rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P9157/1:b..l P25098/3:b..l rcu: (detected by 1, t=10502 jiffies, g=174185, q=189 ncpus=2) task:syz.1.6879 state:R running task stack:26240 pid:25098 tgid:25095 ppid:24166 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0xe37/0x5490 kernel/sched/core.c:6529 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:6851 irqentry_exit+0x36/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x1f2/0x560 kernel/locking/lockdep.c:5727 Code: c1 05 4a 11 9a 7e 83 f8 01 0f 85 ea 02 00 00 9c 58 f6 c4 02 0f 85 d5 02 00 00 48 85 ed 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24 RSP: 0018:ffffc9000374f668 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff920006e9ecf RCX: 0000000000000001 RDX: 0000000000000001 RSI: ffffffff8b4cc800 RDI: ffffffff8bb08ec0 RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff28c5ad8 R10: ffffffff9462d6c7 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff8ddb5ce0 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:326 [inline] rcu_read_lock include/linux/rcupdate.h:838 [inline] page_ref_add_unless.constprop.0+0x36/0x390 include/linux/page_ref.h:235 folio_ref_add_unless include/linux/page_ref.h:248 [inline] folio_try_get include/linux/page_ref.h:264 [inline] next_uptodate_folio+0xf6/0x4b0 mm/filemap.c:3476 filemap_map_pages+0x1c5/0x1440 mm/filemap.c:3616 do_fault_around mm/memory.c:5019 [inline] do_read_fault mm/memory.c:5052 [inline] do_fault mm/memory.c:5191 [inline] do_pte_missing mm/memory.c:3947 [inline] handle_pte_fault mm/memory.c:5522 [inline] __handle_mm_fault+0x36da/0x5660 mm/memory.c:5665 handle_mm_fault+0x44e/0x7b0 mm/memory.c:5833 faultin_page mm/gup.c:1194 [inline] __get_user_pages+0x475/0x15c0 mm/gup.c:1493 populate_vma_page_range+0x27f/0x3a0 mm/gup.c:1932 __mm_populate+0x1d6/0x380 mm/gup.c:2035 mm_populate include/linux/mm.h:3415 [inline] vm_mmap_pgoff+0x293/0x360 mm/util.c:593 ksys_mmap_pgoff+0x7d/0x5d0 mm/mmap.c:1514 __do_sys_mmap arch/x86/kernel/sys_x86_64.c:86 [inline] __se_sys_mmap arch/x86/kernel/sys_x86_64.c:79 [inline] __x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:79 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0f14d799f9 RSP: 002b:00007f0f15bb2038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f0f14f15f80 RCX: 00007f0f14d799f9 RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000000020000000 RBP: 00007f0f14de78ee R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f0f14f15f80 R15: 00007fffdf167258 task:kworker/u8:18 state:R running task stack:23440 pid:9157 tgid:9157 ppid:2 flags:0x00004000 Workqueue: bat_events batadv_nc_worker Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0xe37/0x5490 kernel/sched/core.c:6529 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:6851 irqentry_exit+0x36/0x90 kernel/entry/common.c:354 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0010:debug_lockdep_rcu_enabled+0x14/0x40 kernel/rcu/update.c:320 Code: 00 00 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 8b 05 4a d5 00 05 85 c0 74 20 8b 05 44 05 01 05 <85> c0 74 16 65 48 8b 05 40 d1 f1 74 8b 80 dc 0a 00 00 85 c0 0f 94 RSP: 0018:ffffc9000366fb88 EFLAGS: 00000202 RAX: 0000000000000001 RBX: ffff88805344c968 RCX: ffffffff8ad68db9 RDX: ffff888024f7bc00 RSI: ffffffff8ad689db RDI: 0000000000000001 RBP: 000000000000012d R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffff888075ebd340 R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000001 rcu_read_unlock include/linux/rcupdate.h:867 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline] batadv_nc_worker+0x8c0/0x10f0 net/batman-adv/network-coding.c:719 process_one_work+0x9c5/0x1b40 kernel/workqueue.c:3231 process_scheduled_works kernel/workqueue.c:3312 [inline] worker_thread+0x6c8/0xf20 kernel/workqueue.c:3390 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: rcu_preempt kthread starved for 10558 jiffies! g174185 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:27680 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0xe37/0x5490 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6621 schedule_timeout+0x136/0x2a0 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2034 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2236 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 6.11.0-rc3-syzkaller-00013-g6b0f8db921ab #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline] RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:92 [inline] RIP: 0010:acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:112 Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 65 48 8b 05 18 a7 f1 74 48 8b 00 a8 08 75 0c 66 90 0f 00 2d c8 c3 a9 00 fb f4 c3 cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc900001a7d58 EFLAGS: 00000246 RAX: 0000000000004000 RBX: 0000000000000001 RCX: ffffffff8b121709 RDX: 0000000000000001 RSI: ffff88801a2cc800 RDI: ffff88801a2cc864 RBP: ffff88801a2cc864 R08: 0000000000000001 R09: ffffed1017266fd9 R10: ffff8880b9337ecb R11: 0000000000000000 R12: ffff88801a74c800 R13: ffffffff8e951c20 R14: 0000000000000001 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000002006b000 CR3: 000000007e758000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: acpi_idle_enter+0xc5/0x160 drivers/acpi/processor_idle.c:702 cpuidle_enter_state+0x85/0x500 drivers/cpuidle/cpuidle.c:267 cpuidle_enter+0x4e/0xa0 drivers/cpuidle/cpuidle.c:388 cpuidle_idle_call kernel/sched/idle.c:230 [inline] do_idle+0x313/0x3f0 kernel/sched/idle.c:326 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:424 start_secondary+0x220/0x2b0 arch/x86/kernel/smpboot.c:313 common_startup_64+0x13e/0x148