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INFO: rcu detected stall in tty_ioctl (3)

Status: auto-obsoleted due to no activity on 2023/11/10 16:15
Subsystems: serial
[Documentation on labels]
First crash: 264d, last: 264d
▶ ▼ Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in tty_ioctl serial C 12 2313d 2325d 4/26 fixed on 2018/02/14 17:52
upstream INFO: rcu detected stall in tty_ioctl (2) serial 5 903d 912d 0/26 closed as invalid on 2022/02/08 10:00

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (10500 ticks this GP) idle=6764/1/0x4000000000000000 softirq=11821/11821 fqs=0
rcu: 	(t=10501 jiffies g=8445 q=657 ncpus=2)
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g8445 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=14054
rcu: rcu_preempt kthread starved for 10504 jiffies! g8445 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:I stack:28672 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0xee1/0x59f0 kernel/sched/core.c:6710
 schedule+0xe7/0x1b0 kernel/sched/core.c:6786
 schedule_timeout+0x157/0x2c0 kernel/time/timer.c:2167
 rcu_gp_fqs_loop+0x1ec/0xa50 kernel/rcu/tree.c:1609
 rcu_gp_kthread+0x249/0x380 kernel/rcu/tree.c:1808
 kthread+0x33a/0x430 kernel/kthread.c:389
 ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 PID: 5855 Comm: syz-executor.4 Not tainted 6.5.0-rc5-syzkaller-00296-gf8de32cc060b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
RIP: 0010:check_kcov_mode kernel/kcov.c:173 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x11/0x70 kernel/kcov.c:207
Code: b0 01 00 00 e8 b0 ff ff ff 31 c0 c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 f3 0f 1e fa 65 8b 05 dd b0 7d 7e 89 c1 48 8b 34 24 <81> e1 00 01 00 00 65 48 8b 14 25 80 b9 03 00 a9 00 01 ff 00 74 0e
RSP: 0018:ffffc90000007d58 EFLAGS: 00000287
RAX: 0000000000000102 RBX: ffff88803c082394 RCX: 0000000000000102
RDX: ffff88803a935940 RSI: ffffffff88594cab RDI: 0000000000000004
RBP: 0000000000000009 R08: 0000000000000004 R09: 0000000000000009
R10: 0000000000000010 R11: ffffc90000007ff8 R12: 0000000000000010
R13: ffff88803b47eb60 R14: 000000000000000c R15: 0000000000000001
FS:  00007fcb52f476c0(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4d61ac56be CR3: 000000001f587000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 taprio_dequeue_tc_priority+0x38b/0x4b0 net/sched/sch_taprio.c:806
 taprio_dequeue+0x12e/0x5f0 net/sched/sch_taprio.c:868
 dequeue_skb net/sched/sch_generic.c:292 [inline]
 qdisc_restart net/sched/sch_generic.c:397 [inline]
 __qdisc_run+0x1c4/0x19d0 net/sched/sch_generic.c:415
 qdisc_run include/net/pkt_sched.h:125 [inline]
 qdisc_run include/net/pkt_sched.h:122 [inline]
 net_tx_action+0x71e/0xc80 net/core/dev.c:5049
 __do_softirq+0x218/0x965 kernel/softirq.c:553
 invoke_softirq kernel/softirq.c:427 [inline]
 __irq_exit_rcu kernel/softirq.c:632 [inline]
 irq_exit_rcu+0xb7/0x120 kernel/softirq.c:644
 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1109
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x70 kernel/locking/spinlock.c:194
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 f6 5d 31 f7 48 89 df e8 ce dc 31 f7 f7 c5 00 02 00 00 75 1f 9c 58 f6 c4 02 75 2f <bf> 01 00 00 00 e8 75 7f 23 f7 65 8b 05 46 0d ce 75 85 c0 74 12 5b
RSP: 0018:ffffc90014c0fb78 EFLAGS: 00000246
RAX: 0000000000000002 RBX: ffff888039e41450 RCX: 1ffffffff23119ac
RDX: 0000000000000000 RSI: ffffffff8a6c80a0 RDI: ffffffff8ac81040
RBP: 0000000000000283 R08: 0000000000000001 R09: fffffbfff2309de2
R10: ffffffff9184ef17 R11: 0000000000000000 R12: 0000000000000400
R13: 0000000000004500 R14: dffffc0000000000 R15: ffff888039e41000
 n_tty_receive_char_flow_ctrl drivers/tty/n_tty.c:1263 [inline]
 n_tty_receive_char_special drivers/tty/n_tty.c:1272 [inline]
 n_tty_receive_buf_standard+0xda6/0x3300 drivers/tty/n_tty.c:1586
 __receive_buf drivers/tty/n_tty.c:1612 [inline]
 n_tty_receive_buf_common+0x344/0x15e0 drivers/tty/n_tty.c:1710
 tiocsti drivers/tty/tty_io.c:2301 [inline]
