rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6413/1:b..l P6475/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=15397, q=1081 ncpus=2)
task:rm state:R running task stack:24104 pid:6475 tgid:6475 ppid:6443 task_flags:0x400000 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6785
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7108
irqentry_exit+0x6f/0x90 kernel/entry/common.c:307
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:246 [inline]
RIP: 0010:__sanitizer_cov_trace_switch+0x9e/0x130 kernel/kcov.c:351
Code: 65 4c 8b 04 25 08 00 9d 92 45 31 c9 eb 08 49 ff c1 4c 39 c8 74 77 4e 8b 54 ce 10 65 44 8b 1d a9 ab dc 10 41 81 e3 00 01 ff 00 <74> 13 41 81 fb 00 01 00 00 75 d9 41 83 b8 3c 16 00 00 00 74 cf 45
RSP: 0018:ffffc9000b79f840 EFLAGS: 00000246
RAX: 0000000000000002 RBX: 0000000000000081 RCX: 0000000000000003
RDX: ffffffff82374a59 RSI: ffffffff8e28b980 RDI: 0000000000004000
RBP: 0000000000000000 R08: ffff88802c5e8000 R09: 0000000000000001
R10: 0000000000006000 R11: 0000000000000000 R12: 1ffff110291992b7
R13: 0000000000000000 R14: ffff888148cc95b8 R15: 0000000000004000
devcgroup_inode_permission include/linux/device_cgroup.h:21 [inline]
inode_permission+0xe9/0x470 fs/namei.c:597
may_lookup fs/namei.c:1845 [inline]
link_path_walk+0x232/0xea0 fs/namei.c:2454
path_openat+0x28c/0x3830 fs/namei.c:4051
do_filp_open+0x1fa/0x410 fs/namei.c:4082
do_sys_openat2+0x121/0x1c0 fs/open.c:1437
do_sys_open fs/open.c:1452 [inline]
__do_sys_openat fs/open.c:1468 [inline]
__se_sys_openat fs/open.c:1463 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1463
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1a7d3a90ba
RSP: 002b:00007fff74f34fd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fff74f35050 RCX: 00007f1a7d3a90ba
RDX: 0000000000080000 RSI: 00007fff74f35050 RDI: 00000000ffffff9c
RBP: 00007fff74f35040 R08: 00007fff74f35247 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000032
R13: 00007f1a7d37d050 R14: 00007fff74f35260 R15: 0000000000000000
task:syz-executor state:R running task stack:22760 pid:6413 tgid:6413 ppid:6395 task_flags:0x400140 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6785
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7108
irqentry_exit+0x6f/0x90 kernel/entry/common.c:307
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:rcu_lock_release include/linux/rcupdate.h:341 [inline]
RIP: 0010:rcu_read_unlock include/linux/rcupdate.h:871 [inline]
RIP: 0010:class_rcu_destructor include/linux/rcupdate.h:1155 [inline]
RIP: 0010:unwind_next_frame+0x19a1/0x2390 arch/x86/kernel/unwind_orc.c:680
Code: 0e 00 75 1f c6 05 eb 2c 18 0e 01 48 c7 c7 a0 3c 88 8b be 66 03 00 00 48 c7 c2 40 3d 88 8b e8 c6 a8 2b 00 48 c7 c7 60 ee 13 8e <4c> 89 fe e8 a7 8e 2b 00 e8 22 25 35 00 89 d8 48 81 c4 98 00 00 00
RSP: 0018:ffffc9000b6ce978 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffffff90c35601 RCX: a93f41ded4eecd00
RDX: ffffc9000b6cea01 RSI: ffffffff8be28d20 RDI: ffffffff8e13ee60
RBP: dffffc0000000000 R08: ffffc9000b6cf190 R09: ffffc9000b6cea98
R10: dffffc0000000000 R11: fffff520016d9d55 R12: ffffc9000b6cf1a0
R13: ffffc9000b6c8000 R14: ffffc9000b6cea48 R15: ffffffff81728af5
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394
kasan_kmalloc include/linux/kasan.h:260 [inline]
__kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4359
kmalloc_noprof include/linux/slab.h:905 [inline]
kzalloc_noprof include/linux/slab.h:1039 [inline]
kobject_create lib/kobject.c:768 [inline]
kobject_create_and_add+0x5b/0x240 lib/kobject.c:794
br_sysfs_addbr+0x6a/0x160 net/bridge/br_sysfs_br.c:1063
br_device_event+0x1c8/0x910 net/bridge/br.c:46
notifier_call_chain+0x1b6/0x3e0 kernel/notifier.c:85
call_netdevice_notifiers_extack net/core/dev.c:2268 [inline]
call_netdevice_notifiers net/core/dev.c:2282 [inline]
