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INFO: rcu detected stall in sys_process_vm_readv

Status: upstream: reported on 2024/07/07 14:50
Reported-by: syzbot+24153f1bae0a75fc6476@syzkaller.appspotmail.com
First crash: 102d, last: 89d
▶ ▼ Similar bugs (5)
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 768d 768d 0/28 auto-obsoleted due to no activity on 2022/12/09 23:02
upstream INFO: rcu detected stall in sys_process_vm_readv (3) mm cgroups 6 302d 478d 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 (2) 4 17d 70d 0/3 upstream: reported on 2024/08/08 22:49
linux-5.15 INFO: rcu detected stall in sys_process_vm_readv 2 329d 372d 0/3 auto-obsoleted due to no activity on 2024/03/02 07:32
upstream INFO: rcu detected stall in sys_process_vm_readv cgroups mm 1 906d 906d 0/28 auto-closed as invalid on 2022/06/24 21:29

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P46/1:b..l P3767/1:b..l P3754/1:b..l
	(detected by 1, t=10502 jiffies, g=6773, q=517 ncpus=2)
task:kworker/u4:12   state:R  running task     stack:26136 pid:3754  ppid:2      flags:0x00004000
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6561
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6873
 irqentry_exit+0x53/0x80 kernel/entry/common.c:439
 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:658
RIP: 0010:batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:756 [inline]
RIP: 0010:batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:826 [inline]
RIP: 0010:batadv_iv_ogm_schedule+0x4d2/0x1090 net/batman-adv/bat_iv_ogm.c:869
Code: be 19 03 00 00 48 c7 c2 60 0b 04 8c e8 97 75 13 f7 4c 89 f8 48 c1 e8 03 42 80 3c 30 00 74 08 4c 89 ff e8 11 cd 8a f7 49 8b 1f <48> 85 db 0f 84 69 01 00 00 48 81 c3 38 fe ff ff 0f 84 5c 01 00 00
RSP: 0018:ffffc90005217a60 EFLAGS: 00000246
RAX: 1ffff1100bd44b58 RBX: 0000000000000000 RCX: ffff888020fb3b80
RDX: 0000000000000000 RSI: ffffffff8b3d4880 RDI: ffffffff8b3d4840
RBP: ffffc90005217b98 R08: ffffffff8a57547f R09: fffffbfff2093845
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88801ed6e800
R13: ffff88805e999340 R14: dffffc0000000000 R15: ffff88805ea25ac0
 batadv_iv_send_outstanding_bat_ogm_packet+0x6fa/0x800 net/batman-adv/bat_iv_ogm.c:1713
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
task:syz.0.39        state:R  running task     stack:24168 pid:3767  ppid:3550   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6561
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6873
 irqentry_exit+0x53/0x80 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653
RIP: 0010:lock_acquire+0x26f/0x5a0 kernel/locking/lockdep.c:5666
Code: 2b 00 74 08 4c 89 f7 e8 cf b2 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:ffffc900052b7220 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff92000a56e50 RCX: 1ffff92000a56df0
RDX: dffffc0000000000 RSI: ffffffff8aec13c0 RDI: ffffffff8b3d48a0
RBP: ffffc900052b7370 R08: dffffc0000000000 R09: fffffbfff2093845
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000a56e4c
R13: dffffc0000000000 R14: ffffc900052b7280 R15: 0000000000000246
 rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 rcu_read_lock include/linux/rcupdate.h:791 [inline]
 get_mem_cgroup_from_mm+0x51/0x290 mm/memcontrol.c:1036
 __mem_cgroup_charge+0x12/0x80 mm/memcontrol.c:6919
 mem_cgroup_charge include/linux/memcontrol.h:672 [inline]
 wp_page_copy+0x3f3/0x18c0 mm/memory.c:3158
 handle_pte_fault mm/memory.c:5031 [inline]
 __handle_mm_fault mm/memory.c:5155 [inline]
 handle_mm_fault+0x2525/0x5340 mm/memory.c:5276
 do_user_addr_fault arch/x86/mm/fault.c:1340 [inline]
 handle_page_fault arch/x86/mm/fault.c:1431 [inline]
 exc_page_fault+0x26f/0x620 arch/x86/mm/fault.c:1487
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:570
