INFO: rcu detected stall in unwind_get_return_address (2)

Status: upstream: reported C repro on 2026/08/24 17:54
Reported-by: syzbot+b2978e40c9b7c9959b25@syzkaller.appspotmail.com
First crash: 2d15h, last: 2d15h
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2026/08/26 upstream (ToT) [unknown] C Failed due to an error; will retry later
▶ ▼ Similar bugs (6)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in unwind_get_return_address bpf 1 1 695d 695d 0/29 auto-obsoleted due to no activity on 2024/12/29 10:05
linux-5.15 INFO: rcu detected stall in unwind_get_return_address 1 1 245d 245d 0/3 auto-obsoleted due to no activity on 2026/04/03 20:45
linux-6.1 INFO: rcu detected stall in unwind_get_return_address 1 1 188d 188d 0/3 auto-obsoleted due to no activity on 2026/05/31 04:58
linux-5.15 INFO: rcu detected stall in unwind_get_return_address (2) 1 1 24d 24d 0/3 upstream: reported on 2026/08/03 06:35
upstream INFO: rcu detected stall in unwind_get_return_address (2) bpf 1 syz error error 1 257d 253d 0/29 auto-obsoleted due to no activity on 2026/03/22 18:27
upstream INFO: rcu detected stall in unwind_get_return_address (3) prio:low bpf 1 1 94d 94d 0/29 auto-obsoleted due to no activity on 2026/08/22 11:04

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=cf9c/1/0x4000000000000002 softirq=10481/10482 fqs=15
	(detected by 0, t=10502 jiffies, g=10933, q=724 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4477 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:__this_cpu_preempt_check+0x0/0x10 lib/smp_processor_id.c:65
Code: 48 89 da e8 52 b8 f4 ff 48 8b 74 24 30 48 c7 c7 a0 61 df 8a e8 41 b8 f4 ff e8 0a 8c ff ff eb a8 e8 35 ea ff ff 0f 1f 44 00 00 <48> 89 fe 48 c7 c7 20 61 df 8a e9 e1 fe ff ff 00 eb 1e 0f 1f 00 48
RSP: 0018:ffffc900001e08a0 EFLAGS: 00000006
RAX: 0000000000010100 RBX: ffffc900001e08d8 RCX: ffffffff96c19103
RDX: 0000000000000000 RSI: ffffffff8a8660e0 RDI: ffffffff8a8b0e20
RBP: 0000000000000000 R08: ffffffff8e2110ef R09: 1ffffffff1c4221d
R10: dffffc0000000000 R11: fffffbfff1c4221e R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000000
FS:  0000555584b49500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000140 CR3: 000000006948c000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 irq_enter_rcu+0x23/0xe0 kernel/softirq.c:638
 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline]
 sysvec_irq_work+0x45/0xc0 arch/x86/kernel/irq_work.c:17
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:728
RIP: 0010:rcu_read_unlock_special+0x7f/0x510 kernel/rcu/tree_plugin.h:685
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 12 7c 95 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 40 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08
RSP: 0018:ffffc900001e0980 EFLAGS: 00000206
RAX: b65f874abad07b00 RBX: 1ffff9200003c138 RCX: b65f874abad07b00
RDX: dffffc0000000000 RSI: ffffffff8a8c1820 RDI: ffffffff8adf6120
RBP: ffffc900001e0a80 R08: ffffffff90b12347 R09: 1ffffffff2162468
R10: dffffc0000000000 R11: fffffbfff2162469 R12: 0000000000000246
R13: dffffc0000000000 R14: ffff8880b8f3bb00 R15: 0000000000000002
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426
 rcu_read_unlock include/linux/rcupdate.h:823 [inline]
 hsr_announce+0x2ca/0x340 net/hsr/hsr_device.c:407
 call_timer_fn+0x1ac/0x670 kernel/time/timer.c:1701
 expire_timers kernel/time/timer.c:1752 [inline]
 __run_timers+0x56c/0x810 kernel/time/timer.c:2023
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:2036
 handle_softirqs+0x291/0x910 kernel/softirq.c:596
 __do_softirq kernel/softirq.c:630 [inline]
 invoke_softirq kernel/softirq.c:470 [inline]
 __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:679
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:691
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:core_kernel_text kernel/extable.c:71 [inline]
