syzbot

INFO: task syz.4.1219:10085 blocked for more than 143 seconds.
      Not tainted 6.14.0-rc5-syzkaller-00214-g21e4543a2e2f #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.1219      state:D stack:27360 pid:10085 tgid:10085 ppid:5817   task_flags:0x400040 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5378 [inline]
 __schedule+0xf43/0x5890 kernel/sched/core.c:6765
 __schedule_loop kernel/sched/core.c:6842 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6857
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6914
 rwsem_down_read_slowpath+0x61e/0xb20 kernel/locking/rwsem.c:1084
 __down_read_common kernel/locking/rwsem.c:1248 [inline]
 __down_read kernel/locking/rwsem.c:1261 [inline]
 down_read+0x124/0x330 kernel/locking/rwsem.c:1526
 filemap_invalidate_lock_shared include/linux/fs.h:932 [inline]
 filemap_fault+0x1845/0x2ca0 mm/filemap.c:3453
 __do_fault+0x10a/0x490 mm/memory.c:4988
 do_shared_fault mm/memory.c:5467 [inline]
 do_fault mm/memory.c:5541 [inline]
 do_pte_missing+0x1a8/0x3e10 mm/memory.c:4058
 handle_pte_fault mm/memory.c:5900 [inline]
 __handle_mm_fault+0x1166/0x2c60 mm/memory.c:6043
 handle_mm_fault+0x3fa/0xaa0 mm/memory.c:6212
 do_user_addr_fault+0x60d/0x13f0 arch/x86/mm/fault.c:1337
 handle_page_fault arch/x86/mm/fault.c:1480 [inline]
 exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1538
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x7f87dd853be3
RSP: 002b:00007ffe4824f740 EFLAGS: 00010246
RAX: 0000400000008980 RBX: 0000000000000008 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000555565ee23c8
RBP: 00007ffe4824f848 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 00007f87ddba5fac
R13: 00007f87ddba5fa0 R14: fffffffffffffffe R15: 00007ffe4824f890
 </TASK>
INFO: task syz.1.1220:10087 blocked for more than 144 seconds.
      Not tainted 6.14.0-rc5-syzkaller-00214-g21e4543a2e2f #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.1220      state:D stack:27936 pid:10087 tgid:10087 ppid:5816   task_flags:0x400040 flags:0x00000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5378 [inline]
 __schedule+0xf43/0x5890 kernel/sched/core.c:6765
 __schedule_loop kernel/sched/core.c:6842 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6857
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6914
 rwsem_down_read_slowpath+0x61e/0xb20 kernel/locking/rwsem.c:1084
 __down_read_common kernel/locking/rwsem.c:1248 [inline]
 __down_read kernel/locking/rwsem.c:1261 [inline]
 down_read+0x124/0x330 kernel/locking/rwsem.c:1526
 filemap_invalidate_lock_shared include/linux/fs.h:932 [inline]
 filemap_fault+0x1845/0x2ca0 mm/filemap.c:3453
 __do_fault+0x10a/0x490 mm/memory.c:4988
 do_shared_fault mm/memory.c:5467 [inline]
 do_fault mm/memory.c:5541 [inline]
 do_pte_missing+0x1a8/0x3e10 mm/memory.c:4058
 handle_pte_fault mm/memory.c:5900 [inline]
 __handle_mm_fault+0x1166/0x2c60 mm/memory.c:6043
 handle_mm_fault+0x3fa/0xaa0 mm/memory.c:6212
 do_user_addr_fault+0x60d/0x13f0 arch/x86/mm/fault.c:1337
 handle_page_fault arch/x86/mm/fault.c:1480 [inline]
 exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1538
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x7f4df5253be3
RSP: 002b:00007fffff140ca0 EFLAGS: 00010246
RAX: 0000400000008980 RBX: 0000000000000008 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000555585c173c8
RBP: 00007fffff140da8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 00007f4df55a5fac
R13: 00007f4df55a5fa0 R14: fffffffffffffffe R15: 00007fffff140df0
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/31:
 #0: ffffffff8e1bd0c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #0: ffffffff8e1bd0c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffffffff8e1bd0c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6746
2 locks held by getty/5579:
 #0: ffff88814d21f0a0 (&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
3 locks held by kworker/1:4/5868:
 #0: ffff88801b078d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3213
 #1: ffffc90003757d18 (key_gc_work){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3214
 #2: ffffffff8e1c8538 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x282/0x3b0 kernel/rcu/tree_exp.h:302
2 locks held by syz.3.1193/10006:
2 locks held by syz.4.1219/10085:
 #0: ffff888028d45658 (&vma->vm_lock->lock){++++}-{4:4}, at: vma_start_read include/linux/mm.h:717 [inline]
 #0: ffff888028d45658 (&vma->vm_lock->lock){++++}-{4:4}, at: lock_vma_under_rcu+0x13e/0x980 mm/memory.c:6378
 #1: ffff8880239059c0 (mapping.invalidate_lock#2){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:932 [inline]
 #1: ffff8880239059c0 (mapping.invalidate_lock#2){++++}-{4:4}, at: filemap_fault+0x1845/0x2ca0 mm/filemap.c:3453
2 locks held by syz.1.1220/10087:
 #0: ffff8880358d99b8 (&vma->vm_lock->lock){++++}-{4:4}, at: vma_start_read include/linux/mm.h:717 [inline]
 #0: ffff8880358d99b8 (&vma->vm_lock->lock){++++}-{4:4}, at: lock_vma_under_rcu+0x13e/0x980 mm/memory.c:6378
 #1: ffff8880239059c0 (mapping.invalidate_lock#2){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:932 [inline]
 #1: ffff8880239059c0 (mapping.invalidate_lock#2){++++}-{4:4}, at: filemap_fault+0x1845/0x2ca0 mm/filemap.c:3453
3 locks held by syz.6.1665/11693:
 #0: ffff88805c3b9a08 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:877 [inline]
 #0: ffff88805c3b9a08 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: __sock_release+0x86/0x270 net/socket.c:646
 #1: ffff88802acd9a58 (sk_lock-AF_QIPCRTR){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1624 [inline]
 #1: ffff88802acd9a58 (sk_lock-AF_QIPCRTR){+.+.}-{0:0}, at: qrtr_release+0x51/0x340 net/qrtr/af_qrtr.c:1213
 #2: ffffffff8e1c8538 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a4/0x3b0 kernel/rcu/tree_exp.h:334
1 lock held by syz.6.1665/11698:
 #0: ffffffff8fef7de8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:698 [inline]
 #0: ffffffff8fef7de8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x230 drivers/net/tun.c:3517

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.14.0-rc5-syzkaller-00214-g21e4543a2e2f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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:236 [inline]
 watchdog+0xf62/0x12b0 kernel/hung_task.c:399
 kthread+0x3af/0x750 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148
 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 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:111