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INFO: rcu detected stall in sys_symlink (5)

Status: closed as invalid on 2025/02/03 10:48
Subsystems: mm fs
[Documentation on labels]
First crash: 251d, last: 103d
Cause bisection: the cause commit could be any of (bisect log):
  781773e3b680 sched/fair: Implement ENQUEUE_DELAYED
  a1c446611e31 sched,freezer: Mark TASK_FROZEN special
  e1459a50ba31 sched: Teach dequeue_task() about special task states
  f12e148892ed sched/fair: Prepare pick_next_task() for delayed dequeue
  152e11f6df29 sched/fair: Implement delayed dequeue
  2e0199df252a sched/fair: Prepare exit/cleanup paths for delayed_dequeue
  54a58a787791 sched/fair: Implement DELAY_ZERO
  
Fix bisection: fixed by (bisect log) :
commit 66951e4860d3c688bfa550ea4a19635b57e00eca
Author: Peter Zijlstra <peterz@infradead.org>
Date: Mon Jan 13 12:50:11 2025 +0000

  sched/fair: Fix update_cfs_group() vs DELAY_DEQUEUE

  
Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_symlink (3) kernel 4 1891d 1891d 0/28 closed as invalid on 2020/01/09 08:13
upstream INFO: rcu detected stall in sys_symlink (2) cgroups mm 2 1891d 1891d 0/28 closed as invalid on 2020/01/08 05:23
upstream INFO: rcu detected stall in sys_symlink kernel 17 1926d 1927d 0/28 closed as invalid on 2019/12/04 14:14
upstream INFO: rcu detected stall in sys_symlink (4) bpf 11 1154d 1258d 0/28 closed as invalid on 2022/02/08 09:50
Last patch testing requests (2)
Created Duration User Patch Repo Result
2024/11/27 19:42 31m edumazet@google.com upstream report log
2024/10/25 03:03 4h44m retest repro upstream report log

