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INFO: rcu detected stall in tc_modify_qdisc

Status: upstream: reported on 2024/08/13 15:46
Reported-by: syzbot+6818656ac1d4c60d28ed@syzkaller.appspotmail.com
First crash: 70d, last: 35d
▶ ▼ Similar bugs (7)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: rcu detected stall in tc_modify_qdisc 3 99d 138d 0/3 upstream: reported on 2024/06/06 08:34
upstream INFO: rcu detected stall in tc_modify_qdisc net C done 528 1d00h 1546d 0/28 upstream: reported C repro on 2020/07/29 05:53
android-6-1 BUG: soft lockup in tc_modify_qdisc C done done 53 329d 361d 0/2 auto-obsoleted due to no activity on 2024/02/06 04:01
android-5-15 BUG: soft lockup in tc_modify_qdisc origin:lts C done done 254 418d 473d 0/2 auto-obsoleted due to no activity on 2023/11/09 01:01
linux-5.15 BUG: soft lockup in tc_modify_qdisc origin:upstream C error 1 507d 507d 0/3 auto-obsoleted due to no activity on 2023/09/11 01:53
linux-6.1 BUG: soft lockup in tc_modify_qdisc origin:upstream C done 1 506d 506d 3/3 fixed on 2023/07/10 11:22
android-5-10 BUG: soft lockup in tc_modify_qdisc C done done 314 420d 474d 0/2 auto-obsoleted due to no activity on 2023/11/07 07:54

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=ee7/1/0x4000000000000000 softirq=20020/20021 fqs=200 
	(detected by 0, t=10502 jiffies, g=29885, q=1081)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 5996 Comm: syz.3.500 Not tainted 5.15.164-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:193
Code: 1f 84 00 00 00 00 00 0f 1f 00 53 48 89 fb e8 17 00 00 00 48 8b 3d 08 ed 68 0c 48 89 de 5b e9 c7 fc 48 00 cc cc cc cc cc cc cc <48> 8b 04 24 65 48 8b 0d 54 0e 82 7e 65 8b 15 55 0e 82 7e f7 c2 00
RSP: 0018:ffffc90000dd0cb8 EFLAGS: 00000002
RAX: 0000000000010203 RBX: 0000000000000001 RCX: ffff8880777e3b80
RDX: ffff8880777e3b80 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffff8880204112e8 R08: ffffffff888103c4 R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: ffff888020411000
R13: ffff888020411340 R14: dffffc0000000000 R15: ffff8880777e4658
FS:  00007fd7aeb6c6c0(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2e616ff8 CR3: 00000000611b0000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 advance_sched+0x81/0x940 net/sched/sch_taprio.c:717
 __run_hrtimer kernel/time/hrtimer.c:1686 [inline]
 __hrtimer_run_queues+0x598/0xcf0 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xd4/0x130 kernel/locking/spinlock.c:194
Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 f2 90 8d f7 f6 44 24 21 02 75 4e 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> 97 c6 1a f7 65 8b 05 58 cb c5 75 85 c0 74 3f 48 c7 04 24 0e 36
RSP: 0018:ffffc90002d26ce0 EFLAGS: 00000206
RAX: 45c44c5f3b748b00 RBX: 1ffff920005a4da0 RCX: ffffffff816319d8
RDX: dffffc0000000000 RSI: ffffffff8a8b2a00 RDI: 0000000000000001
RBP: ffffc90002d26d70 R08: dffffc0000000000 R09: fffffbfff1f8e031
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffff920005a4d9c R14: ffffc90002d26d00 R15: 0000000000000246
 spin_unlock_irqrestore include/linux/spinlock.h:418 [inline]
 taprio_change+0x4278/0x5010 net/sched/sch_taprio.c:1617
 qdisc_create+0x8ae/0x1390 net/sched/sch_api.c:1264
 tc_modify_qdisc+0xb16/0x1760
 rtnetlink_rcv_msg+0x993/0xee0 net/core/rtnetlink.c:5629
 netlink_rcv_skb+0x1cf/0x410 net/netlink/af_netlink.c:2504
 netlink_unicast_kernel net/netlink/af_netlink.c:1326 [inline]
 netlink_unicast+0x7b6/0x980 net/netlink/af_netlink.c:1352
 netlink_sendmsg+0xa30/0xd60 net/netlink/af_netlink.c:1920
 sock_sendmsg_nosec net/socket.c:704 [inline]
