syzbot


INFO: task hung in blkdev_flush_mapping (2)

Status: upstream: reported on 2026/03/18 19:16
Reported-by: syzbot+d22c70692c881c0b7af3@syzkaller.appspotmail.com
First crash: 50d, last: 7d16h
Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 INFO: task hung in blkdev_flush_mapping 1 1 772d 772d 0/3 auto-obsoleted due to no activity on 2024/07/04 14:18
linux-6.6 INFO: task hung in blkdev_flush_mapping 1 1 285d 285d 0/2 auto-obsoleted due to no activity on 2025/11/03 12:40
linux-6.1 INFO: task hung in blkdev_flush_mapping origin:upstream 1 C error 20 396d 970d 0/3 upstream: reported C repro on 2023/09/09 22:51
upstream INFO: task hung in blkdev_flush_mapping block 1 C unreliable error 74 22d 871d 0/29 upstream: reported C repro on 2023/12/18 10:31

Sample crash report:
INFO: task udevd:5758 blocked for more than 142 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd           state:D stack:24168 pid:5758  ppid:5138   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0x1553/0x45a0 kernel/sched/core.c:6700
 schedule+0xbd/0x170 kernel/sched/core.c:6774
 io_schedule+0x80/0xd0 kernel/sched/core.c:9023
 folio_wait_bit_common+0x714/0xfa0 mm/filemap.c:1329
 __filemap_get_folio+0xbc/0xbb0 mm/filemap.c:1910
 truncate_inode_pages_range+0x46b/0xfb0 mm/truncate.c:401
 kill_bdev block/bdev.c:76 [inline]
 blkdev_flush_mapping+0x132/0x290 block/bdev.c:649
 blkdev_put_whole block/bdev.c:680 [inline]
 blkdev_put+0x498/0x760 block/bdev.c:958
 blkdev_release+0x84/0x90 block/fops.c:604
 __fput+0x234/0x970 fs/file_table.c:384
 task_work_run+0x1d4/0x260 kernel/task_work.c:245
 exit_task_work include/linux/task_work.h:43 [inline]
 do_exit+0x95a/0x2460 kernel/exit.c:883
 do_group_exit+0x21b/0x2d0 kernel/exit.c:1024
 get_signal+0x12fc/0x13f0 kernel/signal.c:2902
 arch_do_signal_or_restart+0xc2/0x800 arch/x86/kernel/signal.c:310
 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
 do_syscall_64+0x61/0xa0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fb4c04a7407
RSP: 002b:00007fffacba1740 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: 0000000000000008 RBX: 00007fb4c0ca7880 RCX: 00007fb4c04a7407
RDX: 00000000000a0800 RSI: 00005590c8ed1f80 RDI: ffffffffffffff9c
RBP: 00005590c8eb5910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00005590c8ec8e20
R13: 00005590c8ecd410 R14: 0000000000000000 R15: 00005590c8ec8e20
 </TASK>
INFO: task udevd:5761 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd           state:D stack:24328 pid:5761  ppid:5138   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0x1553/0x45a0 kernel/sched/core.c:6700
 schedule+0xbd/0x170 kernel/sched/core.c:6774
 io_schedule+0x80/0xd0 kernel/sched/core.c:9023
 folio_wait_bit_common+0x714/0xfa0 mm/filemap.c:1329
 folio_put_wait_locked mm/filemap.c:1493 [inline]
 do_read_cache_folio+0x1c0/0x7d0 mm/filemap.c:3791
 read_mapping_folio include/linux/pagemap.h:898 [inline]
 read_part_sector+0xd2/0x340 block/partitions/core.c:718
 adfspart_check_POWERTEC+0x93/0xed0 block/partitions/acorn.c:454
 check_partition block/partitions/core.c:138 [inline]
 blk_add_partitions block/partitions/core.c:600 [inline]
 bdev_disk_changed+0x740/0x1420 block/partitions/core.c:689
 blkdev_get_whole+0x30d/0x390 block/bdev.c:672
 blkdev_get_by_dev+0x279/0x600 block/bdev.c:814
 blkdev_open+0x152/0x360 block/fops.c:589
 do_dentry_open+0x8c6/0x1500 fs/open.c:929
 do_open fs/namei.c:3640 [inline]
 path_openat+0x27f1/0x3230 fs/namei.c:3797
