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INFO: rcu detected stall in wait4 (5)

Status: auto-obsoleted due to no activity on 2025/01/30 05:34
Subsystems: fs
[Documentation on labels]
First crash: 161d, last: 130d
Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in wait4 (3) kernel 2 757d 762d 0/28 auto-obsoleted due to no activity on 2023/05/14 12:43
upstream INFO: rcu detected stall in wait4 kernel 2 1374d 1430d 0/28 auto-closed as invalid on 2021/09/04 10:15
upstream INFO: rcu detected stall in wait4 (4) kernel C error done 35 274d 602d 0/28 auto-obsoleted due to no activity on 2024/09/18 16:22
upstream INFO: rcu detected stall in wait4 (2) kernel 2 959d 1041d 0/28 auto-obsoleted due to no activity on 2022/10/24 16:24

Sample crash report:
rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-...D
 } 2636 jiffies s: 36425 root: 0x1/.
rcu: blocking rcu_node structures (internal RCU debug):

Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 2965 Comm: syz-executor Not tainted 6.12.0-rc4-syzkaller-00059-gc67e9601e29a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:io_serial_in+0x87/0xb0 drivers/tty/serial/8250/8250_port.c:407
Code: 68 b5 fe 48 8d 7d 40 44 89 e1 48 b8 00 00 00 00 00 fc ff df 48 89 fa d3 e3 48 c1 ea 03 80 3c 02 00 75 1a 66 03 5d 40 89 da ec <5b> 0f b6 c0 5d 41 5c c3 cc cc cc cc e8 78 ef 0d ff eb a2 e8 01 f0
RSP: 0018:ffffc90000006f00 EFLAGS: 00000002
RAX: dffffc0000000000 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: ffffffff82a08a30 RDI: ffffffff93637660
RBP: ffffffff93637620 R08: 0000000000000001 R09: 000000000000001f
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000020 R14: fffffbfff26c6f1e R15: dffffc0000000000
FS:  00005555843fd500(0000) GS:ffff8881f5800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c383a7e CR3: 0000000128cb0000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 serial_in drivers/tty/serial/8250/8250.h:137 [inline]
 serial_lsr_in drivers/tty/serial/8250/8250.h:159 [inline]
 wait_for_lsr+0xda/0x180 drivers/tty/serial/8250/8250_port.c:2068
 serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3315 [inline]
 serial8250_console_write+0xf5a/0x17c0 drivers/tty/serial/8250/8250_port.c:3393
 console_emit_next_record kernel/printk/printk.c:3092 [inline]
 console_flush_all+0x800/0xc60 kernel/printk/printk.c:3180
 __console_flush_and_unlock kernel/printk/printk.c:3239 [inline]
 console_unlock+0xd9/0x210 kernel/printk/printk.c:3279
 vprintk_emit+0x424/0x6f0 kernel/printk/printk.c:2407
 vprintk+0x7f/0xa0 kernel/printk/printk_safe.c:68
 _printk+0xc8/0x100 kernel/printk/printk.c:2432
 printk_stack_address arch/x86/kernel/dumpstack.c:72 [inline]
 show_trace_log_lvl+0x1b7/0x3d0 arch/x86/kernel/dumpstack.c:285
 sched_show_task kernel/sched/core.c:7604 [inline]
 sched_show_task+0x3f0/0x5f0 kernel/sched/core.c:7579
 show_state_filter+0xee/0x320 kernel/sched/core.c:7649
 k_spec drivers/tty/vt/keyboard.c:667 [inline]
 k_spec+0xed/0x150 drivers/tty/vt/keyboard.c:656
 kbd_keycode drivers/tty/vt/keyboard.c:1522 [inline]
 kbd_event+0xcbd/0x17a0 drivers/tty/vt/keyboard.c:1541
 input_handler_events_default+0x116/0x1b0 drivers/input/input.c:2549
 input_pass_values+0x777/0x8e0 drivers/input/input.c:126
 input_event_dispose drivers/input/input.c:352 [inline]
 input_handle_event+0xb30/0x14d0 drivers/input/input.c:369
 input_event drivers/input/input.c:398 [inline]
 input_event+0x83/0xa0 drivers/input/input.c:390
 hidinput_hid_event+0xa12/0x2410 drivers/hid/hid-input.c:1719
 hid_process_event+0x4b7/0x5e0 drivers/hid/hid-core.c:1540
 hid_input_array_field+0x330/0x710 drivers/hid/hid-core.c:1644
 hid_process_report drivers/hid/hid-core.c:1694 [inline]
 hid_report_raw_event+0xa02/0x11c0 drivers/hid/hid-core.c:2040
 __hid_input_report.constprop.0+0x341/0x440 drivers/hid/hid-core.c:2110
 hid_irq_in+0x35e/0x870 drivers/hid/usbhid/hid-core.c:285
 __usb_hcd_giveback_urb+0x389/0x6e0 drivers/usb/core/hcd.c:1650
 usb_hcd_giveback_urb+0x396/0x450 drivers/usb/core/hcd.c:1734
 dummy_timer+0x17f0/0x3930 drivers/usb/gadget/udc/dummy_hcd.c:1993
 __run_hrtimer kernel/time/hrtimer.c:1691 [inline]
 __hrtimer_run_queues+0x20a/0xae0 kernel/time/hrtimer.c:1755
 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1772
 handle_softirqs+0x206/0x8d0 kernel/softirq.c:554
 __do_softirq kernel/softirq.c:588 [inline]
 invoke_softirq kernel/softirq.c:428 [inline]
 __irq_exit_rcu kernel/softirq.c:637 [inline]
 irq_exit_rcu+0xac/0x110 kernel/softirq.c:649
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1049
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:cpu_max_bits_warn include/linux/cpumask.h:135 [inline]
RIP: 0010:cpumask_check include/linux/cpumask.h:142 [inline]
RIP: 0010:cpumask_test_cpu include/linux/cpumask.h:570 [inline]
RIP: 0010:cpu_online include/linux/cpumask.h:1117 [inline]
RIP: 0010:trace_sched_process_wait include/trace/events/sched.h:347 [inline]
RIP: 0010:do_wait+0x54/0x570 kernel/exit.c:1684
Code: 03 80 3c 02 00 0f 85 ec 04 00 00 4c 8b 6d 08 0f 1f 44 00 00 e8 3d 9c 39 00 49 c7 c4 0c c4 03 00 e8 31 9c 39 00 65 41 8b 1c 24 <bf> 07 00 00 00 89 de e8 60 9e 39 00 83 fb 07 0f 87 57 04 00 00 e8
RSP: 0018:ffffc900005efc80 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff811c6a0e
RDX: ffff88810375ba80 RSI: ffffffff811c568f RDI: ffffc900005efcf0
RBP: ffffc900005efce8 R08: 0000000000000005 R09: 00000000ffffffff
R10: 00000000ffffffff R11: 0000000000000000 R12: 000000000003c40c
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000004
 kernel_wait4+0x16c/0x280 kernel/exit.c:1851
 __do_sys_wait4+0x15f/0x170 kernel/exit.c:1879
 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: 0033:0x7f3ab9b34953
Code: 00 00 0f 1f 44 00 00 31 c9 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 80 3d f1 8b 19 00 00 49 89 ca 74 14 b8 3d 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 5d c3 0f 1f 40 00 48 83 ec 28 89 54 24 14 48
RSP: 002b:00007ffef4eff818 EFLAGS: 00000202 ORIG_RAX: 000000000000003d
RAX: ffffffffffffffda RBX: 000000000000056c RCX: 00007f3ab9b34953
RDX: 0000000040000001 RSI: 00007ffef4eff84c RDI: 00000000ffffffff
RBP: 00007ffef4eff84c R08: 000000000003344a R09: 00007f3ab99ba080
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000032
R13: 000000000011739e R14: 0000000000116e11 R15: 00007ffef4eff8a0
 </TASK>
 </TASK>

