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INFO: rcu detected stall in preempt_schedule_thunk

Status: auto-obsoleted due to no activity on 2024/11/01 23:14
Subsystems: kernel
[Documentation on labels]
First crash: 204d, last: 162d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: rcu detected stall in preempt_schedule_thunk 1 240d 240d 0/3 auto-obsoleted due to no activity on 2024/08/25 23:34

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 1, t=10502 jiffies, g=201813, q=285 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10494 (4295138161-4295127667), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10495 jiffies! g201813 f0x2 RCU_GP_CLEANUP(7) ->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:26448 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5408 [inline]
 __schedule+0x1796/0x49d0 kernel/sched/core.c:6745
 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7067
 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:constant_test_bit arch/x86/include/asm/bitops.h:206 [inline]
RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:238 [inline]
RIP: 0010:tif_need_resched include/linux/thread_info.h:184 [inline]
RIP: 0010:need_resched include/linux/sched.h:2110 [inline]
RIP: 0010:preempt_schedule_common+0x11/0xd0 kernel/sched/core.c:6932
Code: ff 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 41 57 41 56 53 49 bf 00 00 00 00 00 fc ff df eb 0d <48> f7 03 08 00 00 00 0f 84 9c 00 00 00 65 ff 05 13 7d 7d 74 65 8b
RSP: 0018:ffffc90000167bc0 EFLAGS: 00000246
RAX: 1ffff11002e51000 RBX: ffff888017288000 RCX: 1ffff9200002cf54
RDX: dffffc0000000000 RSI: ffffffff8bcabb80 RDI: ffff8880172895f8
RBP: ffffc90000167c68 R08: ffffffff8fac20ef R09: 1ffffffff1f5841d
R10: dffffc0000000000 R11: fffffbfff1f5841e R12: 1ffff9200002cf80
R13: ffffffff8e338c00 R14: ffffffff8b865731 R15: dffffc0000000000
 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6948
 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12
 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
 _raw_spin_unlock_irq+0x44/0x50 kernel/locking/spinlock.c:202
 rcu_gp_cleanup+0x5b2/0x1030 kernel/rcu/tree.c:2115
 rcu_gp_kthread+0xb5/0x3b0 kernel/rcu/tree.c:2206
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 28711 Comm: syz-executor.0 Not tainted 6.10.0-rc4-syzkaller-00301-g5f583a3162ff #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
RIP: 0010:__sanitizer_cov_trace_cmp4+0x0/0x90 kernel/kcov.c:277
Code: 10 48 89 74 0a 18 4c 89 44 0a 20 c3 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 4c 8b 04 24 65 48 8b 14 25 80 d4 03 00 65 8b 05 10 ae
RSP: 0018:ffffc90008cb76e0 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 000000000000005c RCX: 0000000000040000
RDX: ffffc90012fa2000 RSI: 000000000000005f RDI: 000000000000005c
RBP: dffffc0000000000 R08: ffffffff8b7508ec R09: 1ffff11017287e1a
R10: dffffc0000000000 R11: ffffed1017287e1b R12: ffff88804e122308
R13: ffff8880b943f0a8 R14: ffff88804e122308 R15: 000000000000005f
FS:  00007f0233b726c0(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2e824000 CR3: 000000004e620000 CR4: 00000000003506f0
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 plist_add+0x197/0x490 lib/plist.c:98
 enqueue_pushable_task+0x11a/0x3d0 kernel/sched/rt.c:391
 __pick_next_task+0xdb/0x2c0 kernel/sched/core.c:6050
 pick_next_task kernel/sched/core.c:6119 [inline]
 __schedule+0x729/0x49d0 kernel/sched/core.c:6701
 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7067
 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:preempt_schedule_common+0x18/0xd0 kernel/sched/core.c:6932
Code: 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 41 57 41 56 53 49 bf 00 00 00 00 00 fc ff df eb 0d 48 f7 03 08 00 00 00 <0f> 84 9c 00 00 00 65 ff 05 13 7d 7d 74 65 8b 05 0c 7d 7d 74 25 ff
RSP: 0018:ffffc90008cb7b60 EFLAGS: 00000202
RAX: 1ffff1100c0af780 RBX: ffff88806057bc00 RCX: 1ffff92001196f48
RDX: dffffc0000000000 RSI: ffffffff8bcabb80 RDI: ffff88806057d1f8
RBP: ffffc90008cb7c08 R08: ffffffff8fac20ef R09: 1ffffffff1f5841d
R10: dffffc0000000000 R11: fffffbfff1f5841e R12: 1ffff92001196f74
R13: 1ffff11005ffc1bb R14: ffffffff8b865731 R15: dffffc0000000000
 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6948
 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12
 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
 _raw_spin_unlock_irq+0x44/0x50 kernel/locking/spinlock.c:202
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 get_signal+0x14dd/0x1740 kernel/signal.c:2912
 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0xc9/0x370 kernel/entry/common.c:218
 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0232e7d0a9
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:00007f0233b720c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000090
RAX: 0000000000000000 RBX: 00007f0232fb4050 RCX: 00007f0232e7d0a9
RDX: 0000000020000200 RSI: 0000000000000002 RDI: 0000000000000000
RBP: 00007f0232eec074 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f0232fb4050 R15: 00007ffd7eb60de8
 </TASK>

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/23 14:04 upstream 5f583a3162ff edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in preempt_schedule_thunk
2024/08/03 23:05 upstream 17712b7ea075 1786a2a8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 INFO: rcu detected stall in preempt_schedule_thunk
2024/07/29 05:43 linux-next 931a3b3bccc9 46eb10b7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in preempt_schedule_thunk
2024/07/28 13:05 linux-next 668d33c9ff92 46eb10b7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in preempt_schedule_thunk
* Struck through repros no longer work on HEAD.