FAULT_INJECTION: forcing a failure.
name fail_usercopy, interval 1, probability 0, space 0, times 0
======================================================
WARNING: possible circular locking dependency detected
6.15.0-rc4-syzkaller-00213-g3c44b2d615e6 #0 Not tainted
------------------------------------------------------
syz.0.2023/11148 is trying to acquire lock:
ffffffff8df2fa20 (console_owner){-...}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:336 [inline]
ffffffff8df2fa20 (console_owner){-...}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:346 [inline]
ffffffff8df2fa20 (console_owner){-...}-{0:0}, at: console_srcu_read_lock kernel/printk/printk.c:288 [inline]
ffffffff8df2fa20 (console_owner){-...}-{0:0}, at: console_flush_all+0x13a/0xc40 kernel/printk/printk.c:3203

but task is already holding lock:
ffff8880b88276d8 (hrtimer_bases.lock){-.-.}-{2:2}, at: lock_hrtimer_base kernel/time/hrtimer.c:171 [inline]
ffff8880b88276d8 (hrtimer_bases.lock){-.-.}-{2:2}, at: hrtimer_start_range_ns+0xd1/0x1080 kernel/time/hrtimer.c:1327

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (hrtimer_bases.lock){-.-.}-{2:2}:
       lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162
       lock_hrtimer_base kernel/time/hrtimer.c:171 [inline]
       hrtimer_start_range_ns+0xd1/0x1080 kernel/time/hrtimer.c:1327
       rpm_suspend+0x12d2/0x1720 drivers/base/power/runtime.c:617
       __pm_runtime_idle+0x12f/0x1a0 drivers/base/power/runtime.c:1112
       pm_runtime_put include/linux/pm_runtime.h:466 [inline]
       __device_attach+0x342/0x400 drivers/base/dd.c:1047
       bus_probe_device+0x185/0x260 drivers/base/bus.c:537
       device_add+0x7b6/0xb50 drivers/base/core.c:3692
       serdev_controller_add+0x85/0x5d0 drivers/tty/serdev/core.c:771
       serdev_tty_port_register+0x159/0x260 drivers/tty/serdev/serdev-ttyport.c:291
       tty_port_register_device_attr_serdev+0xe7/0x170 drivers/tty/tty_port.c:191
       serial_core_add_one_port drivers/tty/serial/serial_core.c:3182 [inline]
       serial_core_register_port+0x1063/0x2700 drivers/tty/serial/serial_core.c:3389
       serial8250_register_8250_port+0x16dc/0x2050 drivers/tty/serial/8250/8250_core.c:822
       serial_pnp_probe+0x527/0x790 drivers/tty/serial/8250/8250_pnp.c:480
       pnp_device_probe+0x308/0x4c0 drivers/pnp/driver.c:111
       call_driver_probe drivers/base/dd.c:-1 [inline]
       really_probe+0x26a/0x9a0 drivers/base/dd.c:657
       __driver_probe_device+0x18c/0x2f0 drivers/base/dd.c:799
       driver_probe_device+0x4f/0x430 drivers/base/dd.c:829
       __driver_attach+0x452/0x700 drivers/base/dd.c:1215
       bus_for_each_dev+0x230/0x2b0 drivers/base/bus.c:370
       bus_add_driver+0x345/0x640 drivers/base/bus.c:678
       driver_register+0x23a/0x320 drivers/base/driver.c:249
       serial8250_init+0xc2/0x1c0 drivers/tty/serial/8250/8250_platform.c:315
       do_one_initcall+0x233/0x820 init/main.c:1257
       do_initcall_level+0x137/0x1f0 init/main.c:1319
       do_initcalls+0x69/0xd0 init/main.c:1335
       kernel_init_freeable+0x3d9/0x570 init/main.c:1567
       kernel_init+0x1d/0x1d0 init/main.c:1457
       ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
       ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