RIP: 0010:kernel_text_address+0x49/0xd0 kernel/extable.c:99
Code: 75 0c 48 89 fb e8 d7 6e aa ff 85 c0 74 07 89 e8 5b 41 5e 5d c3 48 c7 c0 80 e2 20 8e 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <0f> b6 04 08 84 c0 75 5a 83 3d f8 ce ca 0c 01 77 18 48 81 fb 00 70
RSP: 0018:ffffc900035078d8 EFLAGS: 00000a06
RAX: 1ffffffff1c41c50 RBX: 00007f122ed9e0d9 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 00007f122ed9e000 RDI: ffffffffff600000
RBP: 0000000000000001 R08: 0000000000000004 R09: 000000000000000b
R10: dffffc0000000000 R11: fffff520006a0f31 R12: ffff88805be23c00
R13: ffffc90003507d48 R14: dffffc0000000000 R15: 1ffff920006a0f2e
 __kernel_text_address+0x9/0x30 kernel/extable.c:79
 unwind_get_return_address+0x49/0x80 arch/x86/kernel/unwind_orc.c:323
 arch_stack_walk+0xf2/0x140 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0x126/0x1f0 mm/kasan/common.c:237
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1729 [inline]
 slab_free_freelist_hook+0x133/0x1b0 mm/slub.c:1755
 slab_free mm/slub.c:3687 [inline]
 kmem_cache_free+0xf7/0x2a0 mm/slub.c:3709
 file_free fs/file_table.c:56 [inline]
 __fput+0x5cb/0x8b0 fs/file_table.c:333
 task_work_run+0x1d0/0x260 kernel/task_work.c:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f122ed9e0d9
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:00007ffc2d8e0d18 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007ffc2d8e0e00 RCX: 00007f122ed9e0d9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 0000000000018ee6 R08: 0000000000000001 R09: 0000000000000000
R10: 0000001b2db20000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f122f025fac R14: 00007f122f025fa8 R15: 00007f122f025fa0
 </TASK>
rcu: rcu_preempt kthread starved for 10470 jiffies! g10933 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:27888 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5246 [inline]
 __schedule+0x107f/0x4030 kernel/sched/core.c:6563
 schedule+0xb9/0x180 kernel/sched/core.c:6639
 schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2168
 rcu_gp_fqs_loop+0x303/0x1350 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0x99/0x3b0 kernel/rcu/tree.c:1905
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 PID: 4481 Comm: syz.1.22 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:orc_ip arch/x86/kernel/unwind_orc.c:30 [inline]
RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:52 [inline]
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:178 [inline]
RIP: 0010:unwind_next_frame+0x1212/0x1fd0 arch/x86/kernel/unwind_orc.c:448
Code: c1 48 c1 f9 02 48 c1 e8 3f 48 01 c8 48 83 e0 fe 4c 8d 7c 45 00 4c 89 f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 0f b6 04 08 <84> c0 75 27 49 63 07 4c 01 f8 49 8d 4f 04 4c 39 f0 48 0f 46 e9 49
RSP: 0000:ffffc900000075a0 EFLAGS: 00000a07
RAX: 0000000000000000 RBX: ffffc90000007648 RCX: dffffc0000000000
RDX: ffffffff8f18f85e RSI: ffffffff8e8101ac RDI: 0000000000000001
RBP: ffffffff8e8101ac R08: 0000000000000012 R09: 0000000000000006
R10: dffffc0000000000 R11: fffff52000000ed5 R12: ffffffff8e8101ac
R13: ffffffff8e8101f0 R14: ffffffff882f0a01 R15: ffffffff8e8101cc
FS:  000055555da15500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7bad3dde9c CR3: 000000005c9eb000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0x126/0x1f0 mm/kasan/common.c:237
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1729 [inline]
 slab_free_freelist_hook+0x133/0x1b0 mm/slub.c:1755
 slab_free mm/slub.c:3687 [inline]
 __kmem_cache_free+0xb6/0x200 mm/slub.c:3700
 skb_free_head net/core/skbuff.c:762 [inline]
 skb_release_data+0x5e9/0x7e0 net/core/skbuff.c:791
 skb_release_all net/core/skbuff.c:856 [inline]
 __kfree_skb net/core/skbuff.c:870 [inline]
 consume_skb+0xa2/0x100 net/core/skbuff.c:1035
 mac80211_hwsim_beacon_tx+0x608/0xae0 drivers/net/wireless/mac80211_hwsim.c:2121