 do_filp_open+0x1f5/0x430 fs/namei.c:3824
 do_sys_openat2+0x134/0x1d0 fs/open.c:1421
 do_sys_open fs/open.c:1436 [inline]
 __do_sys_openat fs/open.c:1452 [inline]
 __se_sys_openat fs/open.c:1447 [inline]
 __x64_sys_openat+0x139/0x160 fs/open.c:1447
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fb4c04a7407
RSP: 002b:00007fffacba1740 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fb4c0ca7880 RCX: 00007fb4c04a7407
RDX: 00000000000a0800 RSI: 00005590c8ecef60 RDI: ffffffffffffff9c
RBP: 00005590c8eb5910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00005590c8ecf320
R13: 00005590c8ecd410 R14: 0000000000000000 R15: 00005590c8ecf320
 </TASK>
INFO: task udevd:5762 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd           state:D stack:23528 pid:5762  ppid:5138   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0x1553/0x45a0 kernel/sched/core.c:6700
 schedule+0xbd/0x170 kernel/sched/core.c:6774
 io_schedule+0x80/0xd0 kernel/sched/core.c:9023
 folio_wait_bit_common+0x714/0xfa0 mm/filemap.c:1329
 folio_put_wait_locked mm/filemap.c:1493 [inline]
 do_read_cache_folio+0x1c0/0x7d0 mm/filemap.c:3791
 read_mapping_folio include/linux/pagemap.h:898 [inline]
 read_part_sector+0xd2/0x340 block/partitions/core.c:718
 adfspart_check_POWERTEC+0x93/0xed0 block/partitions/acorn.c:454
 check_partition block/partitions/core.c:138 [inline]
 blk_add_partitions block/partitions/core.c:600 [inline]
 bdev_disk_changed+0x740/0x1420 block/partitions/core.c:689
 blkdev_get_whole+0x30d/0x390 block/bdev.c:672
 blkdev_get_by_dev+0x279/0x600 block/bdev.c:814
 blkdev_open+0x152/0x360 block/fops.c:589
 do_dentry_open+0x8c6/0x1500 fs/open.c:929
 do_open fs/namei.c:3640 [inline]
 path_openat+0x27f1/0x3230 fs/namei.c:3797
 do_filp_open+0x1f5/0x430 fs/namei.c:3824
 do_sys_openat2+0x134/0x1d0 fs/open.c:1421
 do_sys_open fs/open.c:1436 [inline]
 __do_sys_openat fs/open.c:1452 [inline]
 __se_sys_openat fs/open.c:1447 [inline]
 __x64_sys_openat+0x139/0x160 fs/open.c:1447
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fb4c04a7407
RSP: 002b:00007fffacba1740 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fb4c0ca7880 RCX: 00007fb4c04a7407
RDX: 00000000000a0800 RSI: 00005590c8ee1a40 RDI: ffffffffffffff9c
RBP: 00005590c8eb5910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00005590c8ed89d0
R13: 00005590c8ecd410 R14: 0000000000000000 R15: 00005590c8ed89d0
 </TASK>
INFO: task udevd:6158 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd           state:D stack:23592 pid:6158  ppid:5138   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0x1553/0x45a0 kernel/sched/core.c:6700
 schedule+0xbd/0x170 kernel/sched/core.c:6774
 io_schedule+0x80/0xd0 kernel/sched/core.c:9023
 folio_wait_bit_common+0x714/0xfa0 mm/filemap.c:1329
 folio_put_wait_locked mm/filemap.c:1493 [inline]
 do_read_cache_folio+0x1c0/0x7d0 mm/filemap.c:3791
 read_mapping_folio include/linux/pagemap.h:898 [inline]
 read_part_sector+0xd2/0x340 block/partitions/core.c:718
 adfspart_check_POWERTEC+0x93/0xed0 block/partitions/acorn.c:454
 check_partition block/partitions/core.c:138 [inline]
 blk_add_partitions block/partitions/core.c:600 [inline]
 bdev_disk_changed+0x740/0x1420 block/partitions/core.c:689
 blkdev_get_whole+0x30d/0x390 block/bdev.c:672
 blkdev_get_by_dev+0x279/0x600 block/bdev.c:814
 blkdev_open+0x152/0x360 block/fops.c:589
 do_dentry_open+0x8c6/0x1500 fs/open.c:929
 do_open fs/namei.c:3640 [inline]
