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INFO: rcu detected stall in tc_new_tfilter

Status: upstream: reported on 2026/05/14 23:53
Reported-by: syzbot+c0e4997fce167948c267@syzkaller.appspotmail.com
First crash: 2d06h, last: 2d06h
▶ ▼ Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in tc_new_tfilter net 1 1 1610d 1610d 0/29 closed as invalid on 2022/02/08 10:10

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-....: (3 ticks this GP) idle=787/1/0x4000000000000002 softirq=30917/30917 fqs=2100 
	(detected by 1, t=10505 jiffies, g=45461, q=9884)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 10951 Comm: syz.3.1276 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:kasan_record_aux_stack+0xb/0x100 mm/kasan/generic.c:-1
Code: 89 f2 be f5 00 00 00 e9 93 2c 4c 02 0f 1f 00 48 89 f2 be f8 00 00 00 e9 83 2c 4c 02 0f 1f 00 41 56 53 48 89 fb e8 a5 eb ff ff <48> 85 c0 0f 84 a7 00 00 00 48 89 c7 48 8b 40 08 48 89 f9 a8 01 0f
RSP: 0018:ffffc90000007350 EFLAGS: 00000086
RAX: ffffea0002e40ec0 RBX: ffff8880b903b1f0 RCX: ffffea0002e40ec8
RDX: ffffea0000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffff8880b903b1fb R09: 1ffff1101720763f
R10: dffffc0000000000 R11: ffffed1017207640 R12: 0000000000000000
R13: dffffc0000000001 R14: 0000000000000000 R15: ffff8880b903b1f8
FS:  00007f9a9f68e6c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000000f000 CR3: 0000000046bb8000 CR4: 00000000003506f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 irq_work_queue_on+0xf1/0x220 kernel/irq_work.c:101
 rcu_read_unlock_special+0x37b/0x4a0 kernel/rcu/tree_plugin.h:667
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422
 rcu_read_unlock include/linux/rcupdate.h:772 [inline]
 __perf_event_output kernel/events/core.c:7813 [inline]
 perf_event_output_forward+0x255/0x2e0 kernel/events/core.c:7822
 __perf_event_overflow+0x364/0x530 kernel/events/core.c:9515
 perf_tp_event+0x383/0xbf0 kernel/events/core.c:10047
 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10021
 perf_trace_preemptirq_template+0x2aa/0x360 include/trace/events/preemptirq.h:14
 trace_irq_enable_rcuidle+0x108/0x180 include/trace/events/preemptirq.h:40
 trace_hardirqs_on+0x57/0x80 kernel/trace/trace_preemptirq.c:44
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713
RIP: 0010:rcu_read_unlock_special+0x7f/0x4a0 kernel/rcu/tree_plugin.h:674
Code: eb 03 48 b8 f1 f1 f1 f1 f8 f2 f2 f2 4a 89 04 2b 42 c7 44 2b 08 f8 f3 f3 f3 65 44 8b 35 32 e1 9c 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08
RSP: 0018:ffffc90000007b00 EFLAGS: 00000206
RAX: 86bcba71d33a4400 RBX: 1ffff92000000f64 RCX: 86bcba71d33a4400
RDX: dffffc0000000000 RSI: ffffffff8a2b2800 RDI: ffffffff8a79fe00
RBP: ffffc90000007bd8 R08: ffffffff901d50c7 R09: 1ffffffff203aa18
R10: dffffc0000000000 R11: fffffbfff203aa19 R12: ffffffff8c323000
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422
 rcu_read_unlock include/linux/rcupdate.h:772 [inline]
 ieee80211_iterate_active_interfaces_atomic+0x132/0x140 net/mac80211/util.c:831
 mac80211_hwsim_beacon+0x9b/0x180 drivers/net/wireless/mac80211_hwsim.c:1865
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x4f2/0xb70 kernel/time/hrtimer.c:1749
 hrtimer_run_softirq+0x176/0x240 kernel/time/hrtimer.c:1766
 handle_softirqs+0x339/0x830 kernel/softirq.c:576
 __do_softirq kernel/softirq.c:610 [inline]
 invoke_softirq kernel/softirq.c:450 [inline]
