rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6065/1:b..l rcu: (detected by 0, t=10502 jiffies, g=17665, q=862 ncpus=2) task:syz-executor.2 state:R running task stack:24464 pid:6065 tgid:6065 ppid:5332 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0x17e8/0x4a20 kernel/sched/core.c:6745 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7067 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:get_current arch/x86/include/asm/current.h:49 [inline] RIP: 0010:write_comp_data kernel/kcov.c:235 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x8/0x90 kernel/kcov.c:304 Code: 44 0a 20 e9 65 26 1a 0a 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 4c 8b 04 24 <65> 48 8b 14 25 00 d5 03 00 65 8b 05 30 ba 6d 7e a9 00 01 ff 00 74 RSP: 0018:ffffc90012957758 EFLAGS: 00000246 RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffff88805bd3bc00 RDX: dffffc0000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90012957810 R08: ffffffff81ea2622 R09: 1ffffffff25f50b0 R10: dffffc0000000000 R11: fffffbfff25f50b1 R12: 1ffff9200252aef0 R13: ffff88802c5356b8 R14: dffffc0000000000 R15: ffffc900129578a0 rcu_read_lock include/linux/rcupdate.h:782 [inline] __pte_offset_map+0xb2/0x380 mm/pgtable-generic.c:287 __pte_offset_map_lock+0xc7/0x300 mm/pgtable-generic.c:371 pte_offset_map_lock include/linux/mm.h:3020 [inline] __get_locked_pte mm/memory.c:1983 [inline] get_locked_pte include/linux/mm.h:2744 [inline] insert_page mm/memory.c:2030 [inline] vm_insert_page+0x645/0xaf0 mm/memory.c:2186 kcov_mmap+0xda/0x140 kernel/kcov.c:496 call_mmap include/linux/fs.h:2107 [inline] mmap_region+0xe91/0x2090 mm/mmap.c:2886 do_mmap+0x8ad/0xfa0 mm/mmap.c:1397 vm_mmap_pgoff+0x1dd/0x3d0 mm/util.c:573 ksys_mmap_pgoff+0x4f1/0x720 mm/mmap.c:1443 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fbb1d07cfa3 RSP: 002b:00007fff54920098 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007fbb1d1b42a8 RCX: 00007fbb1d07cfa3 RDX: 0000000000000003 RSI: 0000000000200000 RDI: 00007fbb1ae01000 RBP: 00007fbb1ae00000 R08: 00000000000000db R09: 0000000000000000 R10: 0000000000000011 R11: 0000000000000246 R12: 00007fff54920218 R13: 00007fff549201d0 R14: 00007fbb1d1b4210 R15: 00007fbb1d1b421c rcu: rcu_preempt kthread starved for 10543 jiffies! g17665 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:26448 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0x17e8/0x4a20 kernel/sched/core.c:6745 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7067 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:preempt_count_add+0x6/0x190 kernel/sched/core.c:5860 Code: 48 8b 3c 24 e8 3b 4d 96 00 eb 8c e9 ee fe ff ff 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 57 <41> 56 53 89 fb 48 c7 c0 e0 06 7a 94 48 c1 e8 03 49 bf 00 00 00 00 RSP: 0018:ffffc90000167b58 EFLAGS: 00000202 RAX: 0000000000000001 RBX: 1ffff11002ed9000 RCX: 0000000000000001 RDX: dffffc0000000000 RSI: ffffffff8bcaba80 RDI: 0000000000000001 RBP: ffff8880176c8000 R08: ffffffff8fad462f R09: 1ffffffff1f5a8c5 R10: dffffc0000000000 R11: fffffbfff1f5a8c6 R12: dffffc0000000000 R13: 1ffff9200002cf74 R14: ffffffff8b8f89a0 R15: ffff8880176c9278 __schedule_loop kernel/sched/core.c:6821 [inline] schedule+0x144/0x320 kernel/sched/core.c:6837 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x2df/0x1330 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: CPU: 0 PID: 1129 Comm: kworker/0:1H Not tainted 6.10.0-rc2-syzkaller-00010-g2ab795141095 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Workqueue: 0x0 (kblockd) RIP: 0010:finish_task_switch+0x1ea/0x870 kernel/sched/core.c:5282 Code: c9 50 e8 99 c9 0b 00 48 83 c4 08 4c 89 f7 e8 cd 38 00 00 e9 de 04 00 00 4c 89 f7 e8 60 97 2a 0a e8 5b f8 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:ffffc90003eef9c8 EFLAGS: 00000282 RAX: 9c98318878300100 RBX: ffff8880223d8000 RCX: ffffffff947a0603 RDX: dffffc0000000000 RSI: ffffffff8bcaba80 RDI: ffffffff8c1ff240 RBP: ffffc90003eefa10 R08: ffffffff8fad462f R09: 1ffffffff1f5a8c5 R10: dffffc0000000000 R11: fffffbfff1f5a8c6 R12: 1ffff11017287ea7 R13: dffffc0000000000 R14: ffff8880b943e7c0 R15: ffff8880b943f538 FS: 0000000000000000(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fff5491fe40 CR3: 0000000057dc4000 CR4: 0000000000350ef0 Call Trace: context_switch kernel/sched/core.c:5411 [inline] __schedule+0x17f0/0x4a20 kernel/sched/core.c:6745 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7067 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: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:2110 [inline] RIP: 0010:__schedule_loop kernel/sched/core.c:6824 [inline] RIP: 0010:schedule+0x15a/0x320 kernel/sched/core.c:6837 Code: 48 f7 45 00 08 00 00 00 74 2c bf 01 00 00 00 e8 dc fe d5 f5 31 ff e8 85 b4 ff ff bf 01 00 00 00 e8 6b 00 d6 f5 42 80 3c 23 00 <74> d4 48 89 ef e8 0c 4c 6c f6 eb ca 4c 8d 75 2c 4d 89 f5 49 c1 ed RSP: 0018:ffffc90003eefd98 EFLAGS: 00000246 RAX: 0000000000000001 RBX: 1ffff1100447b000 RCX: 0000000000000001 RDX: dffffc0000000000 RSI: ffffffff8bcaba80 RDI: 0000000000000001 RBP: ffff8880223d8000 R08: ffffffff8fad462f R09: 1ffffffff1f5a8c5 R10: dffffc0000000000 R11: fffffbfff1f5a8c6 R12: dffffc0000000000 R13: ffff8880b943e360 R14: ffffffff8b8f89a0 R15: ffff8880223d9278 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