2365
 #2: ffff88802c2640e0 (&type->s_umount_key#43){++++}-{3:3}, at: trylock_super+0x1f/0xf0 fs/super.c:414
2 locks held by kworker/1:2/2494:
 #0: ffff888012472538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x77f/0x13a0
 #1: ffffc9000a86fd20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7c6/0x13a0 kernel/workqueue.c:2365
2 locks held by getty/4750:
 #0: ffff88814a0e2098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:244
 #1: ffffc900015802f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6ab/0x1db0 drivers/tty/n_tty.c:2177
1 lock held by syz-executor359/5222:
 #0: ffff88807d1df698 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock include/linux/mmap_lock.h:117 [inline]
 #0: ffff88807d1df698 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault arch/x86/mm/fault.c:1358 [inline]
 #0: ffff88807d1df698 (&mm->mmap_lock){++++}-{3:3}, at: handle_page_fault arch/x86/mm/fault.c:1498 [inline]
 #0: ffff88807d1df698 (&mm->mmap_lock){++++}-{3:3}, at: exc_page_fault+0x558/0x8a0 arch/x86/mm/fault.c:1554
2 locks held by syz-executor359/5223:
 #0: ffff888021e0f768 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x254/0x2f0 fs/file.c:1046
 #1: ffff88802c264460 (sb_writers#9){.+.+}-{0:0}, at: vfs_write+0x26d/0xbb0 fs/read_write.c:580
1 lock held by syz-executor359/5229:
 #0: ffff88807d1df698 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock include/linux/mmap_lock.h:71 [inline]
 #0: ffff88807d1df698 (&mm->mmap_lock){++++}-{3:3}, at: do_mbind mm/mempolicy.c:1312 [inline]
 #0: ffff88807d1df698 (&mm->mmap_lock){++++}-{3:3}, at: kernel_mbind mm/mempolicy.c:1485 [inline]
 #0: ffff88807d1df698 (&mm->mmap_lock){++++}-{3:3}, at: __do_sys_mbind mm/mempolicy.c:1559 [inline]
 #0: ffff88807d1df698 (&mm->mmap_lock){++++}-{3:3}, at: __se_sys_mbind+0x47d/0x9c0 mm/mempolicy.c:1555
1 lock held by syz-executor359/5296:
 #0: ffff88802cd0ae98 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock include/linux/mmap_lock.h:117 [inline]
 #0: ffff88802cd0ae98 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault arch/x86/mm/fault.c:1358 [inline]
 #0: ffff88802cd0ae98 (&mm->mmap_lock){++++}-{3:3}, at: handle_page_fault arch/x86/mm/fault.c:1498 [inline]
 #0: ffff88802cd0ae98 (&mm->mmap_lock){++++}-{3:3}, at: exc_page_fault+0x558/0x8a0 arch/x86/mm/fault.c:1554
2 locks held by syz-executor359/5298:
 #0: ffff88807e2b0fe8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x254/0x2f0 fs/file.c:1046
 #1: ffff88807dfe2460 (sb_writers#9){.+.+}-{0:0}, at: vfs_write+0x26d/0xbb0 fs/read_write.c:580
1 lock held by syz-executor359/5304:
 #0: ffff88802cd0ae98 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock include/linux/mmap_lock.h:71 [inline]
 #0: ffff88802cd0ae98 (&mm->mmap_lock){++++}-{3:3}, at: do_mbind mm/mempolicy.c:1312 [inline]
 #0: ffff88802cd0ae98 (&mm->mmap_lock){++++}-{3:3}, at: kernel_mbind mm/mempolicy.c:1485 [inline]
 #0: ffff88802cd0ae98 (&mm->mmap_lock){++++}-{3:3}, at: __do_sys_mbind mm/mempolicy.c:1559 [inline]
 #0: ffff88802cd0ae98 (&mm->mmap_lock){++++}-{3:3}, at: __se_sys_mbind+0x47d/0x9c0 mm/mempolicy.c:1555
1 lock held by syz-executor359/5460:
 #0: ffff888022485298 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock include/linux/mmap_lock.h:117 [inline]
 #0: ffff888022485298 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault arch/x86/mm/fault.c:1358 [inline]
 #0: ffff888022485298 (&mm->mmap_lock){++++}-{3:3}, at: handle_page_fault arch/x86/mm/fault.c:1498 [inline]
 #0: ffff888022485298 (&mm->mmap_lock){++++}-{3:3}, at: exc_page_fault+0x558/0x8a0 arch/x86/mm/fault.c:1554
2 locks held by syz-executor359/5461:
 #0: ffff88801da66ae8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x254/0x2f0 fs/file.c:1046
 #1: ffff888148d0a460 (sb_writers#9){.+.+}-{0:0}, at: vfs_write+0x26d/0xbb0 fs/read_write.c:580
1 lock held by syz-executor359/5467:
 #0: ffff888022485298 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock include/linux/mmap_lock.h:71 [inline]
 #0: ffff888022485298 (&mm->mmap_lock){++++}-{3:3}, at: do_mbind mm/mempolicy.c:1312 [inline]
 #0: ffff888022485298 (&mm->mmap_lock){++++}-{3:3}, at: kernel_mbind mm/mempolicy.c:1485 [inline]
 #0: ffff888022485298 (&mm->mmap_lock){++++}-{3:3}, at: __do_sys_mbind mm/mempolicy.c:1559 [inline]
 #0: ffff888022485298 (&mm->mmap_lock){++++}-{3:3}, at: __se_sys_mbind+0x47d/0x9c0 mm/mempolicy.c:1555
1 lock held by syz-executor359/5570:
 #0: ffff88807d295298 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock include/linux/mmap_lock.h:117 [inline]
 #0: ffff88807d295298 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault arch/x86/mm/fault.c:1358 [inline]
 #0: ffff88807d295298 (&mm->mmap_lock){++++}-{3:3}, at: handle_page_fault arch/x86/mm/fault.c:1498 [inline]
 #0: ffff88807d295298 (&mm->mmap_lock){++++}-{3:3}, at: exc_page_fault+0x558/0x8a0 arch/x86/mm/fault.c:1554
2 locks held by syz-executor359/5571:
 #0: ffff88807838a5e8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x254/0x2f0 fs/file.c:1046
 #1: ffff88801d868460 (sb_writers#9){.+.+}-{0:0}, at: vfs_write+0x26d/0xbb0 fs/read_write.c:580
1 lock held by syz-executor359/5575:
 #0: ffff88807d295298 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock include/linux/mmap_lock.h:71 [inline]
 #0: ffff88807d295298 (&mm->mmap_lock){++++}-{3:3}, at: do_mbind mm/mempolicy.c:1312 [inline]
 #0: ffff88807d295298 (&mm->mmap_lock){++++}-{3:3}, at: kernel_mbind mm/mempolicy.c:1485 [inline]
 #0: ffff88807d295298 (&mm->mmap_lock){++++}-{3:3}, at: __do_sys_mbind mm/mempolicy.c:1559 [inline]
 #0: ffff88807d295298 (&mm->mmap_lock){++++}-{3:3}, at: __se_sys_mbind+0x47d/0x9c0 mm/mempolicy.c:1555
1 lock held by syz-executor359/5572:
 #0: ffff88807d1dc098 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock include/linux/mmap_lock.h:117 [inline]
 #0: ffff88807d1dc098 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault arch/x86/mm/fault.c:1358 [inline]
 #0: ffff88807d1dc098 (&mm->mmap_lock){++++}-{3:3}, at: handle_page_fault arch/x86/mm/fault.c:1498 [inline]
 #0: ffff88807d1dc098 (&mm->mmap_lock){++++}-{3:3}, at: exc_page_fault+0x558/0x8a0 arch/x86/mm/fault.c:1554
2 locks held by syz-executor359/5573:
 #0: ffff888026d84d68 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x254/0x2f0 fs/file.c:1046
 #1: ffff88807b6ac460 (sb_writers#9){.+.+}-{0:0}, at: vfs_write+0x26d/0xbb0 fs/read_write.c:580
1 lock held by syz-executor359/5576:
 #0: ffff88807d1dc098 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock include/linux/mmap_lock.h:71 [inline]
 #0: ffff88807d1dc098 (&mm->mmap_lock){++++}-{3:3}, at: do_mbind mm/mempolicy.c:1312 [inline]
 #0: ffff88807d1dc098 (&mm->mmap_lock){++++}-{3:3}, at: kernel_mbind mm/mempolicy.c:1485 [inline]
 #0: ffff88807d1dc098 (&mm->mmap_lock){++++}-{3:3}, at: __do_sys_mbind mm/mempolicy.c:1559 [inline]
 #0: ffff88807d1dc098 (&mm->mmap_lock){++++}-{3:3}, at: __se_sys_mbind+0x47d/0x9c0 mm/mempolicy.c:1555
3 locks held by kworker/u4:3/5614:
 #0: ffff8881451bb938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x77f/0x13a0
 #1: ffffc90004defd20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7c6/0x13a0 kernel/workqueue.c:2365
 #2: ffff88807b6ac0e0 (&type->s_umount_key#43){++++}-{3:3}, at: trylock_super+0x1f/0xf0 fs/super.c:414
3 locks held by kworker/u4:5/6087:
