INFO: task syz.4.28:6606 blocked for more than 143 seconds.
Not tainted syzkaller #0
Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.28 state:D stack:25768 pid:6606 tgid:6605 ppid:6295 task_flags:0x40054c flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1742/0x4c30 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
rwsem_down_write_slowpath+0x926/0x10e0 kernel/locking/rwsem.c:1185
__down_write_common kernel/locking/rwsem.c:1317 [inline]
__down_write kernel/locking/rwsem.c:1326 [inline]
down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1591
mmap_write_lock include/linux/mmap_lock.h:397 [inline]
exit_mmap+0x28b/0xb30 mm/mmap.c:1288
__mmput+0x118/0x420 kernel/fork.c:1129
exit_mm+0x1da/0x2c0 kernel/exit.c:582
do_exit+0x648/0x22f0 kernel/exit.c:949
do_group_exit+0x21c/0x2d0 kernel/exit.c:1102
get_signal+0x1252/0x1300 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:40
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x217/0x300 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7ff5f618eec9
RSP: 002b:00007ff5f6f7f0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007ff5f63e5fa8 RCX: 00007ff5f618eec9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007ff5f63e5fa8
RBP: 00007ff5f63e5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff5f63e6038 R14: 00007ffcadef6df0 R15: 00007ffcadef6ed8
INFO: task syz.4.28:6606 is blocked on an rw-semaphore, but the owner is not found.
INFO: task sed:6704 blocked for more than 143 seconds.
Not tainted syzkaller #0
Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:sed state:D stack:24000 pid:6704 tgid:6704 ppid:6703 task_flags:0x40000c flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1742/0x4c30 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
rwsem_down_write_slowpath+0x926/0x10e0 kernel/locking/rwsem.c:1185
__down_write_common kernel/locking/rwsem.c:1317 [inline]
__down_write kernel/locking/rwsem.c:1326 [inline]
down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1591
mmap_write_lock include/linux/mmap_lock.h:397 [inline]
exit_mmap+0x28b/0xb30 mm/mmap.c:1288
__mmput+0x118/0x420 kernel/fork.c:1129
exit_mm+0x1da/0x2c0 kernel/exit.c:582
do_exit+0x648/0x22f0 kernel/exit.c:949
do_group_exit+0x21c/0x2d0 kernel/exit.c:1102
__do_sys_exit_group kernel/exit.c:1113 [inline]
__se_sys_exit_group kernel/exit.c:1111 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1111
x64_sys_call+0x21f7/0x2200 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x8a/0x300 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f7a0a0ca6c5
RSP: 002b:00007fff3520fba8 EFLAGS: 00000206 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f7a0a1cbfe8 RCX: 00007f7a0a0ca6c5
RDX: 00000000000000e7 RSI: ffffffffffffff88 RDI: 0000000000000000
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f7a0a1ca680 R15: 00007f7a0a1cc000
INFO: task sed:6704 is blocked on an rw-semaphore, but the owner is not found.
INFO: task syz.2.63:6706 blocked for more than 144 seconds.
Not tainted syzkaller #0
Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.63 state:D stack:25768 pid:6706 tgid:6705 ppid:6281 task_flags:0x40054c flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1742/0x4c30 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
rwsem_down_write_slowpath+0x926/0x10e0 kernel/locking/rwsem.c:1185
__down_write_common kernel/locking/rwsem.c:1317 [inline]
__down_write kernel/locking/rwsem.c:1326 [inline]
down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1591
mmap_write_lock include/linux/mmap_lock.h:397 [inline]
exit_mmap+0x28b/0xb30 mm/mmap.c:1288
__mmput+0x118/0x420 kernel/fork.c:1129
exit_mm+0x1da/0x2c0 kernel/exit.c:582
do_exit+0x648/0x22f0 kernel/exit.c:949
do_group_exit+0x21c/0x2d0 kernel/exit.c:1102
get_signal+0x1252/0x1300 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:40
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x217/0x300 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f125d78eec9
RSP: 002b:00007f125e5540e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000001 RBX: 00007f125d9e5fa8 RCX: 00007f125d78eec9
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f125d9e5fac
RBP: 00007f125d9e5fa0 R08: 7fffffffffffffff R09: 0000000000000000
R10: 0000000000000006 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f125d9e6038 R14: 00007fff918bcd20 R15: 00007fff918bce08
INFO: task syz.2.63:6706 is blocked on an rw-semaphore, but the owner is not found.
