INFO: rcu detected stall in sys_exit_group (3)

Status: upstream: reported C repro on 2024/01/23 11:05
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+6f38629d8f83a72bd6f7@syzkaller.appspotmail.com
First crash: 922d, last: 16d
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2024/02/23 upstream (ToT) ffd2cb6b718e C [report] INFO: rcu detected stall in syscall_exit_to_user_mode
▶ ▼ Similar bugs (17)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_exit_group (7) net 1 syz, C unreliable inconclusive 90 755d 1752d 0/29 upstream: reported C repro on 2021/10/15 18:41
upstream INFO: rcu detected stall in sys_exit_group (6) mm 1 syz, C 4 2132d 2138d 19/29 fixed on 2021/03/10 01:48
linux-5.15 INFO: rcu detected stall in sys_exit_group (2) 1 3 836d 871d 0/3 auto-obsoleted due to no activity on 2024/07/27 04:53
linux-6.1 INFO: rcu detected stall in sys_exit_group (2) 1 1 1069d 1069d 0/3 auto-obsoleted due to no activity on 2023/12/07 20:57
linux-6.1 INFO: rcu detected stall in sys_exit_group 1 1 1180d 1180d 0/3 auto-obsoleted due to no activity on 2023/08/23 09:06
linux-5.15 INFO: rcu detected stall in sys_exit_group 1 1 1131d 1131d 0/3 auto-obsoleted due to no activity on 2023/10/06 21:30
upstream INFO: rcu detected stall in sys_exit_group (2) mm cgroups 1 56 2433d 2435d 0/29 closed as invalid on 2019/12/04 14:14
linux-6.6 INFO: rcu detected stall in sys_exit_group origin:upstream 1 syz, C error 16 29d 377d 0/2 upstream: reported C repro on 2025/07/21 16:02
upstream INFO: rcu detected stall in sys_exit_group (3) mm 1 8 2398d 2398d 0/29 closed as invalid on 2020/01/08 05:23
upstream INFO: rcu detected stall in sys_exit_group (4) mm 1 13 2398d 2398d 0/29 closed as invalid on 2020/01/09 08:13
upstream INFO: rcu detected stall in sys_exit_group (5) mm 1 1 2319d 2319d 0/29 auto-closed as invalid on 2020/06/25 07:58
linux-5.15 INFO: rcu detected stall in sys_exit_group (3) 1 2 626d 659d 0/3 auto-obsoleted due to no activity on 2025/02/22 19:05
linux-5.15 INFO: rcu detected stall in sys_exit_group (4) origin:upstream 1 syz, C error 8 65d 317d 0/3 upstream: reported C repro on 2025/09/19 02:54
upstream INFO: rcu detected stall in sys_exit_group kernel 1 syz, C done 1 2514d 2510d 13/29 fixed on 2019/10/09 10:54
android-5-10 BUG: soft lockup in sys_exit_group 1 1 742d 742d 0/2 auto-obsoleted due to no activity on 2024/10/19 10:22
android-5-10 BUG: soft lockup in sys_exit_group (2) 1 1 185d 185d 0/2 auto-obsoleted due to no activity on 2026/04/29 20:43
android-5-15 BUG: soft lockup in sys_exit_group 1 syz, C error 7 703d 847d 0/2 auto-obsoleted due to no activity on 2024/12/07 01:30
▶ ▼ Fix bisection attempts (9)
Created Duration User Patch Repo Result
2025/05/28 19:35 12m bisect fix linux-6.1.y error job log
2025/04/24 14:19 1h55m bisect fix linux-6.1.y OK (0) job log log
2025/02/22 23:34 2h44m bisect fix linux-6.1.y OK (0) job log log
2024/12/29 04:40 2h00m bisect fix linux-6.1.y OK (0) job log log
2024/10/21 08:40 3h04m bisect fix linux-6.1.y OK (0) job log log
2024/09/20 04:31 1h45m bisect fix linux-6.1.y OK (0) job log log
2024/08/03 22:07 1h19m bisect fix linux-6.1.y OK (0) job log log
2024/06/08 12:48 1h13m bisect fix linux-6.1.y OK (0) job log log
2024/05/09 04:03 1h32m bisect fix linux-6.1.y OK (0) job log log

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...0: (1 GPs behind) idle=5c54/1/0x4000000000000000 softirq=7971/7972 fqs=5250
	(detected by 0, t=10502 jiffies, g=7201, q=465 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 3571 Comm: syz-executor366 Not tainted 6.1.84-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:match_held_lock+0x2/0xb0 kernel/locking/lockdep.c:5107
Code: e9 03 00 75 cf 48 c7 c7 60 ed eb 8a 48 c7 c6 a0 ed eb 8a e8 40 5f c8 f6 0f 0b eb b6 e8 e7 fa ff ff 0f 1f 80 00 00 00 00 55 53 <bd> 01 00 00 00 48 39 77 10 74 67 48 89 fb 81 7f 20 00 00 10 00 72
RSP: 0018:ffffc900001e0b48 EFLAGS: 00000087
RAX: 000000000000000a RBX: 0000000000000002 RCX: ffffc900001e0b03
RDX: ffff88801fca0ad8 RSI: ffff88806fada300 RDI: ffff88801fca0b30
RBP: ffffc900001e0ca0 R08: dffffc0000000000 R09: fffffbfff1ce6d46
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88801fca0b30
R13: 0000000000000002 R14: 000000000000000a R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbbd4ea62f0 CR3: 000000006f9b2000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 find_held_lock kernel/locking/lockdep.c:5152 [inline]
 __lock_release kernel/locking/lockdep.c:5337 [inline]
 lock_release+0x264/0xa20 kernel/locking/lockdep.c:5682