 #0: ffff8881451bb938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x77f/0x13a0
 #1: ffffc900055b7d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7c6/0x13a0 kernel/workqueue.c:2365
 #2: ffff888148d0a0e0 (&type->s_umount_key#43){++++}-{3:3}, at: trylock_super+0x1f/0xf0 fs/super.c:414
1 lock held by syz-executor359/12461:
 #0: ffffffff8d12d1f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:293 [inline]
 #0: ffffffff8d12d1f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a3/0x890 kernel/rcu/tree_exp.h:989

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

NMI backtrace for cpu 0
CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.2.0-syzkaller-10827-g489fa31ea873 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/16/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x4e5/0x560 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x1b4/0x410 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
 watchdog+0x1024/0x1070 kernel/hung_task.c:379
 kthread+0x270/0x300 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 6343 Comm: kworker/u4:9 Not tainted 6.2.0-syzkaller-10827-g489fa31ea873 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/16/2023
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:rcu_sync_is_idle include/linux/rcu_sync.h:36 [inline]
RIP: 0010:percpu_up_read include/linux/percpu-rwsem.h:105 [inline]
RIP: 0010:cpus_read_unlock+0x5f/0x130 kernel/cpu.c:322
Code: 85 db 74 1b e8 c2 4f 20 00 89 c3 31 ff 89 c6 e8 87 23 39 00 85 db 74 5b e8 ce 1f 39 00 eb 05 e8 c7 1f 39 00 8b 1d 41 be a8 0b <31> ff 89 de e8 68 23 39 00 85 db 0f 85 8c 00 00 00 e8 ab 1f 39 00
RSP: 0018:ffffc90005757b70 EFLAGS: 00000293
RAX: ffffffff81538cb2 RBX: 0000000000000000 RCX: ffff888028643a80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90005757c50 R08: ffffffff81538ca9 R09: fffffbfff1ce8d2e
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffff1104779cc03 R14: 0000000000000000 R15: 1ffff92000aeaf70
FS:  0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd6fdf0bb8 CR3: 000000000cf30000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 toggle_allocation_gate+0xb5/0x250 mm/kfence/core.c:799
 process_one_work+0x915/0x13a0 kernel/workqueue.c:2390
 worker_thread+0xa63/0x1210 kernel/workqueue.c:2537
 kthread+0x270/0x300 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>

Crashes (36):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/02/26 00:26 upstream 489fa31ea873 ee50e71c .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kasan-gce-smack-root INFO: task hung in write_cache_pages
2023/03/08 05:57 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci fe15c26ee26e d2b00170 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-gce-arm64 INFO: task hung in write_cache_pages
2023/04/28 05:58 upstream 91ec4b0d11fe 70a605de .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in write_cache_pages
2023/04/22 16:10 upstream 8e41e0a57566 2b32bd34 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in write_cache_pages
2023/04/21 06:56 upstream 6a66fdd29ea1 2b32bd34 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in write_cache_pages
2023/04/10 08:44 upstream 09a9639e56c0 71147e29 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in write_cache_pages
2023/03/21 06:49 upstream 7d31677bb7b1 7939252e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in write_cache_pages
2023/03/05 06:21 upstream b01fe98d34f3 f8902b57 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in write_cache_pages
2023/03/02 17:52 upstream ee3f96b16468 f8902b57 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in write_cache_pages
2023/02/25 12:40 upstream 489fa31ea873 ee50e71c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in write_cache_pages