-> #2 (&dev->power.lock){-.-.}-{3:3}:
       lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162
       __pm_runtime_resume+0x10f/0x180 drivers/base/power/runtime.c:1179
       pm_runtime_get include/linux/pm_runtime.h:414 [inline]
       __uart_start+0x171/0x440 drivers/tty/serial/serial_core.c:148
       uart_write+0x278/0xa40 drivers/tty/serial/serial_core.c:635
       process_output_block drivers/tty/n_tty.c:561 [inline]
       n_tty_write+0xd32/0x11d0 drivers/tty/n_tty.c:2377
       iterate_tty_write drivers/tty/tty_io.c:1015 [inline]
       file_tty_write+0x4fe/0x990 drivers/tty/tty_io.c:1090
       new_sync_write fs/read_write.c:591 [inline]
       vfs_write+0x548/0xa90 fs/read_write.c:684
       ksys_write+0x145/0x250 fs/read_write.c:736
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #1 (&port_lock_key){-...}-{3:3}:
       lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162
       uart_port_lock_irqsave include/linux/serial_core.h:715 [inline]
       serial8250_console_write+0x17e/0x1ba0 drivers/tty/serial/8250/8250_port.c:3415
       console_emit_next_record kernel/printk/printk.c:3138 [inline]
       console_flush_all+0x728/0xc40 kernel/printk/printk.c:3226
       __console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
       console_unlock+0xc4/0x270 kernel/printk/printk.c:3325
       vprintk_emit+0x5b7/0x7a0 kernel/printk/printk.c:2450
       _printk+0xcf/0x120 kernel/printk/printk.c:2475
       register_console+0xa8b/0xf90 kernel/printk/printk.c:4125
       univ8250_console_init+0x52/0x90 drivers/tty/serial/8250/8250_core.c:513
       console_init+0x1a1/0x670 kernel/printk/printk.c:4323
       start_kernel+0x2cb/0x4f0 init/main.c:1034
       x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:513
       x86_64_start_kernel+0x66/0x70 arch/x86/kernel/head64.c:494
       common_startup_64+0x13e/0x147

-> #0 (console_owner){-...}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3166 [inline]
       check_prevs_add kernel/locking/lockdep.c:3285 [inline]
       validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3909
       __lock_acquire+0xaac/0xd20 kernel/locking/lockdep.c:5235
       lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866
       console_lock_spinning_enable kernel/printk/printk.c:1924 [inline]
       console_emit_next_record kernel/printk/printk.c:3132 [inline]
       console_flush_all+0x6d2/0xc40 kernel/printk/printk.c:3226
       __console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
       console_unlock+0xc4/0x270 kernel/printk/printk.c:3325
       vprintk_emit+0x5b7/0x7a0 kernel/printk/printk.c:2450
       _printk+0xcf/0x120 kernel/printk/printk.c:2475
       fail_dump lib/fault-inject.c:66 [inline]
       should_fail_ex+0x3f5/0x560 lib/fault-inject.c:174
       strncpy_from_user+0x36/0x290 lib/strncpy_from_user.c:118
       strncpy_from_user_nofault+0x72/0x140 mm/maccess.c:193
       bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:215 [inline]
       ____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:310 [inline]
       bpf_probe_read_compat_str+0xe2/0x180 kernel/trace/bpf_trace.c:306
       bpf_prog_c1796171ffc7efef+0x3e/0x40
       bpf_dispatcher_nop_func include/linux/bpf.h:1316 [inline]
       __bpf_prog_run include/linux/filter.h:718 [inline]
       bpf_prog_run include/linux/filter.h:725 [inline]
       __bpf_trace_run kernel/trace/bpf_trace.c:2363 [inline]
       bpf_trace_run2+0x281/0x4b0 kernel/trace/bpf_trace.c:2404
       __bpf_trace_hrtimer_start+0xfa/0x150 include/trace/events/timer.h:222
       __do_trace_hrtimer_start include/trace/events/timer.h:222 [inline]
       trace_hrtimer_start include/trace/events/timer.h:222 [inline]
       debug_activate kernel/time/hrtimer.c:485 [inline]
       enqueue_hrtimer+0x33f/0x3a0 kernel/time/hrtimer.c:1088
       __hrtimer_start_range_ns kernel/time/hrtimer.c:1270 [inline]
       hrtimer_start_range_ns+0xd10/0x1080 kernel/time/hrtimer.c:1329
       schedule_hrtimeout_range_clock+0x123/0x2f0 kernel/time/sleep_timeout.c:213
       poll_schedule_timeout+0xd1/0x1b0 fs/select.c:241
       do_poll fs/select.c:958 [inline]
       do_sys_poll+0x744/0x1050 fs/select.c:1009
       __do_sys_ppoll fs/select.c:1115 [inline]
       __se_sys_ppoll+0x1ff/0x260 fs/select.c:1095
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