 __raw_spin_unlock include/linux/spinlock_api_smp.h:141 [inline]
 _raw_spin_unlock+0x12/0x40 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 advance_sched+0x68b/0x970 net/sched/sch_taprio.c:749
 __run_hrtimer kernel/time/hrtimer.c:1686 [inline]
 __hrtimer_run_queues+0x5e5/0xe50 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline]
 __sysvec_apic_timer_interrupt+0x156/0x580 arch/x86/kernel/apic/apic.c:1112
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1106
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653
RIP: 0010:check_kcov_mode kernel/kcov.c:184 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x32/0x60 kernel/kcov.c:207
Code: 44 e8 77 7e 65 8b 15 45 e8 77 7e f7 c2 00 01 ff 00 74 11 f7 c2 00 01 00 00 74 35 83 b9 1c 16 00 00 00 74 2c 8b 91 f8 15 00 00 <83> fa 02 75 21 48 8b 91 00 16 00 00 48 8b 32 48 8d 7e 01 8b 89 fc
RSP: 0018:ffffc90003bff6f8 EFLAGS: 00000246
RAX: ffffffff81cc3291 RBX: 1ffff1100295f2b8 RCX: ffff88801fca0000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90003bff8f0 R08: ffffffff81cc312b R09: fffff9400038b957
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888014af95c0
R13: 0000000000000000 R14: 00000000200b8000 R15: dffffc0000000000
 zap_pte_range mm/memory.c:1425 [inline]
 zap_pmd_range mm/memory.c:1574 [inline]
 zap_pud_range mm/memory.c:1603 [inline]
 zap_p4d_range mm/memory.c:1624 [inline]
 unmap_page_range+0xc81/0x2740 mm/memory.c:1645
 unmap_vmas+0x48b/0x640 mm/memory.c:1730
 exit_mmap+0x252/0x9f0 mm/mmap.c:3227
 __mmput+0x115/0x3c0 kernel/fork.c:1199
 exit_mm+0x226/0x300 kernel/exit.c:563
 do_exit+0x9f6/0x26a0 kernel/exit.c:856
 do_group_exit+0x202/0x2b0 kernel/exit.c:1019
 __do_sys_exit_group kernel/exit.c:1030 [inline]
 __se_sys_exit_group kernel/exit.c:1028 [inline]
 __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1028
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fbbd4e22fa9
Code: Unable to access opcode bytes at 0x7fbbd4e22f7f.
RSP: 002b:00007ffc04fd1a68 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fbbd4e22fa9
RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000
RBP: 00007fbbd4ea33b0 R08: ffffffffffffffb8 R09: 0000000100000000
R10: 0000000100000000 R11: 0000000000000246 R12: 00007fbbd4ea33b0
R13: 0000000000000000 R14: 00007fbbd4ea5ee0 R15: 00007fbbd4df3470
 </TASK>
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 2.342 msecs
NMI backtrace for cpu 1
CPU: 1 PID: 3571 Comm: syz-executor366 Not tainted 6.1.84-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:timerqueue_del+0x1f/0xf0 lib/timerqueue.c:55
Code: dc fd ff ff 0f 1f 80 00 00 00 00 55 41 57 41 56 41 55 41 54 53 49 89 f5 49 89 fe 48 bd 00 00 00 00 00 fc ff df e8 c1 3b 06 f7 <4d> 89 ec 49 c1 ec 03 41 80 3c 2c 00 74 08 4c 89 ef e8 3b b2 5d f7
RSP: 0018:ffffc900001e0d28 EFLAGS: 00000046
RAX: ffffffff8a844b2f RBX: 0000000000000001 RCX: ffff88801fca0000
RDX: 0000000080010002 RSI: ffff88806fada340 RDI: ffff8880b992a610
RBP: dffffc0000000000 R08: ffffffff8179b2fa R09: fffffbfff1ce6d46
R10: 0000000000000000 R11: dffffc0000000001 R12: 1bc16d674eda5f30
R13: ffff88806fada340 R14: ffff8880b992a610 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbbd4ea62f0 CR3: 000000006f9b2000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 __remove_hrtimer kernel/time/hrtimer.c:1117 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1666 [inline]
 __hrtimer_run_queues+0x409/0xe50 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline]
 __sysvec_apic_timer_interrupt+0x156/0x580 arch/x86/kernel/apic/apic.c:1112
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1106
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653
RIP: 0010:check_kcov_mode kernel/kcov.c:184 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x32/0x60 kernel/kcov.c:207
Code: 44 e8 77 7e 65 8b 15 45 e8 77 7e f7 c2 00 01 ff 00 74 11 f7 c2 00 01 00 00 74 35 83 b9 1c 16 00 00 00 74 2c 8b 91 f8 15 00 00 <83> fa 02 75 21 48 8b 91 00 16 00 00 48 8b 32 48 8d 7e 01 8b 89 fc
RSP: 0018:ffffc90003bff6f8 EFLAGS: 00000246
RAX: ffffffff81cc3291 RBX: 1ffff1100295f2b8 RCX: ffff88801fca0000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90003bff8f0 R08: ffffffff81cc312b R09: fffff9400038b957
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888014af95c0
R13: 0000000000000000 R14: 00000000200b8000 R15: dffffc0000000000
 zap_pte_range mm/memory.c:1425 [inline]
 zap_pmd_range mm/memory.c:1574 [inline]
 zap_pud_range mm/memory.c:1603 [inline]
 zap_p4d_range mm/memory.c:1624 [inline]