 path_openat+0x27f1/0x3230 fs/namei.c:3797
 do_filp_open+0x1f5/0x430 fs/namei.c:3824
 do_sys_openat2+0x134/0x1d0 fs/open.c:1421
 do_sys_open fs/open.c:1436 [inline]
 __do_sys_openat fs/open.c:1452 [inline]
 __se_sys_openat fs/open.c:1447 [inline]
 __x64_sys_openat+0x139/0x160 fs/open.c:1447
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fb4c04a7407
RSP: 002b:00007fffacba1740 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fb4c0ca7880 RCX: 00007fb4c04a7407
RDX: 00000000000a0800 RSI: 00005590c8ec6900 RDI: ffffffffffffff9c
RBP: 00005590c8eb5910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00005590c8ecf320
R13: 00005590c8ecd410 R14: 0000000000000000 R15: 00005590c8ecf320
 </TASK>
INFO: task udevd:7839 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd           state:D stack:24584 pid:7839  ppid:5138   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0x1553/0x45a0 kernel/sched/core.c:6700
 schedule+0xbd/0x170 kernel/sched/core.c:6774
 io_schedule+0x80/0xd0 kernel/sched/core.c:9023
 folio_wait_bit_common+0x714/0xfa0 mm/filemap.c:1329
 folio_put_wait_locked mm/filemap.c:1493 [inline]
 do_read_cache_folio+0x1c0/0x7d0 mm/filemap.c:3791
 read_mapping_folio include/linux/pagemap.h:898 [inline]
 read_part_sector+0xd2/0x340 block/partitions/core.c:718
 adfspart_check_POWERTEC+0x93/0xed0 block/partitions/acorn.c:454
 check_partition block/partitions/core.c:138 [inline]
 blk_add_partitions block/partitions/core.c:600 [inline]
 bdev_disk_changed+0x740/0x1420 block/partitions/core.c:689
 blkdev_get_whole+0x30d/0x390 block/bdev.c:672
 blkdev_get_by_dev+0x279/0x600 block/bdev.c:814
 blkdev_open+0x152/0x360 block/fops.c:589
 do_dentry_open+0x8c6/0x1500 fs/open.c:929
 do_open fs/namei.c:3640 [inline]
 path_openat+0x27f1/0x3230 fs/namei.c:3797
 do_filp_open+0x1f5/0x430 fs/namei.c:3824
 do_sys_openat2+0x134/0x1d0 fs/open.c:1421
 do_sys_open fs/open.c:1436 [inline]
 __do_sys_openat fs/open.c:1452 [inline]
 __se_sys_openat fs/open.c:1447 [inline]
 __x64_sys_openat+0x139/0x160 fs/open.c:1447
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fb4c04a7407
RSP: 002b:00007fffacba1740 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fb4c0ca7880 RCX: 00007fb4c04a7407
RDX: 00000000000a0800 RSI: 00005590c8eb6620 RDI: ffffffffffffff9c
RBP: 00005590c8eb5910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00005590c8ec8e20
R13: 00005590c8ecd410 R14: 0000000000000000 R15: 00005590c8ec8e20
 </TASK>
INFO: task udevd:7865 blocked for more than 145 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd           state:D stack:24552 pid:7865  ppid:5138   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0x1553/0x45a0 kernel/sched/core.c:6700
 schedule+0xbd/0x170 kernel/sched/core.c:6774
 io_schedule+0x80/0xd0 kernel/sched/core.c:9023
 folio_wait_bit_common+0x714/0xfa0 mm/filemap.c:1329
 folio_put_wait_locked mm/filemap.c:1493 [inline]
 do_read_cache_folio+0x1c0/0x7d0 mm/filemap.c:3791
 read_mapping_folio include/linux/pagemap.h:898 [inline]
 read_part_sector+0xd2/0x340 block/partitions/core.c:718
 adfspart_check_POWERTEC+0x93/0xed0 block/partitions/acorn.c:454
 check_partition block/partitions/core.c:138 [inline]
 blk_add_partitions block/partitions/core.c:600 [inline]
 bdev_disk_changed+0x740/0x1420 block/partitions/core.c:689
 blkdev_get_whole+0x30d/0x390 block/bdev.c:672
 blkdev_get_by_dev+0x279/0x600 block/bdev.c:814
 blkdev_open+0x152/0x360 block/fops.c:589
 do_dentry_open+0x8c6/0x1500 fs/open.c:929