 __iterate_interfaces+0x225/0x4c0 net/mac80211/util.c:788
 ieee80211_iterate_active_interfaces_atomic+0xd7/0x170 net/mac80211/util.c:824
 mac80211_hwsim_beacon+0xb7/0x1b0 drivers/net/wireless/mac80211_hwsim.c:2147
 __run_hrtimer kernel/time/hrtimer.c:1751 [inline]
 __hrtimer_run_queues+0x522/0xc90 kernel/time/hrtimer.c:1815
 hrtimer_run_softirq+0x173/0x290 kernel/time/hrtimer.c:1832
 handle_softirqs+0x291/0x910 kernel/softirq.c:596
 __do_softirq kernel/softirq.c:630 [inline]
 invoke_softirq kernel/softirq.c:470 [inline]
 __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:679
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:691
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:preempt_schedule_irq+0xb6/0x160 kernel/sched/core.c:6875
Code: 00 00 43 c6 44 37 04 f8 74 0b 0f 0b 48 f7 03 08 00 00 00 74 7f bf 01 00 00 00 e8 45 22 1f f7 e8 60 ff 4e f7 fb bf 01 00 00 00 <e8> 25 ba ff ff 43 c6 44 37 08 00 48 c7 44 24 40 00 00 00 00 9c 8f
RSP: 0000:ffffc90003527da0 EFLAGS: 00000286
RAX: 2fbef933bd41cd00 RBX: 0000000000000000 RCX: 2fbef933bd41cd00
RDX: dffffc0000000000 RSI: ffffffff8a8c1820 RDI: 0000000000000001
RBP: ffffc90003527e50 R08: ffff8880b8e3580b R09: 1ffff110171c6b01
R10: dffffc0000000000 R11: ffffed10171c6b02 R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff920006a4fb4
 irqentry_exit+0x63/0x70 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:exit_to_user_mode_loop+0x40/0x110 kernel/entry/common.c:164
Code: fb eb 1d e8 f2 17 c2 08 65 48 8b 05 8a 7a 93 7e 4c 8b 30 41 f7 c6 0e 30 02 00 0f 84 c4 00 00 00 e8 05 a5 19 00 fb 41 f6 c6 08 <74> 05 e8 f9 9f ca 08 41 f7 c6 00 10 00 00 74 08 48 89 df e8 e8 e9
RSP: 0000:ffffc90003527f10 EFLAGS: 00000202
RAX: 2fbef933bd41cd00 RBX: ffffc90003527f58 RCX: 2fbef933bd41cd00
RDX: dffffc0000000000 RSI: ffffffff8a8c1820 RDI: ffffffff8adf6120
RBP: 0000000000000000 R08: ffff8880b8e3580b R09: 1ffff110171c6b01
R10: dffffc0000000000 R11: ffffed10171c6b02 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000008 R15: ffff88802584da00
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
 irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:316
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0033:0x7f62ee464054
Code: 48 8d b8 d8 fe ff ff e8 0a b1 0d 00 85 c0 0f 84 a2 01 00 00 64 f0 83 2c 25 a0 ff ff ff 01 e8 b3 92 0c 00 48 8b 4c 24 08 8b 00 <48> 83 b9 88 00 00 00 ff 89 81 90 00 00 00 75 04 85 c0 74 1c 48 63
RSP: 002b:00007ffd2d3873f0 EFLAGS: 00000207
RAX: 000000000000000e RBX: 00007f62ee825fa0 RCX: 00007f62ee825fa0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000480
RBP: 00007f62ee635024 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007f62ee825fac R14: 00007f62ee825fa0 R15: 00007f62ee825fa0
 </TASK>
NMI backtrace for cpu 1
CPU: 1 PID: 4477 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:hlock_class kernel/locking/lockdep.c:240 [inline]
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4729 [inline]
RIP: 0010:__lock_acquire+0x5ff/0x7c40 kernel/locking/lockdep.c:5013
Code: c3 81 e3 ff 1f 00 00 c1 e8 03 25 f8 03 00 00 48 8d b8 40 22 b1 90 be 08 00 00 00 e8 db 67 6f 00 48 0f a3 1d 43 1d 4d 0f 73 1a <48> 8d 04 5b c1 e0 06 48 8d 98 00 a1 49 90 49 b8 00 00 00 00 00 fc
RSP: 0018:ffffc900001dfe80 EFLAGS: 00000057
RAX: 0000000000000001 RBX: 000000000000002d RCX: ffffffff816404f5
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff90b12240
RBP: ffffc900001e00b0 R08: ffffffff90b12247 R09: 1ffffffff2162448
R10: dffffc0000000000 R11: fffffbfff2162449 R12: ffff88805be246d8
R13: ffff88805be23c00 R14: 0000000000000002 R15: ffff88805be24750
FS:  0000555584b49500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000140 CR3: 000000006948c000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5676
 rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 rcu_read_lock include/linux/rcupdate.h:791 [inline]
 __perf_event_output kernel/events/core.c:7728 [inline]
 perf_event_output_forward+0xdf/0x2f0 kernel/events/core.c:7750
