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INFO: rcu detected stall in sys_execve

Status: upstream: reported on 2025/01/23 20:17
Reported-by: syzbot+c8f053523131494fd85d@syzkaller.appspotmail.com
First crash: 134d, last: 66d
▶ ▼ Similar bugs (7)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_execve kernel 11 2012d 2013d 0/28 closed as invalid on 2019/12/04 14:04
upstream INFO: rcu detected stall in sys_execve (6) mm syz done 50 2d13h 263d 0/28 upstream: reported syz repro on 2024/09/17 11:35
upstream INFO: rcu detected stall in sys_execve (3) kernel 1 1977d 1977d 0/28 closed as invalid on 2020/01/09 08:13
upstream INFO: rcu detected stall in sys_execve (2) kernel 1 1977d 1977d 0/28 closed as invalid on 2020/01/08 05:23
upstream INFO: rcu detected stall in sys_execve (5) tomoyo 2 572d 576d 0/28 auto-obsoleted due to no activity on 2024/02/10 22:46
upstream INFO: rcu detected stall in sys_execve (4) mm 1 1138d 1138d 0/28 auto-closed as invalid on 2022/06/25 07:48
linux-5.15 BUG: soft lockup in sys_execve 1 211d 211d 0/3 auto-obsoleted due to no activity on 2025/02/15 21:26

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 GPs behind) idle=c8b4/1/0x4000000000000000 softirq=17198/17200 fqs=15
	(detected by 1, t=10502 jiffies, g=21541, q=303 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 6091 Comm: dhcpcd-run-hook Not tainted 6.1.132-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:__lock_acquire+0xdcd/0x1f80 kernel/locking/lockdep.c:-1
Code: 84 c0 0f 85 62 0c 00 00 8b 1b 48 8b 44 24 30 0f b6 04 38 84 c0 0f 85 76 0c 00 00 48 8b 44 24 08 33 18 f7 c3 00 60 00 00 74 0d <41> bd 01 00 00 00 49 c7 c7 ff ff ff ff 48 8b 44 24 30 0f b6 04 38
RSP: 0018:ffffc90000007a80 EFLAGS: 00000006
RAX: ffff888020abe4e0 RBX: 000000000008404f RCX: ffff888020abe420
RDX: 0000000000000000 RSI: 0000000000000008 RDI: dffffc0000000000
RBP: ffff888020abe4c0 R08: dffffc0000000000 R09: fffffbfff225764e
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888020abe418
R13: 0000000000000000 R14: ffff888020abe4e0 R15: 85c357eb5e4a956c
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f69bcb8bb10 CR3: 00000000557d8000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline]
 _raw_spin_lock_irq+0xcf/0x110 kernel/locking/spinlock.c:170
 __run_hrtimer kernel/time/hrtimer.c:1695 [inline]
 __hrtimer_run_queues+0x6d3/0xe50 kernel/time/hrtimer.c:1755
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1817
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
 __sysvec_apic_timer_interrupt+0x158/0x5b0 arch/x86/kernel/apic/apic.c:1124
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0x9b/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:lock_acquire+0x26f/0x5a0 kernel/locking/lockdep.c:5666
Code: 2b 00 74 08 4c 89 f7 e8 af 54 77 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25
RSP: 0018:ffffc9000c27f220 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff9200184fe50 RCX: ffffffff816b7272
RDX: dffffc0000000000 RSI: ffffffff8b0c2f40 RDI: ffffffff8b5f70e0
RBP: ffffc9000c27f378 R08: dffffc0000000000 R09: fffffbfff225764d
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200184fe4c
R13: dffffc0000000000 R14: ffffc9000c27f280 R15: 0000000000000246
 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
 _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:351 [inline]
 zap_pte_range mm/memory.c:1417 [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+0xacc/0x2740 mm/memory.c:1645
 unmap_vmas+0x48b/0x640 mm/memory.c:1730
 exit_mmap+0x249/0x980 mm/mmap.c:3238
 __mmput+0x115/0x3c0 kernel/fork.c:1200
 exec_mmap+0x4fa/0x5b0 fs/exec.c:1040
 begin_new_exec+0xb65/0x2090 fs/exec.c:1299
 load_elf_binary+0x955/0x2720 fs/binfmt_elf.c:1002
 search_binary_handler fs/exec.c:1764 [inline]
 exec_binprm fs/exec.c:1805 [inline]
 bprm_execve+0x96a/0x18a0 fs/exec.c:1874
 do_execveat_common+0x580/0x720 fs/exec.c:1979
 do_execve fs/exec.c:2053 [inline]
 __do_sys_execve fs/exec.c:2129 [inline]
 __se_sys_execve fs/exec.c:2124 [inline]
 __x64_sys_execve+0x8e/0xa0 fs/exec.c:2124
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f69bca96ef7
Code: Unable to access opcode bytes at 0x7f69bca96ecd.
RSP: 002b:00007ffdb2cc9578 EFLAGS: 00000246 ORIG_RAX: 000000000000003b
RAX: ffffffffffffffda RBX: 0000555f1a9e4110 RCX: 00007f69bca96ef7
RDX: 0000555f1a9e4138 RSI: 0000555f1a9e4110 RDI: 0000555f1a9da388
RBP: 0000555f1a9da388 R08: 0000555f1a9da391 R09: 00007ffdb2ccde08
R10: 000000000000002f R11: 0000000000000246 R12: 0000555f1a9e4138
R13: 00007f69bcc44904 R14: 0000555f1a9e4138 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread starved for 10470 jiffies! g21541 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:26200 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6561
 schedule+0xbf/0x180 kernel/sched/core.c:6637
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905
 kthread+0x28d/0x320 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: 1 PID: 6095 Comm: syz.1.560 Not tainted 6.1.132-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:csd_lock_wait kernel/smp.c:424 [inline]
RIP: 0010:smp_call_function_many_cond+0x1fae/0x3460 kernel/smp.c:998
Code: 2f 44 89 ee 83 e6 01 31 ff e8 2e 4b 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 0a e8 b9 47 0b 00 e9 1b ff ff ff f3 90 <42> 0f b6 04 2b 84 c0 75 14 41 f7 07 01 00 00 00 0f 84 fe fe ff ff
RSP: 0018:ffffc9000c37f9c0 EFLAGS: 00000246
RAX: ffffffff817f62b9 RBX: 1ffff110171c858d RCX: 0000000000080000
RDX: ffffc9000d7e1000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc9000c37fd88 R08: ffffffff817f6282 R09: fffffbfff2257672
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000800000000
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8880b8e42c68
FS:  00007f2e703f16c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2d91fffc CR3: 00000000316e6000 CR4: 00000000003526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1166
 on_each_cpu include/linux/smp.h:71 [inline]
 hardware_enable_all+0x77/0x120 virt/kvm/kvm_main.c:5164
 kvm_create_vm virt/kvm/kvm_main.c:1223 [inline]
 kvm_dev_ioctl_create_vm virt/kvm/kvm_main.c:5010 [inline]
 kvm_dev_ioctl+0x10db/0x1860 virt/kvm/kvm_main.c:5052
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f2e6f58d169
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:00007f2e703f1038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f2e6f7a5fa0 RCX: 00007f2e6f58d169
RDX: 0000000000000000 RSI: 000000000000ae01 RDI: 0000000000000003
RBP: 00007f2e6f60e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f2e6f7a5fa0 R15: 00007ffcb04f9e28
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/04/02 07:17 linux-6.1.y 8e60a714ba3b c799dfdd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_execve
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_execve
* Struck through repros no longer work on HEAD.