 do_open fs/namei.c:3640 [inline]
 path_openat+0x27f1/0x3230 fs/namei.c:3797
 do_filp_open+0x1f5/0x430 fs/namei.c:3824
 do_sys_openat2+0x134/0x1d0 fs/open.c:1421
 do_sys_open fs/open.c:1436 [inline]
 __do_sys_openat fs/open.c:1452 [inline]
 __se_sys_openat fs/open.c:1447 [inline]
 __x64_sys_openat+0x139/0x160 fs/open.c:1447
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fb4c04a7407
RSP: 002b:00007fffacba1740 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fb4c0ca7880 RCX: 00007fb4c04a7407
RDX: 00000000000a0800 RSI: 00005590c8ed9680 RDI: ffffffffffffff9c
RBP: 00005590c8eb5910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00005590c8ed2f10
R13: 00005590c8ecd410 R14: 0000000000000000 R15: 00005590c8ed2f10
 </TASK>
INFO: task udevd:8361 blocked for more than 145 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd           state:D stack:24424 pid:8361  ppid:5138   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0x1553/0x45a0 kernel/sched/core.c:6700
 schedule+0xbd/0x170 kernel/sched/core.c:6774
 io_schedule+0x80/0xd0 kernel/sched/core.c:9023
 folio_wait_bit_common+0x714/0xfa0 mm/filemap.c:1329
 folio_put_wait_locked mm/filemap.c:1493 [inline]
 do_read_cache_folio+0x1c0/0x7d0 mm/filemap.c:3791
 read_mapping_folio include/linux/pagemap.h:898 [inline]
 read_part_sector+0xd2/0x340 block/partitions/core.c:718
 adfspart_check_POWERTEC+0x93/0xed0 block/partitions/acorn.c:454
 check_partition block/partitions/core.c:138 [inline]
 blk_add_partitions block/partitions/core.c:600 [inline]
 bdev_disk_changed+0x740/0x1420 block/partitions/core.c:689
 blkdev_get_whole+0x30d/0x390 block/bdev.c:672
 blkdev_get_by_dev+0x279/0x600 block/bdev.c:814
 blkdev_open+0x152/0x360 block/fops.c:589
 do_dentry_open+0x8c6/0x1500 fs/open.c:929
 do_open fs/namei.c:3640 [inline]
 path_openat+0x27f1/0x3230 fs/namei.c:3797
 do_filp_open+0x1f5/0x430 fs/namei.c:3824
 do_sys_openat2+0x134/0x1d0 fs/open.c:1421
 do_sys_open fs/open.c:1436 [inline]
 __do_sys_openat fs/open.c:1452 [inline]
 __se_sys_openat fs/open.c:1447 [inline]
 __x64_sys_openat+0x139/0x160 fs/open.c:1447
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fb4c04a7407
RSP: 002b:00007fffacba1740 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fb4c0ca7880 RCX: 00007fb4c04a7407
RDX: 00000000000a0800 RSI: 00005590c8ec1860 RDI: ffffffffffffff9c
RBP: 00005590c8eb5910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00005590c8ec9ba0
R13: 00005590c8ecd410 R14: 0000000000000000 R15: 00005590c8ec9ba0
 </TASK>
INFO: task udevd:8524 blocked for more than 146 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd           state:D stack:24968 pid:8524  ppid:5138   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0x1553/0x45a0 kernel/sched/core.c:6700
 schedule+0xbd/0x170 kernel/sched/core.c:6774
 io_schedule+0x80/0xd0 kernel/sched/core.c:9023
 folio_wait_bit_common+0x714/0xfa0 mm/filemap.c:1329
 folio_put_wait_locked mm/filemap.c:1493 [inline]
 do_read_cache_folio+0x1c0/0x7d0 mm/filemap.c:3791
 read_mapping_folio include/linux/pagemap.h:898 [inline]
 read_part_sector+0xd2/0x340 block/partitions/core.c:718
 adfspart_check_POWERTEC+0x93/0xed0 block/partitions/acorn.c:454
 check_partition block/partitions/core.c:138 [inline]
 blk_add_partitions block/partitions/core.c:600 [inline]
 bdev_disk_changed+0x740/0x1420 block/partitions/core.c:689
 blkdev_get_whole+0x30d/0x390 block/bdev.c:672
 blkdev_get_by_dev+0x279/0x600 block/bdev.c:814
