rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (0 ticks this GP) idle=34ac/1/0x4000000000000000 softirq=135623/135623 fqs=0 rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P25927/1:b..l P25925/1:b..l P25932/3:b..l rcu: (detected by 0, t=10506 jiffies, g=133565, q=433 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 24512 Comm: syz-executor Not tainted 6.14.0-rc2-syzkaller-00281-g496659003dac #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 RIP: 0010:__remove_hrtimer+0xa5/0x290 kernel/time/hrtimer.c:1133 Code: 41 5c 41 5d 41 5e 41 5f e9 68 dc 12 00 e8 63 dc 12 00 48 8d 7d 50 48 89 de e8 97 44 ac 09 31 ff 41 89 c4 89 c6 e8 eb d6 12 00 <45> 84 e4 0f 85 84 00 00 00 e8 3d dc 12 00 48 8d 7d 08 48 b8 00 00 RSP: 0018:ffffc90000a18df8 EFLAGS: 00000046 RAX: 0000000080010001 RBX: ffff88807432a340 RCX: ffffffff81a6fad5 RDX: ffff888046528000 RSI: 0000000000000000 RDI: 0000000000000001 RBP: ffff8880b872c780 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000002 R12: 0000000000000000 R13: 0000000000000000 R14: ffff8880b872c680 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c2ba998 CR3: 0000000025266000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __run_hrtimer kernel/time/hrtimer.c:1781 [inline] __hrtimer_run_queues+0x50b/0xae0 kernel/time/hrtimer.c:1865 hrtimer_interrupt+0x392/0x8e0 kernel/time/hrtimer.c:1927 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:get_stack_info+0x3d/0xb0 arch/x86/kernel/dumpstack_64.c:208 Code: 1d c8 15 a7 7e 48 85 f6 74 03 48 89 f3 48 85 ff 74 6d 4c 89 e2 48 89 de e8 b0 fe f9 09 84 c0 74 5e 4d 85 ed 74 1f 41 8b 2c 24 <83> fd 3f 0f 87 0e 69 c3 ff 49 8b 45 00 48 0f a3 e8 72 15 48 0f ab RSP: 0018:ffffc9000cd976a8 EFLAGS: 00000282 RAX: 0000000000000001 RBX: ffff888046528000 RCX: ffffc9000cd98000 RDX: ffffc9000cd97720 RSI: ffff888046528000 RDI: ffffc9000cd976d0 RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000 R10: ffffc9000cd97720 R11: 0000000000000000 R12: ffffc9000cd97720 R13: ffffc9000cd97740 R14: ffffc9000cd97720 R15: ffffc9000cd97748 __unwind_start+0x3f6/0x7f0 arch/x86/kernel/unwind_orc.c:729 unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0x74/0x100 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122 save_stack+0x162/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x8d/0x400 mm/page_owner.c:297 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_frozen_pages+0x6db/0xfb0 mm/page_alloc.c:2660 vfree+0x174/0x950 mm/vmalloc.c:3383 kcov_put kernel/kcov.c:439 [inline] kcov_put+0x2a/0x40 kernel/kcov.c:435 kcov_close+0xd/0x20 kernel/kcov.c:535 __fput+0x3ff/0xb70 fs/file_table.c:464 task_work_run+0x14e/0x250 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xad8/0x2d70 kernel/exit.c:938 do_group_exit+0xd3/0x2a0 kernel/exit.c:1087 get_signal+0x24ed/0x26c0 kernel/signal.c:3036 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fabce38c9eb Code: Unable to access opcode bytes at 0x7fabce38c9c1. RSP: 002b:00007ffe3fee4240 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: 0000000000000000 RBX: 000000000000425f RCX: 00007fabce38c9eb RDX: 00007ffe3fee42b8 RSI: 0000000040086602 RDI: 0000000000000005 RBP: 00007ffe3fee4350 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe3fee53e0 R13: 00007fabce40e08c R14: 000055556a0224a8 R15: 0000000000000005 task:syz.1.4842 state:R running task stack:27936 pid:25932 tgid:25932 ppid:24094 task_flags:0x400040 flags:0x00000000 Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6764 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6943 preempt_schedule_thunk+0x1a/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] filemap_map_pages+0xe4e/0x16b0 mm/filemap.c:3823 do_fault_around mm/memory.c:5350 [inline] do_read_fault mm/memory.c:5383 [inline] do_fault mm/memory.c:5526 [inline] do_pte_missing+0xdb8/0x3e10 mm/memory.c:4047 handle_pte_fault mm/memory.c:5889 [inline] __handle_mm_fault+0x1166/0x2c60 mm/memory.c:6032 handle_mm_fault+0x3fa/0xaa0 mm/memory.c:6201 do_user_addr_fault+0x60d/0x13f0 arch/x86/mm/fault.c:1337 handle_page_fault arch/x86/mm/fault.c:1480 [inline] exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1538 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7fb27186d2fd RSP: 