rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P9276/1:b..l rcu: (detected by 0, t=10503 jiffies, g=103669, q=170 ncpus=2) task:syz-executor.1 state:R running task stack:23232 pid:9276 tgid:9275 ppid:8726 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0xf15/0x5d00 kernel/sched/core.c:6745 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7067 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+0x1f2/0x560 kernel/locking/lockdep.c:5722 Code: c1 05 8a aa 96 7e 83 f8 01 0f 85 ea 02 00 00 9c 58 f6 c4 02 0f 85 d5 02 00 00 48 85 ed 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24 RSP: 0018:ffffc900034d73f0 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff9200069ae80 RCX: 000000001a19ab86 RDX: 0000000000000001 RSI: ffffffff8b2cae60 RDI: ffffffff8b8fcac0 RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff284be50 R10: ffffffff9425f287 R11: 0000000000000002 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff8dbb1760 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:329 [inline] rcu_read_lock include/linux/rcupdate.h:781 [inline] filemap_get_entry+0xdb/0x470 mm/filemap.c:1837 __filemap_get_folio+0x56/0xa80 mm/filemap.c:1885 __find_get_block_slow fs/buffer.c:203 [inline] __find_get_block fs/buffer.c:1410 [inline] __find_get_block+0x168/0xcb0 fs/buffer.c:1404 __getblk_slow+0x121/0x6a0 fs/buffer.c:1137 bdev_getblk+0xb1/0xc0 fs/buffer.c:1443 __bread_gfp+0xa9/0x370 fs/buffer.c:1497 sb_bread include/linux/buffer_head.h:347 [inline] get_branch+0x2cb/0x6c0 fs/sysv/itree.c:102 get_block+0x1a1/0x15a0 fs/sysv/itree.c:222 block_read_full_folio+0x38f/0xa70 fs/buffer.c:2407 filemap_read_folio+0xe5/0x2c0 mm/filemap.c:2355 do_read_cache_folio+0x203/0x540 mm/filemap.c:3788 do_read_cache_page mm/filemap.c:3854 [inline] read_cache_page+0x5b/0x160 mm/filemap.c:3863 read_mapping_page include/linux/pagemap.h:888 [inline] dir_get_page fs/sysv/dir.c:64 [inline] sysv_find_entry+0x1e5/0x690 fs/sysv/dir.c:157 sysv_inode_by_name+0x71/0x3b0 fs/sysv/dir.c:374 sysv_lookup fs/sysv/namei.c:38 [inline] sysv_lookup+0x8c/0x100 fs/sysv/namei.c:31 lookup_one_qstr_excl+0x11d/0x190 fs/namei.c:1607 filename_create+0x1ed/0x530 fs/namei.c:3901 do_mkdirat+0xab/0x3a0 fs/namei.c:4146 __do_sys_mkdirat fs/namei.c:4169 [inline] __se_sys_mkdirat fs/namei.c:4167 [inline] __x64_sys_mkdirat+0x114/0x170 fs/namei.c:4167 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb446c7cee9 RSP: 002b:00007fb4479c70c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007fb446dabf80 RCX: 00007fb446c7cee9 RDX: 0000000000000000 RSI: 0000000020002040 RDI: ffffffffffffff9c RBP: 00007fb446cc949e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007fb446dabf80 R15: 00007fff73db1768 rcu: rcu_preempt kthread starved for 10543 jiffies! g103669 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:26048 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0xf15/0x5d00 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6837 schedule_timeout+0x136/0x2a0 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2000 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2202 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: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 57 Comm: kworker/1:1H Not tainted 6.9.0-syzkaller-09699-geb6a9339efeb #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Workqueue: 