 __sock_sendmsg net/socket.c:716 [inline]
 ____sys_sendmsg+0x59e/0x8f0 net/socket.c:2431
 ___sys_sendmsg+0x252/0x2e0 net/socket.c:2485
 __sys_sendmsg net/socket.c:2514 [inline]
 __do_sys_sendmsg net/socket.c:2523 [inline]
 __se_sys_sendmsg+0x19a/0x260 net/socket.c:2521
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fd7b06ef9f9
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:00007fd7aeb6c038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fd7b088bf80 RCX: 00007fd7b06ef9f9
RDX: 0000000000000000 RSI: 00000000200007c0 RDI: 0000000000000007
RBP: 00007fd7b075d8ee R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fd7b088bf80 R15: 00007ffdc8a510b8
 </TASK>
rcu: rcu_preempt kthread starved for 5669 jiffies! g29885 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R  running task     stack:26816 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1f0 kernel/sched/core.c:6459
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 0
CPU: 0 PID: 3912 Comm: kworker/u4:11 Not tainted 5.15.164-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
Workqueue: writeback wb_workfn (flush-8:0)
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_check_gp_kthread_starvation+0x1d2/0x240 kernel/rcu/tree_stall.h:487
 print_other_cpu_stall+0x137a/0x14d0 kernel/rcu/tree_stall.h:592
 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
 rcu_pending kernel/rcu/tree.c:3932 [inline]
 rcu_sched_clock_irq+0xa38/0x1150 kernel/rcu/tree.c:2619
 update_process_times+0x196/0x200 kernel/time/timer.c:1818
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1686 [inline]
 __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:csd_lock_wait kernel/smp.c:440 [inline]
RIP: 0010:smp_call_function_many_cond+0xa93/0xd90 kernel/smp.c:969
Code: 04 03 84 c0 0f 85 84 00 00 00 45 8b 7d 00 44 89 fe 83 e6 01 31 ff e8 7c cf 0b 00 41 83 e7 01 75 07 e8 11 cc 0b 00 eb 41 f3 90 <48> b8 00 00 00 00 00 fc ff df 0f b6 04 03 84 c0 75 11 41 f7 45 00
RSP: 0018:ffffc90003256500 EFLAGS: 00000293
RAX: ffffffff81749574 RBX: 1ffff110173680b9 RCX: ffff88807dc0d940
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90003256640 R08: ffffffff81749544 R09: ffffed101734767b
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000001
R13: ffff8880b9b405c8 R14: ffff8880b9a3b3c0 R15: 0000000000000001
 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1135
 __flush_tlb_multi arch/x86/include/asm/paravirt.h:87 [inline]
 flush_tlb_multi arch/x86/mm/tlb.c:900 [inline]
 flush_tlb_mm_range+0x2a5/0x4a0 arch/x86/mm/tlb.c:986
 flush_tlb_page arch/x86/include/asm/tlbflush.h:239 [inline]
 ptep_clear_flush+0x112/0x150 mm/pgtable-generic.c:97
 page_mkclean_one+0x428/0x7b0 mm/rmap.c:938
 rmap_walk_file+0x3f8/0x600 mm/rmap.c:2378
 rmap_walk mm/rmap.c:2396 [inline]
 page_mkclean+0x330/0x490 mm/rmap.c:1006
 clear_page_dirty_for_io+0x3ce/0xa60 mm/page-writeback.c:2749
 mpage_submit_page+0x90/0x230 fs/ext4/inode.c:2081
 mpage_process_page_bufs+0x6c8/0x8b0 fs/ext4/inode.c:2215
 mpage_prepare_extent_to_map+0xc9d/0x1150 fs/ext4/inode.c:2643
 ext4_writepages+0xcd0/0x3d10 fs/ext4/inode.c:2771
 do_writepages+0x481/0x730 mm/page-writeback.c:2386
 __writeback_single_inode+0x15b/0xe30 fs/fs-writeback.c:1647
 writeback_sb_inodes+0xbce/0x1a40 fs/fs-writeback.c:1930
 __writeback_inodes_wb+0x114/0x400 fs/fs-writeback.c:2001
 wb_writeback+0x465/0xc50 fs/fs-writeback.c:2106
 wb_check_old_data_flush fs/fs-writeback.c:2206 [inline]
 wb_do_writeback fs/fs-writeback.c:2259 [inline]
 wb_workfn+0xc55/0x1130 fs/fs-writeback.c:2288
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/08/13 15:46 linux-5.15.y 7e89efd3ae1c f21a18ca .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in tc_modify_qdisc
2024/09/17 19:58 linux-5.15.y 3a5928702e71 c673ca06 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 BUG: soft lockup in tc_modify_qdisc
* Struck through repros no longer work on HEAD.