 __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:console_unlock+0xcad/0x1120 kernel/printk/printk.c:2749
Code: 75 11 e8 d6 dc 18 00 4d 85 ff 75 16 e8 cc dc 18 00 eb 15 e8 c5 dc 18 00 e8 e0 71 5c 08 4d 85 ff 74 ea e8 b6 dc 18 00 fb 31 ff <89> de e8 0c e0 18 00 85 db 0f 94 c0 22 44 24 17 3c 01 75 1f e8 9a
RSP: 0018:ffffc9000313ec40 EFLAGS: 00000246
RAX: ffffffff816057da RBX: 0000000000000000 RCX: 0000000000080000
RDX: ffffc9001b1c1000 RSI: 00000000000327e9 RDI: 0000000000000000
RBP: ffffc9000313eeb0 R08: ffffffff901d50c7 R09: 1ffffffff203aa18
R10: dffffc0000000000 R11: fffffbfff203aa19 R12: 1ffffffff198d729
R13: 0000000000000064 R14: 0000000000000000 R15: 0000000000000200
 vprintk_emit+0xc0/0x150 kernel/printk/printk.c:2274
 _printk+0xda/0x130 kernel/printk/printk.c:2299
 __nla_validate_parse+0x2127/0x2940 lib/nlattr.c:625
 __nla_parse+0x3c/0x50 lib/nlattr.c:710
 __nlmsg_parse include/net/netlink.h:744 [inline]
 nlmsg_parse_deprecated include/net/netlink.h:783 [inline]
 tc_new_tfilter+0x2ad/0x18e0 net/sched/cls_api.c:1972
 rtnetlink_rcv_msg+0x893/0xf30 net/core/rtnetlink.c:5678
 netlink_rcv_skb+0x1f5/0x440 net/netlink/af_netlink.c:2507
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x774/0x920 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x8ba/0xbe0 net/netlink/af_netlink.c:1918
 sock_sendmsg_nosec net/socket.c:706 [inline]
 __sock_sendmsg net/socket.c:718 [inline]
 ____sys_sendmsg+0x5b7/0x8f0 net/socket.c:2445
 ___sys_sendmsg+0x236/0x2e0 net/socket.c:2499
 __sys_sendmsg net/socket.c:2528 [inline]
 __do_sys_sendmsg net/socket.c:2537 [inline]
 __se_sys_sendmsg+0x1af/0x290 net/socket.c:2535
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f9aa1434e59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f9a9f68e028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f9aa16adfa0 RCX: 00007f9aa1434e59
RDX: 0000000000000000 RSI: 0000200000000100 RDI: 0000000000000003
RBP: 00007f9aa14cad6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9aa16ae038 R14: 00007f9aa16adfa0 R15: 00007ffef10ff818
 </TASK>
NMI backtrace for cpu 0
CPU: 0 PID: 10951 Comm: syz.3.1276 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:native_apic_msr_eoi_write+0xb/0x10 arch/x86/include/asm/apic.h:214
Code: 8b 06 bf f0 03 00 00 89 de 5b 41 5e 41 5f ff e0 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b9 0b 08 00 00 31 c0 31 d2 0f 30 <c3> 0f 1f 40 00 81 ff cf 00 00 00 7f 0c 83 ff 20 74 2a 83 ff 30 74
RSP: 0018:ffffc90000007a20 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffffffff8be339c8 RCX: 000000000000080b
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000000000b0
RBP: 0000000000000000 R08: ffffffff8f0ea008 R09: ffffffff8f0ea018
R10: ffffffff8f0ea010 R11: ffffffff8f0ea003 R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000000
FS:  00007f9a9f68e6c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000000f000 CR3: 0000000046bb8000 CR4: 00000000003506f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 apic_eoi arch/x86/include/asm/apic.h:400 [inline]
 ack_APIC_irq arch/x86/include/asm/apic.h:446 [inline]
 __sysvec_irq_work+0x51/0x240 arch/x86/kernel/irq_work.c:19
 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline]
 sysvec_irq_work+0x4a/0xc0 arch/x86/kernel/irq_work.c:17
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713