Showing all locks held in the system:
2 locks held by getty/2920:
 #0: ffff888108aaf0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
 #1: ffffc900000432f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211
4 locks held by syz-executor/2965:
 #0: ffff888133836230 (&dev->event_lock){..-.}-{2:2}, at: input_event drivers/input/input.c:397 [inline]
 #0: ffff888133836230 (&dev->event_lock){..-.}-{2:2}, at: input_event+0x70/0xa0 drivers/input/input.c:390
 #1: ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #1: ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #1: ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: input_pass_values+0x8b/0x8e0 drivers/input/input.c:118
 #2: ffffffff89387a58
 (kbd_event_lock){..-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
 (kbd_event_lock){..-.}-{2:2}, at: kbd_event+0x8a/0x17a0 drivers/tty/vt/keyboard.c:1535
 #3: ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #3: ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #3: ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6720
1 lock held by syz.1.2454/14149:
 #0: ffffffff88ec6a38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x282/0x3b0 kernel/rcu/tree_exp.h:297
1 lock held by syz.3.2455/14151:
 #0: ffffffff88ec6a38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x1a4/0x3b0 kernel/rcu/tree_exp.h:329

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


Crashes (6):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/11/01 05:34 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing c67e9601e29a 96eb609f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb INFO: rcu detected stall in wait4
2024/10/23 03:00 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing c6d9e43954bf 15fa2979 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb INFO: rcu detected stall in wait4
2024/10/19 06:14 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 07b887f8236e cd6fc0a3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb INFO: rcu detected stall in wait4
2024/10/16 02:10 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 64f3b5a6bc49 bde2d81c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb INFO: rcu detected stall in wait4
2024/10/03 06:03 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 9852d85ec9d4 a4c7fd36 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb INFO: rcu detected stall in wait4
2024/10/01 10:34 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 9852d85ec9d4 bbd4e0a4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb INFO: rcu detected stall in wait4
* Struck through repros no longer work on HEAD.