0x0 (kblockd) RIP: 0010:lockdep_enabled kernel/locking/lockdep.c:116 [inline] RIP: 0010:lock_release+0xd3/0x6c0 kernel/locking/lockdep.c:5767 Code: 48 0f a3 1d 7f 0a 78 0e 0f 82 10 04 00 00 48 c7 c3 98 0d e4 8f 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 0f b6 14 02 <48> 89 d8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 d9 04 00 00 8b RSP: 0018:ffffc90000a18d98 EFLAGS: 00000802 RAX: dffffc0000000000 RBX: ffffffff8fe40d98 RCX: ffffffff816bd049 RDX: 0000000000000000 RSI: ffffffff8b8fca40 RDI: ffffffff8d4c6b48 RBP: 1ffff920001431b5 R08: 0000000000000000 R09: fffffbfff1fc7b5a R10: ffffffff8fe3dad7 R11: 0000000000000001 R12: ffffffff8dbb1760 R13: ffff88802ae95c80 R14: 000000000003d94c R15: ffff888012b02718 FS: 0000000000000000(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fcab51a8000 CR3: 0000000047bae000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lock_release include/linux/rcupdate.h:339 [inline] rcu_read_unlock include/linux/rcupdate.h:812 [inline] __lock_task_sighand+0x141/0x340 kernel/signal.c:1419 lock_task_sighand include/linux/sched/signal.h:746 [inline] do_send_sig_info kernel/signal.c:1300 [inline] group_send_sig_info+0x290/0x300 kernel/signal.c:1453 do_bpf_send_signal+0x9a/0x1d0 kernel/trace/bpf_trace.c:838 irq_work_single+0x1bc/0x260 kernel/irq_work.c:221 irq_work_run_list+0x92/0xc0 kernel/irq_work.c:252 irq_work_run+0x58/0xd0 kernel/irq_work.c:261 __sysvec_irq_work+0x8c/0x410 arch/x86/kernel/irq_work.c:22 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline] sysvec_irq_work+0x90/0xb0 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.isra.0+0x220/0xcc0 kernel/sched/core.c:5282 Code: a9 0a 00 00 44 8b 0d 17 ba 85 0e 45 85 c9 0f 85 c0 01 00 00 48 89 df e8 ae f8 ff ff e8 09 e6 36 00 fb 65 48 8b 1d a0 85 a5 7e <48> 8d bb f8 15 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 RSP: 0018:ffffc9000132fb30 EFLAGS: 00000202 RAX: 0000000000352dfb RBX: ffff88801aedda00 RCX: 1ffffffff1fc7309 RDX: 0000000000000000 RSI: ffffffff8b2cab60 RDI: ffffffff8b8fcac0 RBP: ffffc9000132fb78 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff8fe3dad7 R11: 0000000000000000 R12: ffff8880b933f978 R13: ffff888012b01e00 R14: 0000000000000000 R15: ffff8880b933ec00 context_switch kernel/sched/core.c:5411 [inline] __schedule+0xf1d/0x5d00 kernel/sched/core.c:6745 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7067 irqentry_exit+0x36/0x90 kernel/entry/common.c:354 asm_sysvec_call_function_single+0x1a/0x20 arch/x86/include/asm/idtentry.h:709 RIP: 0010:preempt_count_add+0xc/0x150 kernel/sched/core.c:5873 Code: 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 c7 c0 a0 db b3 94 55 <48> ba 00 00 00 00 00 fc ff df 48 89 c1 53 83 e0 07 89 fb 48 c1 e9 RSP: 0018:ffffc9000132fdf0 EFLAGS: 00000202 RAX: ffffffff94b3dba0 RBX: ffff88801aedda00 RCX: 0000000000000000 RDX: 0000000000000001 RSI: ffffffff8b2cab60 RDI: 0000000000000001 RBP: ffffed10035dbb40 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff8fe3dad7 R11: 0000000000000000 R12: ffff88801aedda2c R13: ffff88801aedda00 R14: ffffed10034d45e8 R15: fffffbfff1b01e40 __schedule_loop kernel/sched/core.c:6821 [inline] schedule+0xe0/0x350 kernel/sched/core.c:6837 worker_thread+0x2de/0xf70 kernel/workqueue.c:3408 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