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INFO: rcu detected stall in sys_process_vm_readv (5)

Status: auto-obsoleted due to no activity on 2025/04/25 18:06
Subsystems: mm
[Documentation on labels]
First crash: 137d, last: 137d
▶ ▼ Similar bugs (9)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_process_vm_readv (2) mm 1 1005d 1005d 0/28 auto-obsoleted due to no activity on 2022/12/09 23:02
linux-6.1 INFO: rcu detected stall in sys_process_vm_readv (2) 1 130d 130d 0/3 auto-obsoleted due to no activity on 2025/05/13 07:10
upstream INFO: rcu detected stall in sys_process_vm_readv (3) mm cgroups 6 539d 715d 0/28 auto-obsoleted due to no activity on 2024/03/20 00:08
linux-5.15 INFO: rcu detected stall in sys_process_vm_readv (3) 1 97d 97d 0/3 upstream: reported on 2025/03/06 17:14
linux-5.15 INFO: rcu detected stall in sys_process_vm_readv (2) 4 254d 307d 0/3 auto-obsoleted due to no activity on 2025/01/09 01:58
linux-5.15 INFO: rcu detected stall in sys_process_vm_readv 2 567d 610d 0/3 auto-obsoleted due to no activity on 2024/03/02 07:32
linux-6.1 INFO: rcu detected stall in sys_process_vm_readv 2 326d 339d 0/3 auto-obsoleted due to no activity on 2024/10/28 22:50
upstream INFO: rcu detected stall in sys_process_vm_readv cgroups mm 1 1143d 1143d 0/28 auto-closed as invalid on 2022/06/24 21:29
upstream INFO: rcu detected stall in sys_process_vm_readv (4) mm 28 264d 400d 0/28 auto-obsoleted due to no activity on 2024/11/29 20:49

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P14653/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=59597, q=403 ncpus=2)
task:syz.2.2326      state:R  running task     stack:22840 pid:14653 tgid:14652 ppid:10589  flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5377 [inline]
 __schedule+0x181a/0x4b90 kernel/sched/core.c:6764
 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7086
 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:rcu_read_unlock include/linux/rcupdate.h:878 [inline]
RIP: 0010:count_memcg_events_mm include/linux/memcontrol.h:998 [inline]
RIP: 0010:count_memcg_event_mm+0x334/0x420 include/linux/memcontrol.h:1004
Code: e2 2e b5 ff 4c 8b 6c 24 18 eb 1f e8 d6 2e b5 ff e8 91 84 e2 09 4d 85 f6 74 84 e8 c7 2e b5 ff fb 49 be 00 00 00 00 00 fc ff df <e8> 27 8b e2 09 89 c3 31 ff 89 c6 e8 ec 32 b5 ff 85 db 74 10 e8 23
RSP: 0018:ffffc90004f0f500 EFLAGS: 00000246
RAX: ffffffff820a1919 RBX: 0000000000000000 RCX: 0000000000080000
RDX: ffffc9001a239000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc90004f0f5d0 R08: ffffffff820a1889 R09: 1ffffffff285830f
R10: dffffc0000000000 R11: fffffbfff2858310 R12: 0000000000000046
R13: ffffffff820a1684 R14: dffffc0000000000 R15: 1ffff920009e1ea4
 mm_account_fault mm/memory.c:5997 [inline]
 handle_mm_fault+0x1791/0x1c60 mm/memory.c:6157
 do_user_addr_fault arch/x86/mm/fault.c:1389 [inline]
 handle_page_fault arch/x86/mm/fault.c:1481 [inline]
 exc_page_fault+0x2b9/0x8b0 arch/x86/mm/fault.c:1539
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0010:rep_movs_alternative+0x4a/0x70 arch/x86/lib/copy_user_64.S:71
Code: 75 f1 c3 cc cc cc cc 66 0f 1f 84 00 00 00 00 00 48 8b 06 48 89 07 48 83 c6 08 48 83 c7 08 83 e9 08 74 df 83 f9 08 73 e8 eb c9 <f3> a4 c3 cc cc cc cc 48 89 c8 48 c1 e9 03 83 e0 07 f3 48 a5 89 c1
RSP: 0018:ffffc90004f0f958 EFLAGS: 00050206
RAX: ffff8880131a5001 RBX: 0000000000001000 RCX: 0000000000000e80
RDX: 0000000000000000 RSI: ffff8880131a5180 RDI: 0000000020698000
RBP: ffffc90004f0fad8 R08: ffff8880131a5fff R09: 1ffff11002634bff
R10: dffffc0000000000 R11: ffffed1002634c00 R12: 0000000000000000
R13: 1ffff920009e1f40 R14: ffff8880131a5000 R15: 0000000020698e80
 copy_user_generic arch/x86/include/asm/uaccess_64.h:126 [inline]
 raw_copy_to_user arch/x86/include/asm/uaccess_64.h:147 [inline]
 copy_to_user_iter lib/iov_iter.c:25 [inline]
 iterate_iovec include/linux/iov_iter.h:52 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:302 [inline]
 iterate_and_advance include/linux/iov_iter.h:328 [inline]
 _copy_to_iter+0x4d5/0x1c50 lib/iov_iter.c:185
 copy_page_to_iter+0xb1/0x160 lib/iov_iter.c:362
 process_vm_rw_pages mm/process_vm_access.c:45 [inline]
 process_vm_rw_single_vec mm/process_vm_access.c:118 [inline]
