rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P59/1:b..l P7459/1:b..l P5813/1:b..l rcu: (detected by 0, t=10502 jiffies, g=16329, q=326 ncpus=2) task:syz-executor state:R running task stack:23544 pid:5813 tgid:5813 ppid:5809 task_flags:0x400140 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x116a/0x5de0 kernel/sched/core.c:6785 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6965 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] copy_pte_range mm/memory.c:1206 [inline] copy_pmd_range mm/memory.c:1267 [inline] copy_pud_range mm/memory.c:1304 [inline] copy_p4d_range mm/memory.c:1328 [inline] copy_page_range+0x13c5/0x5740 mm/memory.c:1416 dup_mmap+0xe88/0x21d0 mm/mmap.c:1838 dup_mm kernel/fork.c:1477 [inline] copy_mm kernel/fork.c:1529 [inline] copy_process+0x4081/0x76a0 kernel/fork.c:2169 kernel_clone+0xfc/0x960 kernel/fork.c:2599 __do_sys_clone+0xce/0x120 kernel/fork.c:2742 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6113785193 RSP: 002b:00007ffcd1060918 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f6113785193 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001 R10: 00005555634df7d0 R11: 0000000000000246 R12: 0000000000000000 R13: 00000000000927c0 R14: 000000000002d02b R15: 00007ffcd1060ab0 task:modprobe state:R running task stack:25352 pid:7459 tgid:7459 ppid:5956 task_flags:0x400000 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x116a/0x5de0 kernel/sched/core.c:6785 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7108 irqentry_exit+0x36/0x90 kernel/entry/common.c:307 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline] RIP: 0010:write_comp_data+0x11/0x90 kernel/kcov.c:246 Code: c6 09 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 49 89 d2 49 89 f8 49 89 f1 65 48 8b 15 d7 a9 10 12 <65> 8b 05 e8 a9 10 12 a9 00 01 ff 00 74 1d f6 c4 01 74 67 a9 00 00 RSP: 0018:ffffc90005ac78c0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 00007f2f72b00000 RCX: ffffffff820e8a66 RDX: ffff88802eeca440 RSI: 0000000000000000 RDI: 0000000000000007 RBP: 000000005b7fb067 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 000000005b7fb007 R13: ffff888035844ca8 R14: ffffc90005ac7b40 R15: 0000000000000000 pmd_pfn_mask arch/x86/include/asm/pgtable_types.h:459 [inline] pmd_flags_mask arch/x86/include/asm/pgtable_types.h:467 [inline] pmd_flags arch/x86/include/asm/pgtable_types.h:472 [inline] pmd_present arch/x86/include/asm/pgtable.h:1039 [inline] is_swap_pmd include/linux/huge_mm.h:446 [inline] is_pmd_migration_entry include/linux/swapops.h:564 [inline] ___pte_offset_map+0xe6/0x570 mm/pgtable-generic.c:294 __pte_offset_map include/linux/mm.h:2995 [inline] __pte_offset_map_lock+0x8d/0x310 mm/pgtable-generic.c:398 pte_offset_map_lock include/linux/mm.h:3010 [inline] change_pte_range mm/mprotect.c:99 [inline] change_pmd_range mm/mprotect.c:409 [inline] change_pud_range mm/mprotect.c:472 [inline] change_p4d_range mm/mprotect.c:498 [inline] change_protection_range mm/mprotect.c:526 [inline] change_protection+0x11db/0x3550 mm/mprotect.c:560 mprotect_fixup+0x559/0xb10 mm/mprotect.c:676 do_mprotect_pkey+0x9ca/0xd50 mm/mprotect.c:832 __do_sys_mprotect mm/mprotect.c:853 [inline] __se_sys_mprotect mm/mprotect.c:850 [inline] __x64_sys_mprotect+0x78/0xc0 mm/mprotect.c:850 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2f72dd02c7 RSP: 002b:00007ffe93cbab18 EFLAGS: 00000206 ORIG_RAX: 000000000000000a RAX: ffffffffffffffda RBX: 00007f2f72da4b20 RCX: 00007f2f72dd02c7 RDX: 0000000000000001 RSI: 0000000000001000 RDI: 00007f2f72b00000 RBP: 00007ffe93cbade0 R08: 0000000000000000 R09: 00007f2f72b3a2e0 R10: 00007f2f72da4b20 R11: 0000000000000206 R12: 0000000000000018 R13: 0000007b30c1f6a9 R14: 0000000000000000 R15: 00007f2f72de4310 task:kworker/u8:4 state:R running task stack:23384 pid:59 tgid:59 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: bat_events batadv_nc_worker Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x116a/0x5de0 kernel/sched/core.c:6785 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7108 irqentry_exit+0x36/0x90 kernel/entry/common.c:307 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x62/0x350 kernel/locking/lockdep.c:5875 Code: 42 34 12 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 42 91 0f 0f 0f 82 74 02 00 00 8b 35 2a c3 0f 0f 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 d9 41 34 12 0f 85 c7 02 00 00 48 83 c4 RSP: 0018:ffffc9000210fab0 EFLAGS: 00000206 RAX: 0000000000000046 RBX: ffffffff8e5c4840 RCX: 0000000095aa05c5 RDX: 0000000000000000 RSI: ffffffff8ddf4151 RDI: ffffffff8c1570a0 RBP: 0000000000000002 R08: 9500627d63e3edae R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0x16a/0x1030 net/batman-adv/network-coding.c:719 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3321 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402 kthread+0x3c5/0x780 kernel/kthread.c:464 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: rcu_preempt kthread starved for 10445 jiffies! g16329 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:27784 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x116a/0x5de0 kernel/sched/core.c:6785 __schedule_loop kernel/sched/core.c:6863 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6878 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2054 rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2256 kthread+0x3c5/0x780 kernel/kthread.c:464 ret_from_fork+0x5d4/0x6f0 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: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 6.16.0-rc1-syzkaller-00101-g27605c8c0f69 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82 Code: 9b 72 02 e9 03 fb 02 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 23 20 2a 00 fb f4 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffc90000197df8 EFLAGS: 000002c6 RAX: 0000000000701f7d RBX: 0000000000000001 RCX: ffffffff8b7fec99 RDX: 0000000000000000 RSI: ffffffff8de19624 RDI: ffffffff8c1570a0 RBP: ffffed1003c5a488 R08: 0000000000000001 R09: ffffed10170a6645 R10: ffff8880b853322b R11: 0000000000000001 R12: 0000000000000001 R13: ffff88801e2d2440 R14: ffffffff90a80f50 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888124854000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f404ad4984d CR3: 0000000076665000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:749 default_idle_call+0x6d/0xb0 kernel/sched/idle.c:117 cpuidle_idle_call kernel/sched/idle.c:185 [inline] do_idle+0x391/0x510 kernel/sched/idle.c:325 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:423 start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:315 common_startup_64+0x13e/0x148