 unmap_page_range+0xc81/0x2740 mm/memory.c:1645
 unmap_vmas+0x48b/0x640 mm/memory.c:1730
 exit_mmap+0x252/0x9f0 mm/mmap.c:3227
 __mmput+0x115/0x3c0 kernel/fork.c:1199
 exit_mm+0x226/0x300 kernel/exit.c:563
 do_exit+0x9f6/0x26a0 kernel/exit.c:856
 do_group_exit+0x202/0x2b0 kernel/exit.c:1019
 __do_sys_exit_group kernel/exit.c:1030 [inline]
 __se_sys_exit_group kernel/exit.c:1028 [inline]
 __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1028
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fbbd4e22fa9
Code: Unable to access opcode bytes at 0x7fbbd4e22f7f.
RSP: 002b:00007ffc04fd1a68 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fbbd4e22fa9
RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000
RBP: 00007fbbd4ea33b0 R08: ffffffffffffffb8 R09: 0000000100000000
R10: 0000000100000000 R11: 0000000000000246 R12: 00007fbbd4ea33b0
R13: 0000000000000000 R14: 00007fbbd4ea5ee0 R15: 00007fbbd4df3470
 </TASK>

Crashes (34):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/04/04 06:30 linux-6.1.y 347385861c50 51c4dcff .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2024/03/28 05:00 linux-6.1.y e5cd595e23c1 120789fd .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2024/02/25 03:23 linux-6.1.y 81e1dc2f7001 8d446f15 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2024/02/23 04:57 linux-6.1.y 8b4118fabd6e 8d446f15 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2026/07/17 15:19 linux-6.1.y 090666d3cc90 7f27c57a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2026/07/09 07:33 linux-6.1.y 090666d3cc90 b9f1ceaa .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2026/06/14 03:44 linux-6.1.y 228da13e907e 1d2f3589 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_exit_group
2026/06/13 10:58 linux-6.1.y 228da13e907e 1d2f3589 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2026/05/20 01:48 linux-6.1.y c27210688955 0909d65f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2026/04/21 00:12 linux-6.1.y 7c87defbd336 e65da4ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2026/04/14 21:28 linux-6.1.y 8e8fc038cad5 362d1323 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2026/04/12 08:50 linux-6.1.y 8e8fc038cad5 38c8e246 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2026/04/08 03:50 linux-6.1.y 1989cd3d56e2 2c961e87 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2026/03/25 05:17 linux-6.1.y f2ddafa93a25 74e70d19 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2026/02/18 02:13 linux-6.1.y 8ce36b2849ef 06ec4f7b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2026/02/06 05:43 linux-6.1.y cd9b81672742 f03c4191 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2026/01/29 07:54 linux-6.1.y cd9b81672742 0adc945e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2026/01/22 21:40 linux-6.1.y cd9b81672742 82c9c083 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_exit_group
2025/12/13 21:32 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2025/10/12 05:45 linux-6.1.y 882efbdd9d34 ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_exit_group
2025/09/25 11:16 linux-6.1.y 7b34dc04e4ff 0abd0691 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2025/08/09 16:35 linux-6.1.y 3594f306da12 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2025/07/14 12:24 linux-6.1.y dfc486ec9cce d8fc7335 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2025/06/25 08:36 linux-6.1.y 58485ff1a74f 26d77996 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2025/05/31 13:31 linux-6.1.y da3c5173c55f 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2025/05/28 21:22 linux-6.1.y da3c5173c55f 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2025/03/21 01:49 linux-6.1.y 344a09659766 62330552 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2025/01/23 20:16 linux-6.1.y 75cefdf153f5 521b0ce3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2024/11/12 22:08 linux-6.1.y d7039b844a1c 62026c85 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2024/08/17 18:12 linux-6.1.y 117ac406ba90 dbc93b08 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2024/06/24 05:10 linux-6.1.y eb44d83053d6 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2024/03/14 22:54 linux-6.1.y 61adba85cc40 d615901c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2024/01/25 22:20 linux-6.1.y 8fd7f4462453 cc4a4020 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
2024/01/23 11:04 linux-6.1.y 8fd7f4462453 1c0ecc51 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
* Struck through repros no longer work on HEAD.