Sample crash report:
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P6590/1:b..l P5851/1:b..l
rcu: 	(detected by 1, t=10503 jiffies, g=29661, q=179206 ncpus=2)
task:syz-executor    state:R  running task     stack:22784 pid:5851  tgid:5851  ppid:5843   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5369 [inline]
 __schedule+0x1850/0x4c30 kernel/sched/core.c:6756
 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6935
 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6959
 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12
 unwind_next_frame+0x18f8/0x22d0 arch/x86/kernel/unwind_orc.c:672
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122
 save_stack+0xfb/0x1f0 mm/page_owner.c:156
 __reset_page_owner+0x76/0x430 mm/page_owner.c:297
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1127 [inline]
 free_unref_folios+0xf62/0x1a90 mm/page_alloc.c:2704
 folios_put_refs+0x76c/0x860 mm/swap.c:962
 free_pages_and_swap_cache+0x5c8/0x690 mm/swap_state.c:335
 __tlb_batch_free_encoded_pages mm/mmu_gather.c:136 [inline]
 tlb_batch_pages_flush mm/mmu_gather.c:149 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:366 [inline]
 tlb_flush_mmu+0x3a3/0x680 mm/mmu_gather.c:373
 tlb_finish_mmu+0xd4/0x200 mm/mmu_gather.c:465
 exit_mmap+0x496/0xc20 mm/mmap.c:1680
 __mmput+0x115/0x3c0 kernel/fork.c:1353
 exit_mm+0x220/0x310 kernel/exit.c:570
 do_exit+0x9b2/0x28e0 kernel/exit.c:925
 do_group_exit+0x207/0x2c0 kernel/exit.c:1087
 get_signal+0x16b2/0x1750 kernel/signal.c:3016
 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: 0033:0x7fbf3f176a97
RSP: 002b:00007fffc0ea6ec0 EFLAGS: 00000293 ORIG_RAX: 000000000000003d
RAX: fffffffffffffe00 RBX: 00000000000016f3 RCX: 00007fbf3f176a97
RDX: 0000000040000000 RSI: 00007fffc0ea6efc RDI: 00000000ffffffff
RBP: 00007fffc0ea6efc R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000008
R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000
 </TASK>
task:udevd           state:R  running task     stack:24752 pid:6590  tgid:6590  ppid:5225   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5369 [inline]
 __schedule+0x1850/0x4c30 kernel/sched/core.c:6756
 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7078
 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:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5853
Code: 2b 00 74 08 4c 89 f7 e8 da ac 8f 00 f6 44 24 61 02 0f 85 85 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:ffffc90003637580 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff920006c6ebc RCX: ffff88802c9c46d8
RDX: dffffc0000000000 RSI: ffffffff8c0aeb60 RDI: ffffffff8c6158a0
RBP: ffffc900036376c8 R08: ffffffff94321887 R09: 1ffffffff2864310
R10: dffffc0000000000 R11: fffffbfff2864311 R12: 1ffff920006c6eb8
R13: dffffc0000000000 R14: ffffc900036375e0 R15: 0000000000000246
 rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 rcu_read_lock include/linux/rcupdate.h:849 [inline]
 page_ext_get+0x3d/0x2a0 mm/page_ext.c:525
 __reset_page_owner+0x30/0x430 mm/page_owner.c:290
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1127 [inline]
 free_unref_page+0xdef/0x1130 mm/page_alloc.c:2657
 __slab_free+0x31b/0x3d0 mm/slub.c:4509
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
 __kasan_kmalloc+0x23/0xb0 mm/kasan/common.c:385
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __do_kmalloc_node mm/slub.c:4283 [inline]
 __kmalloc_noprof+0x285/0x4c0 mm/slub.c:4295
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1037 [inline]
 tomoyo_encode2 security/tomoyo/realpath.c:45 [inline]
 tomoyo_encode+0x26f/0x540 security/tomoyo/realpath.c:80
 tomoyo_realpath_from_path+0x59e/0x5e0 security/tomoyo/realpath.c:283
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_perm+0x2b7/0x740 security/tomoyo/file.c:822
 tomoyo_path_symlink+0xde/0x120 security/tomoyo/tomoyo.c:212
 security_path_symlink+0x16f/0x370 security/security.c:1979
 do_symlinkat+0x136/0x3a0 fs/namei.c:4693
 __do_sys_symlink fs/namei.c:4716 [inline]
 __se_sys_symlink fs/namei.c:4714 [inline]
 __x64_sys_symlink+0x7a/0x90 fs/namei.c:4714
 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: 0033:0x7f8547d17ce7
RSP: 002b:00007ffc9fdf55b8 EFLAGS: 00000202 ORIG_RAX: 0000000000000058
RAX: ffffffffffffffda RBX: 00007ffc9fdf5658 RCX: 00007f8547d17ce7
RDX: 0000000000000000 RSI: 00007ffc9fdf5f78 RDI: 00007ffc9fdf5658
RBP: 00007ffc9fdf5f78 R08: 0000000000000000 R09: 00007ffc9fdf5838
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000005
R13: 000055cbce02c690 R14: 000055cbce02beb0 R15: 00007ffc9fdf5f89
 </TASK>
rcu: rcu_preempt kthread starved for 10587 jiffies! g29661 f0x2 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:25712 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5369 [inline]
 __schedule+0x1850/0x4c30 kernel/sched/core.c:6756
 __schedule_loop kernel/sched/core.c:6833 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6848
 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045
 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247
 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 UID: 0 PID: 16 Comm: ksoftirqd/0 Not tainted 6.12.0-syzkaller-10740-g509f806f7f70 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:__kasan_check_read+0xa/0x20 mm/kasan/shadow.c:31
Code: db eb d0 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 89 f6 48 8b 0c 24 <31> d2 e9 6f e6 ff ff 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00
RSP: 0018:ffffc90000156ca0 EFLAGS: 00000047
RAX: 0000000000000000 RBX: 0000000000000021 RCX: ffffffff8171939a
RDX: 0000000000000008 RSI: 0000000000000008 RDI: ffffffff94321880
RBP: 0000000000000009 R08: ffffffff94321887 R09: 1ffffffff2864310
R10: dffffc0000000000 R11: fffffbfff2864311 R12: ffff88801d2864c4
R13: dffffc0000000000 R14: 0000000000000200 R15: ffff88801d286530
FS:  0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555804cc5c8 CR3: 000000006380a000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 instrument_atomic_read include/linux/instrumented.h:68 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
 hlock_class kernel/locking/lockdep.c:228 [inline]
 mark_lock+0x9a/0x360 kernel/locking/lockdep.c:4727
 mark_usage kernel/locking/lockdep.c:4670 [inline]
 __lock_acquire+0xc3e/0x2100 kernel/locking/lockdep.c:5180
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
 rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 rcu_read_lock include/linux/rcupdate.h:849 [inline]
 ipv6_get_ifaddr+0x200/0x8f0 net/ipv6/addrconf.c:2091
 ndisc_recv_ns+0x60e/0x1240 net/ipv6/ndisc.c:852
 icmpv6_rcv+0x1128/0x19e0 net/ipv6/icmp.c:987
 ip6_protocol_deliver_rcu+0x105b/0x1580 net/ipv6/ip6_input.c:436
 ip6_input_finish+0x187/0x2d0 net/ipv6/ip6_input.c:481
 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314
 ip6_input net/ipv6/ip6_input.c:490 [inline]
 ip6_mc_input+0x9c5/0xc30 net/ipv6/ip6_input.c:584
 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314
 __netif_receive_skb_one_core net/core/dev.c:5672 [inline]
 __netif_receive_skb+0x1ea/0x650 net/core/dev.c:5785
 process_backlog+0x662/0x15b0 net/core/dev.c:6117
 __napi_poll+0xcb/0x490 net/core/dev.c:6877
 napi_poll net/core/dev.c:6946 [inline]
 net_rx_action+0x89b/0x1240 net/core/dev.c:7068
 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:554
 run_ksoftirqd+0xca/0x130 kernel/softirq.c:943
 smpboot_thread_fn+0x544/0xa30 kernel/smpboot.c:164
 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>
net_ratelimit: 25177 callbacks suppressed
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:da:5b:69:e7:4a:5c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
net_ratelimit: 29021 callbacks suppressed
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:da:5b:69:e7:4a:5c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:da:5b:69:e7:4a:5c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)

Crashes (6):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/11/30 03:49 upstream 509f806f7f70 68914665 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: rcu detected stall in sys_symlink
2024/10/30 22:41 upstream 4236f913808c fb888278 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: rcu detected stall in sys_symlink
2024/10/11 01:52 upstream d3d1556696c1 8fbfc0c8 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: rcu detected stall in sys_symlink
2024/08/09 20:39 upstream ee9a43b7cfe2 a9e7e9e3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in sys_symlink
2024/07/05 16:09 upstream 661e504db04c 2a40360c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in sys_symlink
2024/10/06 09:07 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 4a9fe2a8ac53 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb INFO: rcu detected stall in sys_symlink
* Struck through repros no longer work on HEAD.