2023/02/24 22:42 upstream a93e884edf61 ee50e71c .config console log report info ci-upstream-kasan-gce-smack-root INFO: task hung in write_cache_pages
2023/01/25 09:02 upstream fb6e71db53f3 9dfcf09c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in write_cache_pages
2023/01/13 03:59 upstream e8f60cd7db24 96166539 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in write_cache_pages
2023/01/11 00:39 upstream 5a41237ad1d4 48bc529a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in write_cache_pages
2023/01/07 05:37 upstream a689b938df39 1dac8c7a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in write_cache_pages
2023/01/04 20:34 upstream 69b41ac87e4a 1dac8c7a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in write_cache_pages
2022/12/28 10:51 upstream 1b929c02afd3 44712fbc .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in write_cache_pages
2022/12/08 13:11 upstream 479174d402bc d88f3abb .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in write_cache_pages
2022/11/27 12:46 upstream faf68e3523c2 f4470a7b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in write_cache_pages
2022/11/25 05:39 upstream c3eb11fbb826 74a66371 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in write_cache_pages
2022/11/21 10:58 upstream eb7081409f94 5bb70014 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in write_cache_pages
2022/11/20 14:13 upstream fe24a97cf254 5bb70014 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in write_cache_pages
2022/11/20 06:30 upstream fe24a97cf254 5bb70014 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in write_cache_pages
2022/11/20 04:40 upstream fe24a97cf254 5bb70014 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in write_cache_pages
2022/11/18 12:17 upstream 84368d882b96 5bb70014 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in write_cache_pages
2022/11/15 19:22 upstream e01d50cbd6ee 97de9cfc .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in write_cache_pages
2022/11/14 04:35 upstream af7a05689189 7ba4d859 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in write_cache_pages
2022/11/03 06:27 upstream b229b6ca5abb 7a2ebf95 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in write_cache_pages
2022/10/25 06:33 upstream 337a0a0b63f1 45645420 .config console log report info [disk image] [vmlinux] ci2-upstream-fs INFO: task hung in write_cache_pages
2023/02/25 18:26 upstream 489fa31ea873 ee50e71c .config console log report info ci-upstream-kasan-gce-386 INFO: task hung in write_cache_pages
2023/05/11 19:32 linux-next aabe491169be adb9a3cd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in write_cache_pages
2023/04/17 15:18 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 1f5b16c51aef c6ec7083 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 INFO: task hung in write_cache_pages
2023/03/16 05:28 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci fe15c26ee26e 18b58603 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 INFO: task hung in write_cache_pages
2023/03/10 04:57 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci fe15c26ee26e f08b59ac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 INFO: task hung in write_cache_pages
2023/03/08 01:30 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci fe15c26ee26e d2b00170 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 INFO: task hung in write_cache_pages
2023/03/07 12:33 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci fe15c26ee26e ffaa5c55 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 INFO: task hung in write_cache_pages
* Struck through repros no longer work on HEAD.