 tty_ioctl+0x590/0x1580 drivers/tty/tty_io.c:2700
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl fs/ioctl.c:856 [inline]
 __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fcb5227cae9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fcb52f470c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fcb5239bf80 RCX: 00007fcb5227cae9
RDX: 00000000200000c0 RSI: 0000000000005412 RDI: 0000000000000004
RBP: 00007fcb522c847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fcb5239bf80 R15: 00007ffd82b4c008
 </TASK>
CPU: 0 PID: 5855 Comm: syz-executor.4 Not tainted 6.5.0-rc5-syzkaller-00296-gf8de32cc060b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
RIP: 0010:check_kcov_mode kernel/kcov.c:173 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x11/0x70 kernel/kcov.c:207
Code: b0 01 00 00 e8 b0 ff ff ff 31 c0 c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 f3 0f 1e fa 65 8b 05 dd b0 7d 7e 89 c1 48 8b 34 24 <81> e1 00 01 00 00 65 48 8b 14 25 80 b9 03 00 a9 00 01 ff 00 74 0e
RSP: 0018:ffffc90000007d58 EFLAGS: 00000287
RAX: 0000000000000102 RBX: ffff88803c082394 RCX: 0000000000000102
RDX: ffff88803a935940 RSI: ffffffff88594cab RDI: 0000000000000004
RBP: 0000000000000009 R08: 0000000000000004 R09: 0000000000000009
R10: 0000000000000010 R11: ffffc90000007ff8 R12: 0000000000000010
R13: ffff88803b47eb60 R14: 000000000000000c R15: 0000000000000001
FS:  00007fcb52f476c0(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4d61ac56be CR3: 000000001f587000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 taprio_dequeue_tc_priority+0x38b/0x4b0 net/sched/sch_taprio.c:806
 taprio_dequeue+0x12e/0x5f0 net/sched/sch_taprio.c:868
 dequeue_skb net/sched/sch_generic.c:292 [inline]
 qdisc_restart net/sched/sch_generic.c:397 [inline]
 __qdisc_run+0x1c4/0x19d0 net/sched/sch_generic.c:415
 qdisc_run include/net/pkt_sched.h:125 [inline]
 qdisc_run include/net/pkt_sched.h:122 [inline]
 net_tx_action+0x71e/0xc80 net/core/dev.c:5049
 __do_softirq+0x218/0x965 kernel/softirq.c:553
 invoke_softirq kernel/softirq.c:427 [inline]
 __irq_exit_rcu kernel/softirq.c:632 [inline]
 irq_exit_rcu+0xb7/0x120 kernel/softirq.c:644
 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1109
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x70 kernel/locking/spinlock.c:194
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 f6 5d 31 f7 48 89 df e8 ce dc 31 f7 f7 c5 00 02 00 00 75 1f 9c 58 f6 c4 02 75 2f <bf> 01 00 00 00 e8 75 7f 23 f7 65 8b 05 46 0d ce 75 85 c0 74 12 5b
RSP: 0018:ffffc90014c0fb78 EFLAGS: 00000246
RAX: 0000000000000002 RBX: ffff888039e41450 RCX: 1ffffffff23119ac
RDX: 0000000000000000 RSI: ffffffff8a6c80a0 RDI: ffffffff8ac81040
RBP: 0000000000000283 R08: 0000000000000001 R09: fffffbfff2309de2
R10: ffffffff9184ef17 R11: 0000000000000000 R12: 0000000000000400
R13: 0000000000004500 R14: dffffc0000000000 R15: ffff888039e41000
 n_tty_receive_char_flow_ctrl drivers/tty/n_tty.c:1263 [inline]
 n_tty_receive_char_special drivers/tty/n_tty.c:1272 [inline]
 n_tty_receive_buf_standard+0xda6/0x3300 drivers/tty/n_tty.c:1586
 __receive_buf drivers/tty/n_tty.c:1612 [inline]
 n_tty_receive_buf_common+0x344/0x15e0 drivers/tty/n_tty.c:1710
 tiocsti drivers/tty/tty_io.c:2301 [inline]
 tty_ioctl+0x590/0x1580 drivers/tty/tty_io.c:2700
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl fs/ioctl.c:856 [inline]
 __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fcb5227cae9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fcb52f470c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fcb5239bf80 RCX: 00007fcb5227cae9
RDX: 00000000200000c0 RSI: 0000000000005412 RDI: 0000000000000004
RBP: 00007fcb522c847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fcb5239bf80 R15: 00007ffd82b4c008
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/08/12 16:07 upstream f8de32cc060b 39990d51 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in tty_ioctl
* Struck through repros no longer work on HEAD.