rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P13848/1:b..l P28151/1:b..l (detected by 1, t=10502 jiffies, g=89065, q=185 ncpus=2) task:udevadm state:R running task stack:24656 pid:28151 ppid:25552 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6874 irqentry_exit+0x63/0x70 kernel/entry/common.c:439 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:85 [inline] RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline] RIP: 0010:kasan_check_range+0x84/0x290 mm/kasan/generic.c:189 Code: 49 c1 e9 03 4b 8d 1c 21 49 89 df 4d 29 df 49 83 ff 10 7f 29 4d 85 ff 0f 84 38 01 00 00 4c 89 cb 48 f7 d3 4c 01 f3 41 80 3b 00 <0f> 85 86 01 00 00 49 ff c3 48 ff c3 75 ee e9 18 01 00 00 44 89 dd RSP: 0018:ffffc900039f7430 EFLAGS: 00000246 RAX: ffffc900039f7501 RBX: fffffffffffffffe RCX: ffffffff8a1b9202 RDX: 0000000000000001 RSI: 0000000000000010 RDI: ffffc900039f7550 RBP: 0000000000000000 R08: ffffc900039f755f R09: 1ffff9200073eeab R10: dffffc0000000000 R11: fffff5200073eeaa R12: dffffc0000000001 R13: 1ffff1100fd0c980 R14: 1ffff9200073eeaa R15: 0000000000000002 memset+0x1e/0x40 mm/kasan/shadow.c:44 mt_validate_nulls lib/maple_tree.c:7182 [inline] mt_validate+0x3ec2/0x4cb0 lib/maple_tree.c:7249 validate_mm_mt+0xe2/0x440 mm/mmap.c:295 __split_vma+0x30/0x500 mm/mmap.c:2355 do_mas_align_munmap+0x397/0x12b0 mm/mmap.c:2480 do_mas_munmap+0x240/0x2b0 mm/mmap.c:2650 __mmap_region mm/mmap.c:2698 [inline] mmap_region+0x6e0/0x1ca0 mm/mmap.c:2916 do_mmap+0x964/0xfd0 mm/mmap.c:1436 vm_mmap_pgoff+0x1c1/0x2d0 mm/util.c:520 ksys_mmap_pgoff+0x516/0x6f0 mm/mmap.c:1482 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fab60e2a242 RSP: 002b:00007fff07141e18 EFLAGS: 00000206 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007fab60d81000 RCX: 00007fab60e2a242 RDX: 0000000000000005 RSI: 000000000001c000 RDI: 00007fab60d81000 RBP: 0000000000000812 R08: 0000000000000003 R09: 0000000000008000 R10: 0000000000000812 R11: 0000000000000206 R12: 00007fff07141e68 R13: 00007fab60e065f0 R14: 00007fff07142290 R15: 00000fffe0e283c6 task:syz-executor state:R running task stack:22448 pid:13848 ppid:13318 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 preempt_schedule_notrace+0xd9/0x120 kernel/sched/core.c:6824 preempt_schedule_notrace_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:35 rcu_is_watching+0x76/0xa0 kernel/rcu/tree.c:722 rcu_read_unlock include/linux/rcupdate.h:820 [inline] page_ext_put+0x2b/0xb0 mm/page_ext.c:182 page_table_check_free include/linux/page_table_check.h:46 [inline] free_pages_prepare mm/page_alloc.c:1487 [inline] free_pcp_prepare mm/page_alloc.c:1536 [inline] free_unref_page_prepare+0x8c4/0x9a0 mm/page_alloc.c:3413 free_unref_page_list+0xbb/0x8e0 mm/page_alloc.c:3554 release_pages+0x1fa6/0x2220 mm/swap.c:1035 __pagevec_release+0x6d/0xe0 mm/swap.c:1055 pagevec_release include/linux/pagevec.h:71 [inline] folio_batch_release include/linux/pagevec.h:135 [inline] shmem_undo_range+0x7c2/0x20c0 mm/shmem.c:946 shmem_truncate_range mm/shmem.c:1062 [inline] shmem_evict_inode+0x25b/0xa80 mm/shmem.c:1171 evict+0x4c9/0x8d0 fs/inode.c:705 do_unlinkat+0x388/0x580 fs/namei.c:4405 __do_sys_unlink fs/namei.c:4446 [inline] __se_sys_unlink fs/namei.c:4444 [inline] __x64_sys_unlink+0x45/0x50 fs/namei.c:4444 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fe03d59bf47 RSP: 002b:00007ffded329648 EFLAGS: 00000206 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fe03d59bf47 RDX: 00007ffded329670 RSI: 00007ffded329700 RDI: 00007ffded329700 RBP: 