rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P24545/1:b..l P13303/1:b..l rcu: (detected by 1, t=10502 jiffies, g=91833, q=371 ncpus=2) task:syz-executor.4 state:R running task stack:20016 pid:13303 tgid:13303 ppid:13265 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5409 [inline] __schedule+0x17e8/0x4a50 kernel/sched/core.c:6746 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7068 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:check_kcov_mode kernel/kcov.c:184 [inline] RIP: 0010:write_comp_data kernel/kcov.c:236 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x35/0x90 kernel/kcov.c:304 Code: 14 25 80 d3 03 00 65 8b 05 00 9f 6d 7e a9 00 01 ff 00 74 10 a9 00 01 00 00 74 5b 83 ba 1c 16 00 00 00 74 52 8b 82 f8 15 00 00 <83> f8 03 75 47 48 8b 8a 00 16 00 00 44 8b 8a fc 15 00 00 49 c1 e1 RSP: 0018:ffffc9000433fec8 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffff8880547a8000 RDX: ffff8880547a8000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000001 R08: ffffffff81621cb3 R09: 1ffffffff25f3ab0 R10: dffffc0000000000 R11: fffffbfff25f3ab1 R12: ffff888063d23dc0 R13: dffffc0000000000 R14: ffffffff816219d8 R15: ffff8880628cf110 rcu_read_unlock include/linux/rcupdate.h:810 [inline] __task_pid_nr_ns+0x303/0x450 kernel/pid.c:514 task_tgid_vnr include/linux/pid.h:294 [inline] __do_sys_getpid+0x1e/0x30 kernel/sys.c:960 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9a1bc7a667 RSP: 002b:00007ffd94f8f388 EFLAGS: 00000206 ORIG_RAX: 0000000000000027 RAX: ffffffffffffffda RBX: 00007ffd94f8f4f0 RCX: 00007f9a1bc7a667 RDX: 00007ffd94f8f3c0 RSI: 00007ffd94f8f4f0 RDI: 0000000000000021 RBP: 0000000000000000 R08: 0000000000000000 R09: 7fffffffffffffff R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000032 R13: 00000000000ab6a5 R14: 00000000000ab66d R15: 0000000000000004 task:syz-executor.3 state:R running task stack:25232 pid:24545 tgid:24544 ppid:22876 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5409 [inline] __schedule+0x17e8/0x4a50 kernel/sched/core.c:6746 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7068 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0010:lock_release+0x51/0x9f0 kernel/locking/lockdep.c:5762 Code: 04 25 28 00 00 00 48 89 84 24 e0 00 00 00 49 bf 00 00 00 00 00 fc ff df 48 c7 44 24 60 b3 8a b5 41 48 c7 44 24 68 96 ca b5 8d <48> c7 44 24 70 f0 9c 72 81 4c 8d 64 24 60 49 c1 ec 03 48 b8 f1 f1 RSP: 0018:ffffc9000a40f4e0 EFLAGS: 00000282 RAX: e2e4c4ebe3899f00 RBX: 0000000000000001 RCX: 0000000000040000 RDX: ffffc90019c01000 RSI: ffffffff849a086d RDI: ffffffff8e334360 RBP: ffffc9000a40f608 R08: ffffffff849a09e0 R09: 1ffff1100415b94a R10: dffffc0000000000 R11: ffffed100415b94b R12: 0000000000000a10 R13: ffffffff849a086d R14: ffffffff849a086d R15: dffffc0000000000 rcu_lock_release include/linux/rcupdate.h:339 [inline] rcu_read_unlock include/linux/rcupdate.h:812 [inline] blk_cgroup_congested+0x209/0x220 block/blk-cgroup.c:2156 __folio_throttle_swaprate+0x71/0x1b0 mm/swapfile.c:3662 folio_throttle_swaprate include/linux/swap.h:625 [inline] shmem_add_to_page_cache+0x89c/0x1830 mm/shmem.c:778 shmem_alloc_and_add_folio+0x51f/0xbc0 mm/shmem.c:1689 shmem_get_folio_gfp+0x82d/0x1f50 mm/shmem.c:2055 shmem_get_folio mm/shmem.c:2160 [inline] shmem_write_begin+0x170/0x4d0 mm/shmem.c:2744 generic_perform_write+0x324/0x640 mm/filemap.c:3974 shmem_file_write_iter+0xfc/0x120 mm/shmem.c:2920 call_write_iter include/linux/fs.h:2120 [inline] new_sync_write fs/read_write.c:497 [inline] vfs_write+0xa2f/0xc50 fs/read_write.c:590 ksys_write+0x1a0/0x2c0 fs/read_write.c:643 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd34a67bc2f RSP: 002b:00007fd34b33fe80 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007fd34a67bc2f RDX: 0000000001000000 RSI: 00007fd340400000 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000005598 R10: 0000000000000002 R11: 0000000000000293 R12: 0000000000000003 R13: 00007fd34b33ff80 R14: 00007fd34b33ff40 R15: 00007fd340400000 rcu: rcu_preempt kthread starved for 10578 jiffies! g91833 f0x0 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:24944 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5409 [inline] __schedule+0x17e8/0x4a50 kernel/sched/core.c:6746 __schedule_loop kernel/sched/core.c:6823 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6838 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2582 rcu_gp_fqs_loop+0x2df/0x1370 