 blkdev_open+0x152/0x360 block/fops.c:589
 do_dentry_open+0x8c6/0x1500 fs/open.c:929
 do_open fs/namei.c:3640 [inline]
 path_openat+0x27f1/0x3230 fs/namei.c:3797
 do_filp_open+0x1f5/0x430 fs/namei.c:3824
 do_sys_openat2+0x134/0x1d0 fs/open.c:1421
 do_sys_open fs/open.c:1436 [inline]
 __do_sys_openat fs/open.c:1452 [inline]
 __se_sys_openat fs/open.c:1447 [inline]
 __x64_sys_openat+0x139/0x160 fs/open.c:1447
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fb4c04a7407
RSP: 002b:00007fffacb9c410 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fb4c0ca7880 RCX: 00007fb4c04a7407
RDX: 0000000000080000 RSI: 00005590c8fa1e60 RDI: ffffffffffffff9c
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00005590c101f95f
R13: 00005590c1030660 R14: 0000000000000000 R15: 00000000ffffffff
 </TASK>
INFO: task udevd:8525 blocked for more than 146 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd           state:D stack:24968 pid:8525  ppid:5138   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0x1553/0x45a0 kernel/sched/core.c:6700
 schedule+0xbd/0x170 kernel/sched/core.c:6774
 io_schedule+0x80/0xd0 kernel/sched/core.c:9023
 folio_wait_bit_common+0x714/0xfa0 mm/filemap.c:1329
 folio_put_wait_locked mm/filemap.c:1493 [inline]
 do_read_cache_folio+0x1c0/0x7d0 mm/filemap.c:3791
 read_mapping_folio include/linux/pagemap.h:898 [inline]
 read_part_sector+0xd2/0x340 block/partitions/core.c:718
 adfspart_check_POWERTEC+0x93/0xed0 block/partitions/acorn.c:454
 check_partition block/partitions/core.c:138 [inline]
 blk_add_partitions block/partitions/core.c:600 [inline]
 bdev_disk_changed+0x740/0x1420 block/partitions/core.c:689
 blkdev_get_whole+0x30d/0x390 block/bdev.c:672
 blkdev_get_by_dev+0x279/0x600 block/bdev.c:814
 blkdev_open+0x152/0x360 block/fops.c:589
 do_dentry_open+0x8c6/0x1500 fs/open.c:929
 do_open fs/namei.c:3640 [inline]
 path_openat+0x27f1/0x3230 fs/namei.c:3797
 do_filp_open+0x1f5/0x430 fs/namei.c:3824
 do_sys_openat2+0x134/0x1d0 fs/open.c:1421
 do_sys_open fs/open.c:1436 [inline]
 __do_sys_openat fs/open.c:1452 [inline]
 __se_sys_openat fs/open.c:1447 [inline]
 __x64_sys_openat+0x139/0x160 fs/open.c:1447
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fb4c04a7407
RSP: 002b:00007fffacba1740 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fb4c0ca7880 RCX: 00007fb4c04a7407
RDX: 00000000000a0800 RSI: 00005590c8eb6520 RDI: ffffffffffffff9c
RBP: 00005590c8eb5910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00005590c8ec9ba0
R13: 00005590c8ecd410 R14: 0000000000000000 R15: 00005590c8ec9ba0
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/29:
 #0: ffffffff8d1320e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
 #0: ffffffff8d1320e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
 #0: ffffffff8d1320e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
2 locks held by getty/5530:
 #0: ffff8880209500a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000326e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x433/0x1390 drivers/tty/n_tty.c:2217
1 lock held by udevd/5758:
 #0: ffff88802226f4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xff/0x760 block/bdev.c:944
1 lock held by udevd/5761:
 #0: ffff8880229954c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x121/0x600 block/bdev.c:805
1 lock held by udevd/5762:
 #0: ffff8880222484c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x121/0x600 block/bdev.c:805
1 lock held by udevd/6158:
 #0: ffff88802226a4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x121/0x600 block/bdev.c:805
3 locks held by kworker/u4:16/6815:
1 lock held by udevd/7839:
 #0: ffff8880228bb4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x121/0x600 block/bdev.c:805
1 lock held by udevd/7865:
 #0: ffff8881407f14c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x121/0x600 block/bdev.c:805
1 lock held by udevd/8361:
 #0: ffff888022b0b4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x121/0x600 block/bdev.c:805
1 lock held by udevd/8524:
 #0: ffff88802e0e84c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x121/0x600 block/bdev.c:805
1 lock held by udevd/8525:
 #0: ffff88805eef14c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x121/0x600 block/bdev.c:805

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

NMI backtrace for cpu 0
CPU: 0 PID: 29 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
 watchdog+0xf3d/0xf80 kernel/hung_task.c:379
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 6815 Comm: kworker/u4:16 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:unwind_next_frame+0x604/0x2970 arch/x86/kernel/unwind_orc.c:495
Code: 00 fc ff df 48 c7 c0 f8 91 97 8e 49 29 c4 48 c7 c0 44 b8 08 8f 48 8b 6c 24 10 49 c1 fc 02 4b 8d 1c 64 48 01 db 48 01 c3 74 77 <e8> 37 e4 4b 00 4c 8b 24 24 4c 8d 73 04 4c 8d 7b 05 4c 89 f0 48 c1
RSP: 0018:ffffc900195b74f8 EFLAGS: 00000286
RAX: ffffffff8f0caa06 RBX: ffffffff8f0caa7e RCX: ffff888021f30000
RDX: 0000000000000000 RSI: ffffffff81310bf7 RDI: ffffffff81310bed
RBP: ffffc900195b7618 R08: ffffc900195b7690 R09: 000000000000000b
R10: 0000000000000004 R11: 0000000000000000 R12: 0000000000000014
R13: dffffc0000000000 R14: ffffffff81310bf7 R15: ffffffff8e9a3374
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f27047ea2f8 CR3: 0000000076ddd000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000400
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4e/0x70 mm/kasan/common.c:53
 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522
 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:237
 kasan_slab_free include/linux/kasan.h:164 [inline]
 slab_free_hook mm/slub.c:1811 [inline]
 slab_free_freelist_hook+0x130/0x1a0 mm/slub.c:1837
 slab_free mm/slub.c:3830 [inline]
 __kmem_cache_free+0xba/0x1e0 mm/slub.c:3843
 skb_kfree_head net/core/skbuff.c:946 [inline]
 skb_free_head net/core/skbuff.c:958 [inline]
 skb_release_data+0x5dc/0x7b0 net/core/skbuff.c:988
 skb_release_all net/core/skbuff.c:1054 [inline]
 __kfree_skb net/core/skbuff.c:1068 [inline]
 consume_skb+0xb2/0x110 net/core/skbuff.c:1284
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:821 [inline]
 nsim_dev_trap_report_work+0x76f/0xb00 drivers/net/netdevsim/dev.c:851
 process_one_work kernel/workqueue.c:2653 [inline]
 process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2730
 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2811
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/04/30 03:51 linux-6.6.y 142cd8382222 005438fc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan INFO: task hung in blkdev_flush_mapping
2026/04/19 18:26 linux-6.6.y 9760bf04666d 303e2802 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan INFO: task hung in blkdev_flush_mapping
2026/03/18 19:16 linux-6.6.y 4fc00fe35d46 0199f9a1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan INFO: task hung in blkdev_flush_mapping
* Struck through repros no longer work on HEAD.