rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (0 ticks this GP) idle=c2cc/1/0x4000000000000000 softirq=69264/69264 fqs=436 rcu: (detected by 0, t=10502 jiffies, g=64169, q=452 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 15960 Comm: syz.3.2285 Not tainted 6.12.0-syzkaller-09073-g9f16d5e6f220 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:task_wait_context kernel/locking/lockdep.c:5087 [inline] RIP: 0010:check_wait_context kernel/locking/lockdep.c:4871 [inline] RIP: 0010:__lock_acquire+0x130a/0x3c40 kernel/locking/lockdep.c:5176 Code: 0a 00 00 85 ff 0f 84 5b f6 ff ff ba 04 00 00 00 4c 89 fe 4c 89 ef e8 75 db ff ff 85 c0 0f 85 43 f6 ff ff 31 d2 e9 77 fb ff ff <41> be 03 00 00 00 e9 ce f2 ff ff c7 84 24 38 01 00 00 01 00 00 00 RSP: 0018:ffffc90000a18b38 EFLAGS: 00000002 RAX: 0000000000000003 RBX: 0000000000000005 RCX: ffff8880284a2fc0 RDX: 0000000000000000 RSI: 1ffff110050945e1 RDI: ffff8880284a2f08 RBP: dffffc0000000000 R08: 0000000000000005 R09: fffffbfff2dc93cc R10: ffffffff96e49e67 R11: 0000000000000006 R12: ffff8880284a2fe1 R13: ffff8880284a2440 R14: 0000000000000001 R15: ffff8880284a2fe8 FS: 00007fa84cfce6c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c3077ef CR3: 0000000079552000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] advance_sched+0xd8/0xc60 net/sched/sch_taprio.c:924 __run_hrtimer kernel/time/hrtimer.c:1739 [inline] __hrtimer_run_queues+0x20a/0xae0 kernel/time/hrtimer.c:1803 hrtimer_interrupt+0x392/0x8e0 kernel/time/hrtimer.c:1865 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x10f/0x400 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:rcu_preempt_read_enter kernel/rcu/tree_plugin.h:390 [inline] RIP: 0010:__rcu_read_lock+0x72/0xf0 kernel/rcu/tree_plugin.h:413 Code: 8d bd 44 04 00 00 8b 9b 44 04 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c3 01 <83> c0 03 38 d0 7c 04 84 d2 75 61 48 b8 00 00 00 00 00 fc ff df 89 RSP: 0018:ffffc9001084f628 EFLAGS: 00000202 RAX: 0000000000000004 RBX: 0000000000000004 RCX: ffffc9000fc43000 RDX: 0000000000000000 RSI: ffffffff81c4684e RDI: ffff8880284a2884 RBP: ffff8880284a2440 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000004 R12: 000000000000039f R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff92002109ef7 rcu_read_lock include/linux/rcupdate.h:847 [inline] page_ref_add_unless.constprop.0+0x13/0x390 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:3506 filemap_map_pages+0x648/0x16b0 mm/filemap.c:3687 do_fault_around mm/memory.c:5280 [inline] do_read_fault mm/memory.c:5313 [inline] do_fault mm/memory.c:5456 [inline] do_pte_missing+0xdab/0x3e70 mm/memory.c:3979 handle_pte_fault mm/memory.c:5801 [inline] __handle_mm_fault+0x103c/0x2a40 mm/memory.c:5944 handle_mm_fault+0x3fa/0xaa0 mm/memory.c:6112 faultin_page mm/gup.c:1187 [inline] __get_user_pages+0x8d9/0x3b50 mm/gup.c:1485 populate_vma_page_range+0x27f/0x3a0 mm/gup.c:1923 __mm_populate+0x1d6/0x380 mm/gup.c:2026 mm_populate include/linux/mm.h:3385 [inline] vm_mmap_pgoff+0x293/0x360 mm/util.c:593 ksys_mmap_pgoff+0x7d/0x5c0 mm/mmap.c:542 __do_sys_mmap arch/x86/kernel/sys_x86_64.c:89 [inline] __se_sys_mmap arch/x86/kernel/sys_x86_64.c:82 [inline] __x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:82 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: 0033:0x7fa84c17e819 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:00007fa84cfce038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007fa84c335fa0 RCX: 00007fa84c17e819 RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000000020000000 RBP: 00007fa84c1f175e R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fa84c335fa0 R15: 00007ffe1cee2b88 rcu: rcu_preempt kthread starved for 9629 jiffies! g64169 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:28272 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0xe58/0x5ad0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6848 schedule_timeout+0x124/0x280 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2045 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2247 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: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.12.0-syzkaller-09073-g9f16d5e6f220 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 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 98 cd de 74 48 8b 00 a8 08 75 0c 66 90 0f 00 2d 88 6e b7 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: 0000:ffffffff8de07d70 EFLAGS: 00000246 RAX: 0000000000004000 RBX: 0000000000000001 RCX: ffffffff8b24ee99 RDX: 0000000000000001 RSI: ffff888020a91000 RDI: ffff888020a91064 RBP: ffff888020a91064 R08: 0000000000000001 R09: ffffed10170c6fed R10: ffff8880b8637f6b R11: 0000000000000000 R12: ffff88801ffe2800 R13: ffffffff8ee01820 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7ffcb60354 CR3: 0000000025912000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: acpi_idle_enter+0xc5/0x160 drivers/acpi/processor_idle.c:699 cpuidle_enter_state+0xaa/0x4f0 drivers/cpuidle/cpuidle.c:268 cpuidle_enter+0x4e/0xa0 drivers/cpuidle/cpuidle.c:389 cpuidle_idle_call kernel/sched/idle.c:230 [inline] do_idle+0x310/0x3f0 kernel/sched/idle.c:325 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:423 rest_init+0x16b/0x2b0 init/main.c:747 start_kernel+0x3e4/0x4d0 init/main.c:1102 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:507 x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:488 common_startup_64+0x13e/0x148