INFO: task syz.1.18:6077 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.18 state:D stack:27832 pid:6077 tgid:6077 ppid:5945 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x10e9/0x6820 kernel/sched/core.c:7183 __schedule_loop kernel/sched/core.c:7262 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7277 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7334 rwsem_down_write_slowpath+0x4c2/0x12c0 kernel/locking/rwsem.c:1215 __down_write_common kernel/locking/rwsem.c:1347 [inline] __down_write kernel/locking/rwsem.c:1356 [inline] down_write+0x1c7/0x1f0 kernel/locking/rwsem.c:1626 inode_lock include/linux/fs.h:1029 [inline] blkdev_fallocate+0x24b/0x440 block/fops.c:907 vfs_fallocate+0x576/0x10d0 fs/open.c:338 ksys_fallocate fs/open.c:362 [inline] __do_sys_fallocate fs/open.c:367 [inline] __se_sys_fallocate fs/open.c:365 [inline] __x64_sys_fallocate+0xd5/0x140 fs/open.c:365 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd93839c819 RSP: 002b:00007ffd388a61c8 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 00007fd938615fa0 RCX: 00007fd93839c819 RDX: 0000000000000000 RSI: 0000000000000010 RDI: 0000000000000004 RBP: 00007fd938432c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000002000000400 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fd938615fac R14: 00007fd938615fa0 R15: 00007fd938615fa0 INFO: task syz.0.17:6078 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.17 state:D stack:27832 pid:6078 tgid:6078 ppid:5939 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x10e9/0x6820 kernel/sched/core.c:7183 __schedule_loop kernel/sched/core.c:7262 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7277 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7334 rwsem_down_write_slowpath+0x4c2/0x12c0 kernel/locking/rwsem.c:1215 __down_write_common kernel/locking/rwsem.c:1347 [inline] __down_write kernel/locking/rwsem.c:1356 [inline] down_write+0x1c7/0x1f0 kernel/locking/rwsem.c:1626 inode_lock include/linux/fs.h:1029 [inline] blkdev_fallocate+0x24b/0x440 block/fops.c:907 vfs_fallocate+0x576/0x10d0 fs/open.c:338 ksys_fallocate fs/open.c:362 [inline] __do_sys_fallocate fs/open.c:367 [inline] __se_sys_fallocate fs/open.c:365 [inline] __x64_sys_fallocate+0xd5/0x140 fs/open.c:365 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f754a19c819 RSP: 002b:00007ffd37cdbd58 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 00007f754a415fa0 RCX: 00007f754a19c819 RDX: 0000000000000000 RSI: 0000000000000010 RDI: 0000000000000004 RBP: 00007f754a232c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000002000000400 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f754a415fac R14: 00007f754a415fa0 R15: 00007f754a415fa0 INFO: task syz.2.19:6079 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.19 state:D stack:27832 pid:6079 tgid:6079 ppid:5942 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x10e9/0x6820 kernel/sched/core.c:7183 __schedule_loop kernel/sched/core.c:7262 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7277 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7334 rwsem_down_write_slowpath+0x4c2/0x12c0 kernel/locking/rwsem.c:1215 __down_write_common kernel/locking/rwsem.c:1347 [inline] __down_write kernel/locking/rwsem.c:1356 [inline] down_write+0x1c7/0x1f0 kernel/locking/rwsem.c:1626 inode_lock include/linux/fs.h:1029 [inline] blkdev_fallocate+0x24b/0x440 block/fops.c:907 vfs_fallocate+0x576/0x10d0 fs/open.c:338 ksys_fallocate fs/open.c:362 [inline] __do_sys_fallocate fs/open.c:367 [inline] __se_sys_fallocate fs/open.c:365 [inline] __x64_sys_fallocate+0xd5/0x140 fs/open.c:365 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fdb8279c819 RSP: 002b:00007ffce4cb8018 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 00007fdb82a15fa0 RCX: 00007fdb8279c819 RDX: 0000000000000000 RSI: 0000000000000010 RDI: 0000000000000004 RBP: 00007fdb82832c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000002000000400 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fdb82a15fac R14: 00007fdb82a15fa0 R15: 00007fdb82a15fa0 Showing all locks held in the system: 3 locks held by kworker/0:0/9: #0: ffff88813fe6b140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3263 #1: ffffc900000e7d08 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3264 #2: ffff888034e0f230 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x1b8/0x63b0 drivers/net/netdevsim/fib.c:1490 1 lock held by khungtaskd/31: #0: ffffffff8e7e7260 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffffffff8e7e7260 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:847 [inline] #0: ffffffff8e7e7260 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775 2 locks held by getty/5567: #0: ffff88803849b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900033332e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14f0 drivers/tty/n_tty.c:2211 2 locks held by syz.4.21/6076: 1 lock held by syz.1.18/6077: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.0.17/6078: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.2.19/6079: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.5.22/6176: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.9.26/6217: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.7.24/6218: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.6.23/6219: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.8.25/6220: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.3.27/6266: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.0.28/6309: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.4.31/6326: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.1.29/6327: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.2.30/6328: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.5.32/6355: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.9.33/6432: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.6.34/6450: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.8.36/6460: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.7.35/6461: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.3.37/6487: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.0.38/6549: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.4.39/6574: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.2.41/6576: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.1.40/6577: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.5.42/6603: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.9.43/6685: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.6.44/6712: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.7.45/6723: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.8.46/6728: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.3.47/6729: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.0.48/6765: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.4.49/6834: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.2.50/6837: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.1.51/6848: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.5.52/6849: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 1 lock held by syz.9.53/6879: #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff888027a61360 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_fallocate+0x24b/0x440 block/fops.c:907 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x1d7/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x141/0x190 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xd18/0x1040 kernel/hung_task.c:515 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 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: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63 Code: 36 82 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 33 8d 1a 00 fb f4 0c 43 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffffff8e407e00 EFLAGS: 00000242 RAX: 00000000001bfa25 RBX: ffffffff8e4955c0 RCX: ffffffff8b90ff35 RDX: 0000000000000000 RSI: ffffffff8de7f3ed RDI: ffffffff8c1b3de0 RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed10170867ad R10: ffff8880b8433d6b R11: 0000000000000000 R12: 0000000000000000 R13: fffffbfff1c92ab8 R14: 0000000000000000 R15: ffffffff90da4010 FS: 0000000000000000(0000) GS:ffff888124327000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b31163fff CR3: 00000000397ce000 CR4: 00000000003526f0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:62 [inline] default_idle+0x9/0x10 arch/x86/kernel/process.c:767 default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:199 [inline] do_idle+0x464/0x590 kernel/sched/idle.c:352 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:451 rest_init+0x251/0x260 init/main.c:762 start_kernel+0x484/0x490 init/main.c:1220 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x12b/0x130 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x148