rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P10026/1:b..l P6652/1:b..l P5036/1:b..l (detected by 1, t=10503 jiffies, g=53381, q=43 ncpus=2) task:kworker/u4:21 state:R running task stack:22688 pid:5036 ppid:2 flags:0x00004000 Workqueue: bat_events batadv_nc_worker Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10e9/0x40d0 kernel/sched/core.c:6561 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873 irqentry_exit+0x63/0x70 kernel/entry/common.c:439 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:lock_acquire+0x20f/0x490 kernel/locking/lockdep.c:5666 Code: 00 9c 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 0f 85 f5 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 44 3d 00 00 00 00 00 66 43 c7 44 3d 09 00 00 43 c6 44 3d 0b RSP: 0018:ffffc90004bafac0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 0000000000000000 RCX: ac0e9bdec6fae500 RDX: 0000000000000000 RSI: ffffffff8a6c1180 RDI: ffffffff8abf1260 RBP: ffffc90004bafbc8 R08: dffffc0000000000 R09: fffffbfff2117049 R10: fffffbfff2117049 R11: 1ffffffff2117048 R12: 0000000000000001 R13: 1ffff92000975f64 R14: 0000000000000246 R15: dffffc0000000000 rcu_lock_acquire include/linux/rcupdate.h:350 [inline] rcu_read_lock include/linux/rcupdate.h:791 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0xeb/0x600 net/batman-adv/network-coding.c:719 process_one_work+0x898/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 task:udevd state:R running task stack:23584 pid:6652 ppid:3623 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10e9/0x40d0 kernel/sched/core.c:6561 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873 irqentry_exit+0x63/0x70 kernel/entry/common.c:439 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:mas_validate_limits lib/maple_tree.c:7141 [inline] RIP: 0010:mt_validate+0x1c7d/0x4c90 lib/maple_tree.c:7239 Code: f7 4c 8b b4 24 40 01 00 00 4c 89 ff 4c 89 f6 e8 79 f4 83 f7 4d 39 f7 0f 82 1f 01 00 00 e8 8b f2 83 f7 4c 8b b4 24 48 01 00 00 <4c> 89 ff 4c 89 f6 e8 58 f4 83 f7 4d 39 f7 0f 87 7a 01 00 00 e8 6a RSP: 0018:ffffc90003c77720 EFLAGS: 00000293 RAX: ffffffff89fce485 RBX: 000000000000000a RCX: ffff88807b559dc0 RDX: 0000000000000000 RSI: 00007f3b957f1000 RDI: 00007f3b95886fff RBP: ffffc90003c778f0 R08: ffff88807b559dc0 R09: 0000000000000003 R10: 0000000000000003 R11: 0000000000000000 R12: dffffc0000000000 R13: ffff888064d4b280 R14: 00007f3b95887fff R15: 00007f3b95886fff validate_mm_mt+0xcd/0x420 mm/mmap.c:294 validate_mm+0xcc/0x2b0 mm/mmap.c:331 do_mas_align_munmap+0xfad/0x1220 mm/mmap.c:2587 do_mas_munmap+0x240/0x2b0 mm/mmap.c:2638 __vm_munmap+0x18d/0x290 mm/mmap.c:2924 __do_sys_munmap mm/mmap.c:2949 [inline] __se_sys_munmap mm/mmap.c:2946 [inline] __x64_sys_munmap+0x5c/0x70 mm/mmap.c:2946 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f3b9511e097 RSP: 002b:00007ffcc29f22e8 EFLAGS: 00000246 ORIG_RAX: 000000000000000b RAX: ffffffffffffffda RBX: 000055bd6d4c92e0 RCX: 00007f3b9511e097 RDX: 000055bd6d4c54e8 RSI: 0000000000000200 RDI: 00007f3b95763000 RBP: 0000000000000012 R08: 000055bd6d4c92b0 R09: 0000000000000003 R10: 0000000000000040 R11: 0000000000000246 R12: 000055bd6d4c8ce0 R13: 00007f3b9584f39c R14: 0000000000002400 R15: 0000000000000009 task:syz.0.1278 state:R running task stack:23584 pid:10026 ppid:4251 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10e9/0x40d0 kernel/sched/core.c:6561 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873 irqentry_exit+0x63/0x70 kernel/entry/common.c:439 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:xas_load+0x6c/0x140 lib/xarray.c:-1 Code: 89 dc 41 83 e4 03 bf 02 00 00 00 4c 89 e6 e8 fb ea 7e f7 48 81 fb 01 10 00 00 0f 82 b2 00 00 00 41 83 fc 02 0f 85 a8 00 00 00 <48> 8b 44 24 10 42 0f b6 04 30 84 c0 75 5c 4c 8d 7b fe 48 8b 04 24 RSP: 0018:ffffc90003d177d0 EFLAGS: 00000246 RAX: ffffffff8a01eff5 