RIP: 0010:copy_user_enhanced_fast_string+0xa/0x40 arch/x86/lib/copy_user_64.S:166
Code: ff c9 75 f2 89 d1 c1 e9 03 83 e2 07 f3 48 a5 89 d1 f3 a4 31 c0 0f 01 ca c3 8d 0c ca 89 ca eb 20 0f 01 cb 83 fa 40 72 38 89 d1 <f3> a4 31 c0 0f 01 ca c3 89 ca eb 0a 66 2e 0f 1f 84 00 00 00 00 00
RSP: 0018:ffffc900052b7970 EFLAGS: 00050206
RAX: ffffffff84365a01 RBX: 00007fffffffe000 RCX: 0000000000000e80
RDX: 0000000000001000 RSI: ffff88800fd86180 RDI: 0000000020e1c000
RBP: ffffc900052b7af8 R08: dffffc0000000000 R09: ffffed1001fb0e00
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000001000
R13: 0000000000000000 R14: 0000000020e1be80 R15: ffff88800fd86000
 copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline]
 raw_copy_to_user arch/x86/include/asm/uaccess_64.h:58 [inline]
 copyout+0xd8/0x120 lib/iov_iter.c:170
 _copy_to_iter+0x4a6/0x1000 lib/iov_iter.c:527
 copy_page_to_iter+0xac/0x170 lib/iov_iter.c:725
 process_vm_rw_pages mm/process_vm_access.c:45 [inline]
 process_vm_rw_single_vec mm/process_vm_access.c:117 [inline]
 process_vm_rw_core mm/process_vm_access.c:215 [inline]
 process_vm_rw+0x886/0xcc0 mm/process_vm_access.c:283
 __do_sys_process_vm_readv mm/process_vm_access.c:295 [inline]
 __se_sys_process_vm_readv mm/process_vm_access.c:291 [inline]
 __x64_sys_process_vm_readv+0xdc/0xf0 mm/process_vm_access.c:291
 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: 0033:0x7f11f3375b59
RSP: 002b:00007f11f40f6048 EFLAGS: 00000246 ORIG_RAX: 0000000000000136
RAX: ffffffffffffffda RBX: 00007f11f3505f60 RCX: 00007f11f3375b59
RDX: 0000000000000002 RSI: 0000000020008400 RDI: 000000000000001d
RBP: 00007f11f33e4e5d R08: 0000000000000286 R09: 0000000000000000
R10: 0000000020008640 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f11f3505f60 R15: 00007ffcdc6ec2a8
 </TASK>
task:kworker/u4:3    state:R  running task     stack:23384 pid:46    ppid:2      flags:0x00004000
Workqueue: netns cleanup_net
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6561
 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6730
 preempt_schedule+0xd9/0xe0 kernel/sched/core.c:6754
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
 __local_bh_enable_ip+0x175/0x1f0 kernel/softirq.c:403
 spin_unlock_bh include/linux/spinlock.h:396 [inline]
 __fib6_clean_all+0x323/0x4b0 net/ipv6/ip6_fib.c:2262
 rt6_sync_down_dev net/ipv6/route.c:4902 [inline]
 rt6_disable_ip+0x14c/0x890 net/ipv6/route.c:4907
 addrconf_ifdown+0x154/0x1b90 net/ipv6/addrconf.c:3781
 addrconf_notify+0x3ec/0xf60
 notifier_call_chain kernel/notifier.c:87 [inline]
 raw_notifier_call_chain+0xd0/0x170 kernel/notifier.c:455
 call_netdevice_notifiers_info net/core/dev.c:1970 [inline]
 call_netdevice_notifiers_extack net/core/dev.c:2008 [inline]
 call_netdevice_notifiers net/core/dev.c:2022 [inline]
 dev_close_many+0x37c/0x530 net/core/dev.c:1570
 unregister_netdevice_many+0x4f7/0x17a0 net/core/dev.c:10856
 ip6gre_exit_batch_net+0x415/0x460 net/ipv6/ip6_gre.c:1669
 ops_exit_list net/core/net_namespace.c:177 [inline]
 cleanup_net+0x763/0xb60 net/core/net_namespace.c:604
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: rcu_preempt kthread starved for 10029 jiffies! g6773 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:25528 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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt drivers/acpi/processor_idle.c:111 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:567

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/07/20 22:49 linux-6.1.y 9b3f9a5b12dc b88348e9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_process_vm_readv
2024/07/07 14:50 linux-6.1.y 7753af06eebf 2a40360c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_process_vm_readv
* Struck through repros no longer work on HEAD.