Chain exists of:
  console_owner --> &dev->power.lock --> hrtimer_bases.lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(hrtimer_bases.lock);
                               lock(&dev->power.lock);
                               lock(hrtimer_bases.lock);
  lock(console_owner);

 *** DEADLOCK ***

4 locks held by syz.0.2023/11148:
 #0: ffff8880b88276d8 (hrtimer_bases.lock){-.-.}-{2:2}, at: lock_hrtimer_base kernel/time/hrtimer.c:171 [inline]
 #0: ffff8880b88276d8 (hrtimer_bases.lock){-.-.}-{2:2}, at: hrtimer_start_range_ns+0xd1/0x1080 kernel/time/hrtimer.c:1327
 #1: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #1: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
 #1: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2362 [inline]
 #1: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: bpf_trace_run2+0x186/0x4b0 kernel/trace/bpf_trace.c:2404
 #2: ffffffff8df2fa80 (console_lock){+.+.}-{0:0}, at: _printk+0xcf/0x120 kernel/printk/printk.c:2475
 #3: ffffffff8de17350 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:336 [inline]
 #3: ffffffff8de17350 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:346 [inline]
 #3: ffffffff8de17350 (console_srcu){....}-{0:0}, at: console_srcu_read_lock kernel/printk/printk.c:288 [inline]
 #3: ffffffff8de17350 (console_srcu){....}-{0:0}, at: console_flush_all+0x13a/0xc40 kernel/printk/printk.c:3203