kernel/rcu/tree.c:2000 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2202 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/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: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 15238 Comm: kworker/0:2H Not tainted 6.9.0-syzkaller-08284-gea5f6ad9ad96 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Workqueue: 0x0 (kblockd) RIP: 0010:rcu_read_lock_sched_held+0x0/0x130 kernel/rcu/update.c:121 Code: 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa e9 77 83 26 00 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 55 48 89 e5 41 57 41 56 41 54 53 48 83 e4 e0 48 83 ec RSP: 0018:ffffc900000079b8 EFLAGS: 00000002 RAX: 0000000000000001 RBX: ffff888024414800 RCX: ffff888063ea3c00 RDX: 0000000080010005 RSI: 0000000000000000 RDI: ffff888066fe3c00 RBP: 000000bc4078ce29 R08: ffffffff813559f1 R09: ffff888066fe3c14 R10: dffffc0000000000 R11: fffffbfff1f59b46 R12: 0000000000000000 R13: dffffc0000000000 R14: ffffffff8e1fb160 R15: ffff888066fe3c00 FS: 0000000000000000(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7403777f80 CR3: 0000000044d60000 CR4: 0000000000350ef0 Call Trace: task_css_set include/linux/cgroup.h:421 [inline] task_dfl_cgroup include/linux/cgroup.h:490 [inline] task_psi_group+0x50/0x1a0 kernel/sched/psi.c:877 psi_task_change+0xd6/0x280 kernel/sched/psi.c:910 psi_enqueue kernel/sched/stats.h:139 [inline] enqueue_task+0x2a6/0x2f0 kernel/sched/core.c:2112 activate_task kernel/sched/core.c:2146 [inline] ttwu_do_activate+0x1d1/0x7e0 kernel/sched/core.c:3793 ttwu_queue kernel/sched/core.c:4057 [inline] try_to_wake_up+0x88b/0x1470 kernel/sched/core.c:4378 signal_wake_up_state+0xb4/0x120 kernel/signal.c:773 signal_wake_up include/linux/sched/signal.h:448 [inline] complete_signal+0x94a/0xcf0 kernel/signal.c:1065 __send_signal_locked+0xb1b/0xdc0 kernel/signal.c:1185 do_send_sig_info kernel/signal.c:1301 [inline] group_send_sig_info+0x292/0x310 kernel/signal.c:1453 do_bpf_send_signal+0x85/0x190 kernel/trace/bpf_trace.c:838 irq_work_single+0xe4/0x240 kernel/irq_work.c:221 irq_work_run_list kernel/irq_work.c:252 [inline] irq_work_run+0x18b/0x350 kernel/irq_work.c:261 __sysvec_irq_work+0xb8/0x430 arch/x86/kernel/irq_work.c:22 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline] sysvec_irq_work+0x9e/0xc0 arch/x86/kernel/irq_work.c:17 asm_sysvec_irq_work+0x1a/0x20 arch/x86/include/asm/idtentry.h:738 RIP: 0010:finish_task_switch+0x1ea/0x870 kernel/sched/core.c:5283 Code: c9 50 e8 f9 d0 0b 00 48 83 c4 08 4c 89 f7 e8 ed 38 00 00 0f 1f 44 00 00 4c 89 f7 e8 70 f7 2b 0a e8 4b cf 36 00 fb 48 8b 5d c0 <48> 8d bb f8 15 00 00 48 89 f8 48 c1 e8 03 49 be 00 00 00 00 00 fc RSP: 0018:ffffc90002f879a8 EFLAGS: 00000286 RAX: f1a633a953f52b00 RBX: ffff888063ea3c00 RCX: ffffffff94795603 RDX: dffffc0000000000 RSI: ffffffff8bcab5c0 RDI: ffffffff8c1fabe0 RBP: ffffc90002f879f0 R08: ffffffff8facda2f R09: 1ffffffff1f59b45 R10: dffffc0000000000 R11: fffffbfff1f59b46 R12: 1ffff11017287e77 R13: dffffc0000000000 R14: ffff8880b943e640 R15: ffff8880b943f3b8 context_switch kernel/sched/core.c:5412 [inline] __schedule+0x17f0/0x4a50 kernel/sched/core.c:6746 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7068 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_call_function_single+0x1a/0x20 arch/x86/include/asm/idtentry.h:709 RIP: 0010:constant_test_bit arch/x86/include/asm/bitops.h:206 [inline] RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:238 [inline] RIP: 0010:tif_need_resched include/linux/thread_info.h:184 [inline] RIP: 0010:need_resched include/linux/sched.h:2107 [inline] RIP: 0010:__schedule_loop kernel/sched/core.c:6825 [inline] RIP: 0010:schedule+0x155/0x320 kernel/sched/core.c:6838 Code: c1 eb 03 eb 0a 48 f7 45 00 08 00 00 00 74 2c bf 01 00 00 00 e8 7c 9a d4 f5 31 ff e8 55 b4 ff ff bf 01 00 00 00 e8 0b 9c d4 f5 <42> 80 3c 23 00 74 d4 48 89 ef e8 fc 3a 6a f6 eb ca 4c 8d 75 2c 4d RSP: 0018:ffffc90002f87d98 EFLAGS: 00000257 RAX: 0000000000000001 RBX: 1ffff1100c7d4780 RCX: 0000000000000001 RDX: dffffc0000000000 RSI: ffffffff8bcab5c0 RDI: 0000000000000001 RBP: ffff888063ea3c00 R08: ffffffff8facda2f R09: 1ffffffff1f59b45 R10: dffffc0000000000 R11: fffffbfff1f59b46 R12: dffffc0000000000 R13: ffff8880b943e1e0 R14: ffffffff8b910880 R15: ffff888063ea4e78 worker_thread+0xa2c/0xd70 kernel/workqueue.c:3408 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244