INFO: task syz.1.74:6726 blocked for more than 144 seconds.
Not tainted syzkaller #0
Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.74 state:D stack:26904 pid:6726 tgid:6726 ppid:6279 task_flags:0x40004c flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1742/0x4c30 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
rwsem_down_write_slowpath+0x926/0x10e0 kernel/locking/rwsem.c:1185
__down_write_common kernel/locking/rwsem.c:1317 [inline]
__down_write kernel/locking/rwsem.c:1326 [inline]
down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1591
mmap_write_lock include/linux/mmap_lock.h:397 [inline]
exit_mmap+0x28b/0xb30 mm/mmap.c:1288
__mmput+0x118/0x420 kernel/fork.c:1129
exit_mm+0x1da/0x2c0 kernel/exit.c:582
do_exit+0x648/0x22f0 kernel/exit.c:949
do_group_exit+0x21c/0x2d0 kernel/exit.c:1102
__do_sys_exit_group kernel/exit.c:1113 [inline]
__se_sys_exit_group kernel/exit.c:1111 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1111
x64_sys_call+0x21f7/0x2200 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x8a/0x300 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fc63638eec9
RSP: 002b:00007ffcbc5c34f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fc63638eec9
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffcbc5c355c R08: 00000005bc5c35ef R09: 00000000000927c0
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000017
R13: 00000000000927c0 R14: 0000000000020fba R15: 00007ffcbc5c35b0
INFO: task syz.1.74:6726 is blocked on an rw-semaphore, but the owner is not found.
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff8db372a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8db372a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8db372a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
1 lock held by klogd/5082:
2 locks held by udevd/5093:
#0: ffffffff8dbeb330 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1484 [inline]
#0: ffffffff8dbeb330 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x131/0x4b0 kernel/fork.c:1537
#1: ffff88807eaa6d60 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:415 [inline]
#1: ffff88807eaa6d60 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x12d/0x1c50 mm/mmap.c:1727
2 locks held by getty/5478:
#0: ffff88803222e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900036c32f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x5ce/0x1ab0 drivers/tty/n_tty.c:2222
1 lock held by syz-execprog/6128:
#0: ffff888060b92220 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:415 [inline]
#0: ffff888060b92220 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x211/0x4d0 mm/util.c:578
1 lock held by syz-executor/6129:
#0: ffff888060b92ce0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:415 [inline]
#0: ffff888060b92ce0 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x211/0x4d0 mm/util.c:578
1 lock held by syz-executor/6275:
#0: ffff8880318fa220 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:397 [inline]
#0: ffff8880318fa220 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x28b/0xb30 mm/mmap.c:1288
1 lock held by syz-executor/6281:
#0: ffff8880318fb7a0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:397 [inline]
#0: ffff8880318fb7a0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x28b/0xb30 mm/mmap.c:1288
1 lock held by syz.4.28/6606:
#0: ffff888020fdace0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:397 [inline]
#0: ffff888020fdace0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x28b/0xb30 mm/mmap.c:1288
1 lock held by sed/6704:
#0: ffff88805c854d20 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:397 [inline]
#0: ffff88805c854d20 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x28b/0xb30 mm/mmap.c:1288
1 lock held by syz.2.63/6706:
#0: ffff88803254cd20 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:397 [inline]
#0: ffff88803254cd20 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x28b/0xb30 mm/mmap.c:1288
1 lock held by syz.0.64/6710:
#0: ffff888023de9760 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:397 [inline]
#0: ffff888023de9760 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x28b/0xb30 mm/mmap.c:1288
1 lock held by syz.1.74/6726:
#0: ffff88807e6e2220 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:397 [inline]
#0: ffff88807e6e2220 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x28b/0xb30 mm/mmap.c:1288
1 lock held by syz-executor/7579:
#0: ffff88807e6837a0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:397 [inline]
#0: ffff88807e6837a0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x28b/0xb30 mm/mmap.c:1288
1 lock held by udevd/7580:
#0: ffff88807e684260 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:415 [inline]
#0: ffff88807e684260 (&mm->mmap_lock){++++}-{4:4}, at: __vm_munmap+0x15c/0x3d0 mm/vma.c:3152
2 locks held by syz-executor/7700:
#0: ffffffff8dbeb330 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1484 [inline]
#0: ffffffff8dbeb330 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x131/0x4b0 kernel/fork.c:1537
#1: ffff88807eaa62a0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:415 [inline]
#1: ffff88807eaa62a0 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x12d/0x1c50 mm/mmap.c:1727
1 lock held by udevd/7707:
#0: ffff888027192ce0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:415 [inline]
#0: ffff888027192ce0 (&mm->mmap_lock){++++}-{4:4}, at: __vm_munmap+0x15c/0x3d0 mm/vma.c:3152
1 lock held by syz.5.500/7713:
#0: ffff88807b8cc260 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:397 [inline]
#0: ffff88807b8cc260 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x28b/0xb30 mm/mmap.c:1288
2 locks held by syz-executor/7716:
#0: ffffffff8dbeb330 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1484 [inline]
#0: ffffffff8dbeb330 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x131/0x4b0 kernel/fork.c:1537
#1: ffff888027190ca0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:415 [inline]
#1: ffff888027190ca0 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x12d/0x1c50 mm/mmap.c:1727
1 lock held by syz.3.647/7972:
#0: ffff88805ecac260 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:397 [inline]
#0: ffff88805ecac260 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x28b/0xb30 mm/mmap.c:1288
1 lock held by syz.9.927/8665:
#0: ffff88807d26d7e0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:397 [inline]
#0: ffff88807d26d7e0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x28b/0xb30 mm/mmap.c:1288
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x2e0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
watchdog+0x15af/0x15f0 kernel/hung_task.c:491
kthread+0x711/0x890 kernel/kthread.c:463
ret_from_fork+0x435/0x7c0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 36 Comm: kworker/u8:2 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Workqueue: bat_events batadv_nc_worker
RIP: 0010:__preempt_count_add arch/x86/include/asm/preempt.h:80 [inline]
RIP: 0010:rcu_is_watching+0x9/0xb0 kernel/rcu/tree.c:750
Code: 0e 03 eb cc 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 57 41 56 53 <65> ff 05 80 92 6f 10 e8 6b 51 60 09 89 c3 83 f8 08 73 65 49 bf 00
RSP: 0018:ffffc90000acf880 EFLAGS: 00000057
RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff81c3ea38
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8f32ac70
RBP: ffffc90000acf958 R08: ffffffff8f32ac77 R09: 1ffffffff1e6558e
R10: dffffc0000000000 R11: fffffbfff1e6558f R12: ffffffff8ad41cf8
R13: dffffc0000000000 R14: dffffc0000000000 R15: 1ffff92000159f18
FS: 0000000000000000(0000) GS:ffff8881266f3000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fba2afe7dac CR3: 000000007ea86000 CR4: 00000000003526f0
Call Trace:
trace_irq_enable+0x37/0x110 include/trace/events/preemptirq.h:40
trace_hardirqs_on+0x18/0x40 kernel/trace/trace_preemptirq.c:73
__local_bh_enable_ip+0x12d/0x1c0 kernel/softirq.c:412
spin_unlock_bh include/linux/spinlock.h:396 [inline]
batadv_nc_purge_paths+0x318/0x3b0 net/batman-adv/network-coding.c:471
batadv_nc_worker+0x369/0x610 net/batman-adv/network-coding.c:722
process_one_work kernel/workqueue.c:3236 [inline]
process_scheduled_works+0xa55/0x16a0 kernel/workqueue.c:3319
worker_thread+0xa57/0xfc0 kernel/workqueue.c:3400
kthread+0x711/0x890 kernel/kthread.c:463
ret_from_fork+0x435/0x7c0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245