stack backtrace:
CPU: 0 UID: 0 PID: 11148 Comm: syz.0.2023 Not tainted 6.15.0-rc4-syzkaller-00213-g3c44b2d615e6 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_circular_bug+0x2ee/0x310 kernel/locking/lockdep.c:2079
 check_noncircular+0x134/0x160 kernel/locking/lockdep.c:2211
 check_prev_add kernel/locking/lockdep.c:3166 [inline]
 check_prevs_add kernel/locking/lockdep.c:3285 [inline]
 validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3909
 __lock_acquire+0xaac/0xd20 kernel/locking/lockdep.c:5235
 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866
 console_lock_spinning_enable kernel/printk/printk.c:1924 [inline]
 console_emit_next_record kernel/printk/printk.c:3132 [inline]
 console_flush_all+0x6d2/0xc40 kernel/printk/printk.c:3226
 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
 console_unlock+0xc4/0x270 kernel/printk/printk.c:3325
 vprintk_emit+0x5b7/0x7a0 kernel/printk/printk.c:2450
 _printk+0xcf/0x120 kernel/printk/printk.c:2475
 fail_dump lib/fault-inject.c:66 [inline]
 should_fail_ex+0x3f5/0x560 lib/fault-inject.c:174
 strncpy_from_user+0x36/0x290 lib/strncpy_from_user.c:118
 strncpy_from_user_nofault+0x72/0x140 mm/maccess.c:193
 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:215 [inline]
 ____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:310 [inline]
 bpf_probe_read_compat_str+0xe2/0x180 kernel/trace/bpf_trace.c:306
 bpf_prog_c1796171ffc7efef+0x3e/0x40
 bpf_dispatcher_nop_func include/linux/bpf.h:1316 [inline]
 __bpf_prog_run include/linux/filter.h:718 [inline]
 bpf_prog_run include/linux/filter.h:725 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2363 [inline]
 bpf_trace_run2+0x281/0x4b0 kernel/trace/bpf_trace.c:2404
 __bpf_trace_hrtimer_start+0xfa/0x150 include/trace/events/timer.h:222
 __do_trace_hrtimer_start include/trace/events/timer.h:222 [inline]
 trace_hrtimer_start include/trace/events/timer.h:222 [inline]
 debug_activate kernel/time/hrtimer.c:485 [inline]
 enqueue_hrtimer+0x33f/0x3a0 kernel/time/hrtimer.c:1088
 __hrtimer_start_range_ns kernel/time/hrtimer.c:1270 [inline]
 hrtimer_start_range_ns+0xd10/0x1080 kernel/time/hrtimer.c:1329
 schedule_hrtimeout_range_clock+0x123/0x2f0 kernel/time/sleep_timeout.c:213
 poll_schedule_timeout+0xd1/0x1b0 fs/select.c:241
 do_poll fs/select.c:958 [inline]
 do_sys_poll+0x744/0x1050 fs/select.c:1009
 __do_sys_ppoll fs/select.c:1115 [inline]
 __se_sys_ppoll+0x1ff/0x260 fs/select.c:1095
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd41e18e969
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:00007fd41f064038 EFLAGS: 00000246 ORIG_RAX: 000000000000010f
RAX: ffffffffffffffda RBX: 00007fd41e3b5fa0 RCX: 00007fd41e18e969
RDX: 0000200000000100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fd41f064090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 0000000000000000 R14: 00007fd41e3b5fa0 R15: 00007ffe0a43f938
 </TASK>
CPU: 0 UID: 0 PID: 11148 Comm: syz.0.2023 Not tainted 6.15.0-rc4-syzkaller-00213-g3c44b2d615e6 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 fail_dump lib/fault-inject.c:73 [inline]
 should_fail_ex+0x414/0x560 lib/fault-inject.c:174
 strncpy_from_user+0x36/0x290 lib/strncpy_from_user.c:118
 strncpy_from_user_nofault+0x72/0x140 mm/maccess.c:193
 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:215 [inline]
 ____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:310 [inline]
 bpf_probe_read_compat_str+0xe2/0x180 kernel/trace/bpf_trace.c:306
 bpf_prog_c1796171ffc7efef+0x3e/0x40
 bpf_dispatcher_nop_func include/linux/bpf.h:1316 [inline]
 __bpf_prog_run include/linux/filter.h:718 [inline]
 bpf_prog_run include/linux/filter.h:725 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2363 [inline]
 bpf_trace_run2+0x281/0x4b0 kernel/trace/bpf_trace.c:2404
 __bpf_trace_hrtimer_start+0xfa/0x150 include/trace/events/timer.h:222
 __do_trace_hrtimer_start include/trace/events/timer.h:222 [inline]
 trace_hrtimer_start include/trace/events/timer.h:222 [inline]
 debug_activate kernel/time/hrtimer.c:485 [inline]
 enqueue_hrtimer+0x33f/0x3a0 kernel/time/hrtimer.c:1088
 __hrtimer_start_range_ns kernel/time/hrtimer.c:1270 [inline]
 hrtimer_start_range_ns+0xd10/0x1080 kernel/time/hrtimer.c:1329
 schedule_hrtimeout_range_clock+0x123/0x2f0 kernel/time/sleep_timeout.c:213
 poll_schedule_timeout+0xd1/0x1b0 fs/select.c:241
 do_poll fs/select.c:958 [inline]
 do_sys_poll+0x744/0x1050 fs/select.c:1009
 __do_sys_ppoll fs/select.c:1115 [inline]
 __se_sys_ppoll+0x1ff/0x260 fs/select.c:1095
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd41e18e969
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:00007fd41f064038 EFLAGS: 00000246 ORIG_RAX: 000000000000010f
RAX: ffffffffffffffda RBX: 00007fd41e3b5fa0 RCX: 00007fd41e18e969
RDX: 0000200000000100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fd41f064090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 0000000000000000 R14: 00007fd41e3b5fa0 R15: 00007ffe0a43f938
 </TASK>