register_netdevice+0x1608/0x1ae0 net/core/dev.c:11143
br_dev_newlink+0x6a/0x140 net/bridge/br_netlink.c:1565
rtnl_newlink_create+0x310/0xb00 net/core/rtnetlink.c:3823
__rtnl_newlink net/core/rtnetlink.c:3940 [inline]
rtnl_newlink+0x16d6/0x1c70 net/core/rtnetlink.c:4055
rtnetlink_rcv_msg+0x7cf/0xb70 net/core/rtnetlink.c:6944
netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2534
netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
netlink_unicast+0x75b/0x8d0 net/netlink/af_netlink.c:1339
netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1883
sock_sendmsg_nosec net/socket.c:712 [inline]
__sock_sendmsg+0x21c/0x270 net/socket.c:727
__sys_sendto+0x3bd/0x520 net/socket.c:2180
__do_sys_sendto net/socket.c:2187 [inline]
__se_sys_sendto net/socket.c:2183 [inline]
__x64_sys_sendto+0xde/0x100 net/socket.c:2183
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f11b85907bc
RSP: 002b:00007ffd3e7ff730 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f11b92e4620 RCX: 00007f11b85907bc
RDX: 000000000000003c RSI: 00007f11b92e4670 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007ffd3e7ff784 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f11b92e4670 R15: 0000000000000000
rcu: rcu_preempt kthread starved for 10496 jiffies! g15397 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:27320 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6785
__schedule_loop kernel/sched/core.c:6863 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6878
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256
kthread+0x711/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 6477 Comm: syz.4.77 Not tainted 6.16.0-rc3-syzkaller-00306-gaaf724ed6926 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0xf6e/0x12d0 kernel/smp.c:885
Code: 89 ee 83 e6 01 31 ff e8 c0 79 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 6b 75 0b 00 eb 37 f3 90 43 0f b6 04 2c <84> c0 75 10 41 f7 07 01 00 00 00 74 1e e8 50 75 0b 00 eb e5 44 89
RSP: 0000:ffffc900053a7720 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff8880b873b1c0 RCX: 0000000000080000
RDX: ffffc9000f129000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc900053a7880 R08: ffffffff8fa104f7 R09: 1ffffffff1f4209e
R10: dffffc0000000000 R11: fffffbfff1f4209f R12: 1ffff110170c8385
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8880b8641c28
FS: 00007f2e404536c0(0000) GS:ffff888125d50000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2e34e024e2 CR3: 000000004b9e0000 CR4: 0000000000350ef0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052
__flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
flush_tlb_mm_range+0x6b1/0x12c0 arch/x86/mm/tlb.c:1451
flush_tlb_page arch/x86/include/asm/tlbflush.h:324 [inline]
ptep_clear_flush+0x120/0x170 mm/pgtable-generic.c:101
wp_page_copy mm/memory.c:3635 [inline]
do_wp_page+0x1bc2/0x5800 mm/memory.c:4030
handle_pte_fault mm/memory.c:6085 [inline]
__handle_mm_fault+0x1144/0x5620 mm/memory.c:6212
handle_mm_fault+0x40a/0x8e0 mm/memory.c:6381
do_user_addr_fault+0xa81/0x1390 arch/x86/mm/fault.c:1336
handle_page_fault arch/x86/mm/fault.c:1476 [inline]
exc_page_fault+0x76/0xf0 arch/x86/mm/fault.c:1532
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x7f2e3f450ca3
Code: 1f 84 00 00 00 00 00 3d 00 01 00 00 75 29 45 31 f6 48 83 c4 18 44 89 f0 5b 5d 41 5c 41 5d 41 5e 41 5f c3 0f 1f 40 00 49 8b 0f <44> 88 34 01 49 83 47 10 01 eb 92 66 90 8d 90 ff fe ff ff 83 fa 1c
RSP: 002b:00007f2e404524a0 EFLAGS: 00010202
RAX: 00000000000024e2 RBX: 00007f2e40452540 RCX: 00007f2e34e00000
RDX: 00007f2e404526e0 RSI: 0000000000000001 RDI: 00007f2e404525e0
RBP: 0000000000000027 R08: 0000000000000006 R09: 0000000000000003
R10: 0000000000000018 R11: 00007f2e40452540 R12: 0000000000000001
R13: 00007f2e3f62c200 R14: 0000000000000026 R15: 00007f2e404525e0