00007ffded329700 R08: 00007ffded32a700 R09: 00000000ffffffff R10: 0000000000000100 R11: 0000000000000206 R12: 00007ffded32a790 R13: 00007fe03d6321ca R14: 00000000000e90ea R15: 00007ffded32a7d0 rcu: rcu_preempt kthread timer wakeup didn't happen for 10569 jiffies! g89065 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=68003 rcu: rcu_preempt kthread starved for 10570 jiffies! g89065 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:26864 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 schedule+0xb9/0x180 kernel/sched/core.c:6638 schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2168 rcu_gp_fqs_loop+0x303/0x1340 kernel/rcu/tree.c:1706 rcu_gp_kthread+0x99/0x3b0 kernel/rcu/tree.c:1905 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 PID: 28013 Comm: syz.5.2806 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:lock_acquire+0x225/0x4a0 kernel/locking/lockdep.c:5666 Code: f7 84 24 80 00 00 00 00 02 00 00 43 c6 44 3d 04 f8 0f 85 f0 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 44 3d 00 00 00 00 00 43 c7 44 3d 08 00 00 00 00 65 48 8b 04 RSP: 0018:ffffc90004f1e200 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 0000000000000000 RCX: c8cf5c5a212be500 RDX: 0000000000000000 RSI: ffffffff8a8c2b20 RDI: ffffffff8adf1ba0 RBP: ffffc90004f1e318 R08: dffffc0000000000 R09: 1ffffffff215f471 R10: dffffc0000000000 R11: fffffbfff215f472 R12: 0000000000000001 R13: 1ffff920009e3c4c R14: 0000000000000246 R15: dffffc0000000000 FS: 00007f52e4cfa6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fab60dfe250 CR3: 000000007523b000 CR4: 00000000003506e0 DR0: 00000000c88e006c DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] wait_for_commit+0x2f9/0x480 fs/btrfs/transaction.c:877 btrfs_commit_transaction+0x5a6/0x39d0 fs/btrfs/transaction.c:2268 try_flush_qgroup+0x2bc/0x350 fs/btrfs/qgroup.c:3783 __btrfs_qgroup_reserve_meta+0x58/0xa0 fs/btrfs/qgroup.c:4080 btrfs_qgroup_reserve_meta_prealloc fs/btrfs/qgroup.h:384 [inline] start_transaction+0x358/0x11c0 fs/btrfs/transaction.c:593 btrfs_dirty_inode+0x139/0x1c0 fs/btrfs/inode.c:6293 inode_update_time fs/inode.c:1958 [inline] touch_atime+0x2f8/0x640 fs/inode.c:2031 file_accessed include/linux/fs.h:2600 [inline] filemap_read+0x2da3/0x3020 mm/filemap.c:2836 __kernel_read+0x2ec/0x6d0 fs/read_write.c:428 integrity_kernel_read+0x86/0xd0 security/integrity/iint.c:228 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:485 [inline] ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline] ima_calc_file_hash+0x910/0x1900 security/integrity/ima/ima_crypto.c:573 ima_collect_measurement+0x503/0xb50 security/integrity/ima/ima_api.c:293 process_measurement+0x1183/0x1c30 security/integrity/ima/ima_main.c:351 ima_file_check+0xc8/0x110 security/integrity/ima/ima_main.c:534 do_open fs/namei.c:3636 [inline] path_openat+0x26e8/0x2ee0 fs/namei.c:3791 do_filp_open+0x1f1/0x430 fs/namei.c:3818 do_sys_openat2+0x150/0x4b0 fs/open.c:1320 do_sys_open fs/open.c:1336 [inline] __do_sys_openat fs/open.c:1352 [inline] __se_sys_openat fs/open.c:1347 [inline] __x64_sys_openat+0x135/0x160 fs/open.c:1347 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f52e3d9ce59 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f52e4cfa028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f52e4015fa0 RCX: 00007f52e3d9ce59 RDX: 0000000000000042 RSI: 0000200000000100 RDI: ffffffffffffff9c RBP: 00007f52e3e32d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f52e4016038 R14: 00007f52e4015fa0 R15: 00007ffe0a189328