RBX: ffff88807a853c82 RCX: ffff88807a051dc0 RDX: 0000000000000002 RSI: 0000000000000002 RDI: 0000000000000002 RBP: ffffc90003d17940 R08: dffffc0000000000 R09: fffffbfff2117049 R10: fffffbfff2117049 R11: 1ffffffff2117048 R12: 0000000000000002 R13: dffffc0000000000 R14: dffffc0000000000 R15: ffffc90003d17880 mapping_get_entry mm/filemap.c:1881 [inline] __filemap_get_folio+0x1bb/0xdd0 mm/filemap.c:1943 shmem_get_folio_gfp+0x310/0x3400 mm/shmem.c:1881 shmem_get_folio mm/shmem.c:2072 [inline] shmem_write_begin+0xee/0x3f0 mm/shmem.c:2556 generic_perform_write+0x2db/0x560 mm/filemap.c:3846 __generic_file_write_iter+0x172/0x430 mm/filemap.c:3974 generic_file_write_iter+0xab/0x2e0 mm/filemap.c:4006 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x44c/0x960 fs/read_write.c:584 ksys_write+0x143/0x240 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fa3eb38d41f RSP: 002b:00007fa3ec173df0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007fa3eb38d41f RDX: 0000000001000000 RSI: 00007fa3e0bf7000 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000009600 R10: 0000200000009682 R11: 0000000000000293 R12: 0000000000000003 R13: 00007fa3ec173ef0 R14: 00007fa3ec173eb0 R15: 00007fa3e0bf7000 rcu: rcu_preempt kthread starved for 10603 jiffies! g53381 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:27840 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10e9/0x40d0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1965 rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706 rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 PID: 10037 Comm: syz.5.1280 Not tainted 6.1.140-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline] RIP: 0010:static_key_false include/linux/jump_label.h:207 [inline] RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:147 [inline] RIP: 0010:wrmsr arch/x86/include/asm/msr.h:254 [inline] RIP: 0010:native_apic_msr_write+0x35/0x50 arch/x86/include/asm/apic.h:206 Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 c3 89 f6 31 d2 e9 df 65 f8 02 66 2e 0f 1f 84 00 00 00 00 00 RSP: 0018:ffffc9000457fcb0 EFLAGS: 00000246 RAX: 00000000000000f6 RBX: ffffffff8c3d0b78 RCX: 000000000000083f RDX: 0000000000000000 RSI: 00000000000000f6 RDI: 000000000000083f RBP: 0000000000000000 R08: dffffc0000000000 R09: fffff520008aff85 R10: fffff520008aff85 R11: 1ffff920008aff84 R12: ffff8880b8f33e01 R13: dffffc0000000000 R14: dffffc0000000000 R15: 0000000000000020 FS: 00007f6b4e83d6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055e3bd40a078 CR3: 0000000075732000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_irq_work_raise+0x82/0xd0 arch/x86/kernel/irq_work.c:31 irq_work_queue+0x95/0x140 kernel/irq_work.c:114 bpf_send_signal_common+0x2b2/0x420 kernel/trace/bpf_trace.c:879 ____bpf_send_signal kernel/trace/bpf_trace.c:888 [inline] bpf_send_signal+0x15/0x20 kernel/trace/bpf_trace.c:886 bpf_prog_7ba5217f62dcd359+0x38/0x3c bpf_dispatcher_nop_func include/linux/bpf.h:1001 [inline] __bpf_prog_run include/linux/filter.h:603 [inline] bpf_prog_run include/linux/filter.h:610 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2285 [inline] bpf_trace_run2+0x1cd/0x3b0 kernel/trace/bpf_trace.c:2324 __bpf_trace_sys_enter+0x60/0x70 include/trace/events/syscalls.h:18 trace_sys_enter+0x6b/0x80 include/trace/events/syscalls.h:18 syscall_trace_enter+0xf0/0x150 kernel/entry/common.c:81 do_syscall_64+0x24/0xa0 arch/x86/entry/common.c:77 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f6b4d98e969 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:00007f6b4e83d0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00007f6b4dbb5fa8 RCX: 00007f6b4d98e969 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f6b4dbb5fa8 RBP: 00007f6b4dbb5fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f6b4dbb5fac R13: 0000000000000000 R14: 00007ffcfd98d230 R15: 00007ffcfd98d318