 process_vm_rw_core mm/process_vm_access.c:216 [inline]
 process_vm_rw+0x7ea/0xc50 mm/process_vm_access.c:284
 __do_sys_process_vm_readv mm/process_vm_access.c:296 [inline]
 __se_sys_process_vm_readv mm/process_vm_access.c:292 [inline]
 __x64_sys_process_vm_readv+0xe0/0x100 mm/process_vm_access.c:292
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f836e58cd29
RSP: 002b:00007f836f368038 EFLAGS: 00000246 ORIG_RAX: 0000000000000136
RAX: ffffffffffffffda RBX: 00007f836e7a5fa0 RCX: 00007f836e58cd29
RDX: 0000000000000002 RSI: 0000000020008400 RDI: 0000000000000275
RBP: 00007f836e60e2a0 R08: 00000000000002aa R09: 0000000000000000
R10: 0000000020008640 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f836e7a5fa0 R15: 00007fff48a26788
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g59597 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=49305
rcu: rcu_preempt kthread starved for 10502 jiffies! g59597 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:23576 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5377 [inline]
 __schedule+0x181a/0x4b90 kernel/sched/core.c:6764
 __schedule_loop kernel/sched/core.c:6841 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6856
 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2024
 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2226
 kthread+0x7a9/0x920 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
 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 UID: 0 PID: 14661 Comm: syz.0.2327 Not tainted 6.13.0-syzkaller-07078-gb46c89c08f41 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xc7/0x140 kernel/locking/spinlock.c:194
Code: 4c 89 f7 e8 fb 04 34 f6 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 ee 03 34 f6 f6 44 24 21 02 <75> 52 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 e8 f3 1c 9e f5
RSP: 0018:ffffc90000007ca0 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 1ffff92000000f98 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff8880b862c500
RBP: ffffc90000007d30 R08: ffff8880b862c503 R09: 1ffff110170c58a0
R10: dffffc0000000000 R11: ffffed10170c58a1 R12: dffffc0000000000
R13: 1ffff92000000f94 R14: ffffc90000007cc0 R15: 0000000000000046
FS:  0000555590d48500(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020698000 CR3: 00000000346c2000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 __run_hrtimer kernel/time/hrtimer.c:1734 [inline]
 __hrtimer_run_queues+0x477/0xd30 kernel/time/hrtimer.c:1802
 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1864
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
 __sysvec_apic_timer_interrupt+0x110/0x420 arch/x86/kernel/apic/apic.c:1055
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:202
Code: 90 f3 0f 1e fa 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 5a 74 ab f5 48 89 df e8 92 bb ac f5 e8 dd 9f d7 f5 fb bf 01 00 00 00 <e8> 52 1c 9e f5 65 8b 05 13 73 14 74 85 c0 74 06 5b c3 cc cc cc cc
RSP: 0018:ffffc90004547c70 EFLAGS: 00000282
RAX: 2d3e941a63ccd800 RBX: ffff88802f963780 RCX: ffffffff9a3c8903
RDX: dffffc0000000000 RSI: ffffffff8c0a8f80 RDI: 0000000000000001
RBP: ffffc90004547db0 R08: ffffffff901a5c37 R09: 1ffffffff2034b86
R10: dffffc0000000000 R11: fffffbfff2034b87 R12: 0000000000000021
R13: 1ffff11005f2c783 R14: ffff88802f963c18 R15: ffff88802f963780
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 get_signal+0x14ee/0x1750 kernel/signal.c:3039
 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0xce/0x340 kernel/entry/common.c:218
 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4e74f8cd29
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:00007ffcf7bca538 EFLAGS: 00000246
RAX: 0000000000000001 RBX: 00007f4e751a5fa8 RCX: 00007f4e74f8cd29
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f4e751a5fa8
RBP: 00007f4e751a5fac R08: 0000000000000003 R09: 00007ffcf7bca82f
R10: 00007f4e751a5fa0 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4e751a5fa0 R14: 0000000000000004 R15: 0000000000001c9e
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/01/25 17:57 upstream b46c89c08f41 9fbd772e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in sys_process_vm_readv
* Struck through repros no longer work on HEAD.