RIP: 0010:rcu_read_unlock_special+0x7f/0x4a0 kernel/rcu/tree_plugin.h:674
Code: eb 03 48 b8 f1 f1 f1 f1 f8 f2 f2 f2 4a 89 04 2b 42 c7 44 2b 08 f8 f3 f3 f3 65 44 8b 35 32 e1 9c 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08
RSP: 0018:ffffc90000007b00 EFLAGS: 00000206
RAX: 86bcba71d33a4400 RBX: 1ffff92000000f64 RCX: 86bcba71d33a4400
RDX: dffffc0000000000 RSI: ffffffff8a2b2800 RDI: ffffffff8a79fe00
RBP: ffffc90000007bd8 R08: ffffffff901d50c7 R09: 1ffffffff203aa18
R10: dffffc0000000000 R11: fffffbfff203aa19 R12: ffffffff8c323000
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422
 rcu_read_unlock include/linux/rcupdate.h:772 [inline]
 ieee80211_iterate_active_interfaces_atomic+0x132/0x140 net/mac80211/util.c:831
 mac80211_hwsim_beacon+0x9b/0x180 drivers/net/wireless/mac80211_hwsim.c:1865
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x4f2/0xb70 kernel/time/hrtimer.c:1749
 hrtimer_run_softirq+0x176/0x240 kernel/time/hrtimer.c:1766
 handle_softirqs+0x339/0x830 kernel/softirq.c:576
 __do_softirq kernel/softirq.c:610 [inline]
 invoke_softirq kernel/softirq.c:450 [inline]
 __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:console_unlock+0xcad/0x1120 kernel/printk/printk.c:2749
Code: 75 11 e8 d6 dc 18 00 4d 85 ff 75 16 e8 cc dc 18 00 eb 15 e8 c5 dc 18 00 e8 e0 71 5c 08 4d 85 ff 74 ea e8 b6 dc 18 00 fb 31 ff <89> de e8 0c e0 18 00 85 db 0f 94 c0 22 44 24 17 3c 01 75 1f e8 9a
RSP: 0018:ffffc9000313ec40 EFLAGS: 00000246
RAX: ffffffff816057da RBX: 0000000000000000 RCX: 0000000000080000
RDX: ffffc9001b1c1000 RSI: 00000000000327e9 RDI: 0000000000000000
RBP: ffffc9000313eeb0 R08: ffffffff901d50c7 R09: 1ffffffff203aa18
R10: dffffc0000000000 R11: fffffbfff203aa19 R12: 1ffffffff198d729
R13: 0000000000000064 R14: 0000000000000000 R15: 0000000000000200
 vprintk_emit+0xc0/0x150 kernel/printk/printk.c:2274
 _printk+0xda/0x130 kernel/printk/printk.c:2299
 __nla_validate_parse+0x2127/0x2940 lib/nlattr.c:625
 __nla_parse+0x3c/0x50 lib/nlattr.c:710
 __nlmsg_parse include/net/netlink.h:744 [inline]
 nlmsg_parse_deprecated include/net/netlink.h:783 [inline]
 tc_new_tfilter+0x2ad/0x18e0 net/sched/cls_api.c:1972
 rtnetlink_rcv_msg+0x893/0xf30 net/core/rtnetlink.c:5678
 netlink_rcv_skb+0x1f5/0x440 net/netlink/af_netlink.c:2507
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x774/0x920 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x8ba/0xbe0 net/netlink/af_netlink.c:1918
 sock_sendmsg_nosec net/socket.c:706 [inline]
 __sock_sendmsg net/socket.c:718 [inline]
 ____sys_sendmsg+0x5b7/0x8f0 net/socket.c:2445
 ___sys_sendmsg+0x236/0x2e0 net/socket.c:2499
 __sys_sendmsg net/socket.c:2528 [inline]
 __do_sys_sendmsg net/socket.c:2537 [inline]
 __se_sys_sendmsg+0x1af/0x290 net/socket.c:2535
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f9aa1434e59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f9a9f68e028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f9aa16adfa0 RCX: 00007f9aa1434e59
RDX: 0000000000000000 RSI: 0000200000000100 RDI: 0000000000000003
RBP: 00007f9aa14cad6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9aa16ae038 R14: 00007f9aa16adfa0 R15: 00007ffef10ff818
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/05/14 23:53 linux-5.15.y de8dfb3f0278 6ccb967e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in tc_new_tfilter
* Struck through repros no longer work on HEAD.