 __perf_event_overflow+0x457/0x630 kernel/events/core.c:9496
 perf_swevent_overflow+0x19b/0x230 kernel/events/core.c:9579
 perf_swevent_event+0x458/0x570 kernel/events/core.c:-1
 perf_tp_event+0x36b/0xc10 kernel/events/core.c:10064
 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10032
 perf_trace_preemptirq_template+0x268/0x320 include/trace/events/preemptirq.h:14
 trace_irq_enable_rcuidle+0xd3/0x140 include/trace/events/preemptirq.h:40
 trace_hardirqs_on+0x24/0x40 kernel/trace/trace_preemptirq.c:44
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:728
RIP: 0010:rcu_read_unlock_special+0x7f/0x510 kernel/rcu/tree_plugin.h:685
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 12 7c 95 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 40 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08
RSP: 0018:ffffc900001e0980 EFLAGS: 00000206
RAX: b65f874abad07b00 RBX: 1ffff9200003c138 RCX: b65f874abad07b00
RDX: dffffc0000000000 RSI: ffffffff8a8c1820 RDI: ffffffff8adf6120
RBP: ffffc900001e0a80 R08: ffffffff90b12347 R09: 1ffffffff2162468
R10: dffffc0000000000 R11: fffffbfff2162469 R12: 0000000000000246
R13: dffffc0000000000 R14: ffff8880b8f3bb00 R15: 0000000000000002
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426
 rcu_read_unlock include/linux/rcupdate.h:823 [inline]
 hsr_announce+0x2ca/0x340 net/hsr/hsr_device.c:407
 call_timer_fn+0x1ac/0x670 kernel/time/timer.c:1701
 expire_timers kernel/time/timer.c:1752 [inline]
 __run_timers+0x56c/0x810 kernel/time/timer.c:2023
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:2036
 handle_softirqs+0x291/0x910 kernel/softirq.c:596
 __do_softirq kernel/softirq.c:630 [inline]
 invoke_softirq kernel/softirq.c:470 [inline]
 __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:679
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:691
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:core_kernel_text kernel/extable.c:71 [inline]
RIP: 0010:kernel_text_address+0x49/0xd0 kernel/extable.c:99
Code: 75 0c 48 89 fb e8 d7 6e aa ff 85 c0 74 07 89 e8 5b 41 5e 5d c3 48 c7 c0 80 e2 20 8e 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <0f> b6 04 08 84 c0 75 5a 83 3d f8 ce ca 0c 01 77 18 48 81 fb 00 70
RSP: 0018:ffffc900035078d8 EFLAGS: 00000a06
RAX: 1ffffffff1c41c50 RBX: 00007f122ed9e0d9 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 00007f122ed9e000 RDI: ffffffffff600000
RBP: 0000000000000001 R08: 0000000000000004 R09: 000000000000000b
R10: dffffc0000000000 R11: fffff520006a0f31 R12: ffff88805be23c00
R13: ffffc90003507d48 R14: dffffc0000000000 R15: 1ffff920006a0f2e
 __kernel_text_address+0x9/0x30 kernel/extable.c:79
 unwind_get_return_address+0x49/0x80 arch/x86/kernel/unwind_orc.c:323
 arch_stack_walk+0xf2/0x140 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0x126/0x1f0 mm/kasan/common.c:237
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1729 [inline]
 slab_free_freelist_hook+0x133/0x1b0 mm/slub.c:1755
 slab_free mm/slub.c:3687 [inline]
 kmem_cache_free+0xf7/0x2a0 mm/slub.c:3709
 file_free fs/file_table.c:56 [inline]
 __fput+0x5cb/0x8b0 fs/file_table.c:333
 task_work_run+0x1d0/0x260 kernel/task_work.c:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f122ed9e0d9
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:00007ffc2d8e0d18 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007ffc2d8e0e00 RCX: 00007f122ed9e0d9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 0000000000018ee6 R08: 0000000000000001 R09: 0000000000000000
R10: 0000001b2db20000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f122f025fac R14: 00007f122f025fa8 R15: 00007f122f025fa0
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/24 17:54 linux-6.1.y 05208478041c b55bd4c3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in unwind_get_return_address
* Struck through repros no longer work on HEAD.