002b:00007ffd9ef6fc40 EFLAGS: 00010202 RAX: 000000110c2b8000 RBX: 00007fb2726d5720 RCX: 0000000000000007 RDX: 0000000000001e3a RSI: 0000000000000978 RDI: 0000000000000080 RBP: ffffffff81f25e3a R08: 00007fb271ba6038 R09: 00007fb271b92000 R10: 00007fb270fff008 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff81f250be R15: 0000000000000313 task:syz-executor state:R running task stack:25232 pid:25925 tgid:25925 ppid:5803 task_flags:0x400000 flags:0x00000000 Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6764 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6943 preempt_schedule_thunk+0x1a/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] insert_page mm/memory.c:2163 [inline] vm_insert_page+0x45d/0x6d0 mm/memory.c:2312 kcov_mmap+0xd7/0x150 kernel/kcov.c:506 call_mmap include/linux/fs.h:2245 [inline] mmap_file mm/internal.h:124 [inline] __mmap_new_file_vma mm/vma.c:2292 [inline] __mmap_new_vma mm/vma.c:2356 [inline] __mmap_region+0x181f/0x2760 mm/vma.c:2457 mmap_region+0x32b/0x3f0 mm/vma.c:2535 do_mmap+0xd8d/0x11b0 mm/mmap.c:561 vm_mmap_pgoff+0x203/0x3a0 mm/util.c:575 ksys_mmap_pgoff+0x32c/0x5c0 mm/mmap.c:607 __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: 0033:0x7f46d0d8ce23 RSP: 002b:00007ffde5565878 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f46d0fa5f40 RCX: 00007f46d0d8ce23 RDX: 0000000000000003 RSI: 0000000000800000 RDI: 00007f46cf3f9000 RBP: 00007f46d0fa6738 R08: 00000000000000d7 R09: 0000000000000000 R10: 0000000000000011 R11: 0000000000000246 R12: 0000000000000008 R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000 task:syz.7.4838 state:R running task stack:26704 pid:25927 tgid:25926 ppid:24582 task_flags:0x400140 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6764 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7086 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.part.0+0x155/0x380 kernel/locking/lockdep.c:5816 Code: b8 ff ff ff ff 65 0f c1 05 10 dc 6b 7e 83 f8 01 0f 85 d0 01 00 00 9c 58 f6 c4 02 0f 85 e5 01 00 00 48 85 ed 0f 85 b6 01 00 00 <48> b8 00 00 00 00 00 fc ff df 48 01 c3 48 c7 03 00 00 00 00 48 c7 RSP: 0018:ffffc9000fe17460 EFLAGS: 00000206 RAX: 0000000000000046 RBX: 1ffff92001fc2e8d RCX: 000000009f2502c7 RDX: 0000000000000001 RSI: ffffffff8b6cf020 RDI: ffffffff8bd353c0 RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff2dd7f98 R10: ffffffff96ebfcc7 R11: 0000000000000001 R12: 0000000000000000 R13: ffffffff8e1bcc80 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] filemap_get_entry+0xd6/0x3c0 mm/filemap.c:1857 shmem_get_folio_gfp+0x221/0x1530 mm/shmem.c:2446 shmem_fault+0x200/0xae0 mm/shmem.c:2723 __do_fault+0x10a/0x490 mm/memory.c:4977 do_read_fault mm/memory.c:5392 [inline] do_fault mm/memory.c:5526 [inline] do_pte_missing+0xecf/0x3e10 mm/memory.c:4047 handle_pte_fault mm/memory.c:5889 [inline] __handle_mm_fault+0x1166/0x2c60 mm/memory.c:6032 handle_mm_fault+0x3fa/0xaa0 mm/memory.c:6201 faultin_page mm/gup.c:1196 [inline] __get_user_pages+0x773/0x36f0 mm/gup.c:1491 populate_vma_page_range+0x27f/0x3a0 mm/gup.c:1929 __mm_populate+0x1d6/0x380 mm/gup.c:2032 mm_populate include/linux/mm.h:3386 [inline] vm_mmap_pgoff+0x2d3/0x3a0 mm/util.c:580 ksys_mmap_pgoff+0x7d/0x5c0 mm/mmap.c:607 __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: 0033:0x7fa38318cde9 RSP: 002b:00007fa383f60038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007fa3833a5fa0 RCX: 00007fa38318cde9 RDX: b635773f07ebbeee RSI: 0000000000b36000 RDI: 0000400000000000 RBP: 00007fa38320e2a0 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fa3833a5fa0 R15: 00007ffdd3247d78 rcu: rcu_preempt kthread timer wakeup didn't happen for 10505 jiffies! g133565 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=106501 rcu: rcu_preempt kthread starved for 10506 jiffies! g133565 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27552 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6764 __schedule_loop kernel/sched/core.c:6841 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6856 schedule_timeout+0x124/0x280 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2024 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2226 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244