syzbot

INFO: task udevd:5843 blocked for more than 143 seconds.
      Not tainted 6.13.0-rc2-syzkaller-00018-g7cb1b4663150 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd           state:D stack:23392 pid:5843  tgid:5843  ppid:5206   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5369 [inline]
 __schedule+0xe58/0x5ad0 kernel/sched/core.c:6756
 __schedule_loop kernel/sched/core.c:6833 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6848
 io_schedule+0xbf/0x130 kernel/sched/core.c:7681
 folio_wait_bit_common+0x3d8/0x9b0 mm/filemap.c:1308
 folio_put_wait_locked mm/filemap.c:1472 [inline]
 do_read_cache_folio+0x342/0x5c0 mm/filemap.c:3808
 read_mapping_folio include/linux/pagemap.h:1011 [inline]
 read_part_sector+0xd4/0x310 block/partitions/core.c:722
 adfspart_check_POWERTEC+0xa0/0x6b0 block/partitions/acorn.c:454
 check_partition block/partitions/core.c:141 [inline]
 blk_add_partitions block/partitions/core.c:589 [inline]
 bdev_disk_changed+0x6c6/0x14e0 block/partitions/core.c:693
 blkdev_get_whole+0x187/0x290 block/bdev.c:707
 bdev_open+0x2c7/0xe20 block/bdev.c:916
 blkdev_open+0x329/0x400 block/fops.c:627
 do_dentry_open+0xf59/0x1ea0 fs/open.c:945
 vfs_open+0x82/0x3f0 fs/open.c:1075
 do_open fs/namei.c:3828 [inline]
 path_openat+0x1e6a/0x2d60 fs/namei.c:3987
 do_filp_open+0x20c/0x470 fs/namei.c:4014
 do_sys_openat2+0x17a/0x1e0 fs/open.c:1402
 do_sys_open fs/open.c:1417 [inline]
 __do_sys_openat fs/open.c:1433 [inline]
 __se_sys_openat fs/open.c:1428 [inline]
 __x64_sys_openat+0x175/0x210 fs/open.c:1428
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6c037169a4
RSP: 002b:00007ffcd697c2d0 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 000055c15d951e80 RCX: 00007f6c037169a4
RDX: 00000000000a0800 RSI: 000055c15d943b60 RDI: 00000000ffffff9c
RBP: 000055c15d943b60 R08: 0000000000000001 R09: 00007f6c03cda000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000000a0800
R13: 000055c15d952320 R14: 0000000000000001 R15: 000055c15d931910
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/30:
 #0: ffffffff8ddba940 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #0: ffffffff8ddba940 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffffffff8ddba940 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6744
2 locks held by getty/5593:
 #0: ffff8880311a60a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
 #1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211
1 lock held by udevd/5843:
 #0: ffff8880256e14c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe20 block/bdev.c:904
1 lock held by syz.3.1600/13214:
3 locks held by syz.3.1617/13271:

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-rc2-syzkaller-00018-g7cb1b4663150 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:234 [inline]
 watchdog+0xf14/0x1240 kernel/hung_task.c:397
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 13271 Comm: syz.3.1617 Not tainted 6.13.0-rc2-syzkaller-00018-g7cb1b4663150 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:lock_is_held include/linux/lockdep.h:249 [inline]
RIP: 0010:__might_resched+0x4b9/0x5e0 kernel/sched/core.c:8720
Code: 0f 85 d0 fb ff ff 48 c7 c2 c0 45 4c 8b be 10 22 00 00 48 c7 c7 80 3a 4c 8b c6 05 48 89 9d 0e 01 e8 8c e2 0d 00 e9 ac fb ff ff <be> ff ff ff ff 48 c7 c7 80 a8 db 8d e8 36 0c b2 09 85 c0 0f 84 a0
RSP: 0018:ffffc9000faa6ec0 EFLAGS: 00000202
RAX: 0000000000000001 RBX: 1ffff92001f54dda RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff8b4cd480 RDI: ffffffff8bb156e0
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000003 R12: ffffffff8b58f340
R13: 00000000000000e8 R14: ffff888029f9b488 R15: ffff888029f9b5f0
FS:  00007f25c52316c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5ba1b17178 CR3: 000000006b0b0000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 shmem_inode_acct_blocks+0xbd/0x450 mm/shmem.c:232
 shmem_alloc_and_add_folio+0x689/0xc00 mm/shmem.c:1863
 shmem_get_folio_gfp+0x689/0x1530 mm/shmem.c:2355
 shmem_get_folio mm/shmem.c:2461 [inline]
 shmem_write_begin+0x161/0x300 mm/shmem.c:3117
 generic_perform_write+0x2ba/0x920 mm/filemap.c:4055
 shmem_file_write_iter+0x10e/0x140 mm/shmem.c:3293
 __kernel_write_iter+0x318/0xa80 fs/read_write.c:612
 dump_emit_page fs/coredump.c:884 [inline]
 dump_user_range+0x389/0x8c0 fs/coredump.c:945
 elf_core_dump+0x2787/0x3880 fs/binfmt_elf.c:2129
 do_coredump+0x2dd5/0x43e0 fs/coredump.c:758
 get_signal+0x23f3/0x2610 kernel/signal.c:3002
 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218
 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f25c437ff19
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f25c52310e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007f25c4545fa8 RCX: 00007f25c437ff19
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f25c4545fac
RBP: 00007f25c4545fa0 R08: 00007f25c5232000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f25c4545fac
R13: 0000000000000000 R14: 00007ffff730a080 R15: 00007ffff730a168
 </TASK>