rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5356 rcu: (detected by 0, t=10502 jiffies, g=9617, q=575 ncpus=2) task:syz-executor.3 state:R running task stack:24336 pid:5356 tgid:5355 ppid:5107 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0x1796/0x49d0 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:kasan_check_range+0xc/0x290 mm/kasan/generic.c:188 Code: 0f 0b 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 55 41 57 41 56 41 54 53 01 48 85 f6 0f 84 a0 01 00 00 4c 8d 04 37 49 39 f8 0f 82 56 02 RSP: 0018:ffffc90004e56e50 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff81728ad0 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8fac1aa8 RBP: ffffc90004e56fb0 R08: ffffffff81cc7c49 R09: 1ffffd400032fe6e R10: dffffc0000000000 R11: fffff9400032fe6f R12: 1ffff920009caddc R13: ffffffff81cc7997 R14: ffffffff81cc7997 R15: dffffc0000000000 instrument_atomic_read include/linux/instrumented.h:68 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] cpumask_test_cpu include/linux/cpumask.h:571 [inline] cpu_online include/linux/cpumask.h:1181 [inline] trace_lock_release include/trace/events/lock.h:69 [inline] lock_release+0xb0/0x9f0 kernel/locking/lockdep.c:5765 rcu_lock_release include/linux/rcupdate.h:339 [inline] rcu_read_unlock include/linux/rcupdate.h:812 [inline] filemap_get_entry+0x452/0x4e0 mm/filemap.c:1858 __filemap_get_folio+0x65/0xbb0 mm/filemap.c:1885 grow_dev_folio fs/buffer.c:1049 [inline] grow_buffers fs/buffer.c:1115 [inline] __getblk_slow fs/buffer.c:1141 [inline] bdev_getblk+0x201/0x5a0 fs/buffer.c:1443 __bread_gfp+0x86/0x400 fs/buffer.c:1497 sb_bread include/linux/buffer_head.h:347 [inline] get_branch+0x2c3/0x6e0 fs/sysv/itree.c:102 get_block+0x180/0x16d0 fs/sysv/itree.c:222 block_read_full_folio+0x42e/0xe10 fs/buffer.c:2407 filemap_read_folio+0x1a0/0x790 mm/filemap.c:2355 do_read_cache_folio+0x134/0x820 mm/filemap.c:3788 do_read_cache_page+0x30/0x200 mm/filemap.c:3854 read_mapping_page include/linux/pagemap.h:896 [inline] dir_get_page fs/sysv/dir.c:64 [inline] sysv_find_entry+0x1af/0x410 fs/sysv/dir.c:157 sysv_inode_by_name+0x98/0x1f0 fs/sysv/dir.c:374 sysv_lookup+0x6b/0xe0 fs/sysv/namei.c:38 __lookup_slow+0x28c/0x3f0 fs/namei.c:1692 lookup_slow+0x53/0x70 fs/namei.c:1709 walk_component fs/namei.c:2004 [inline] link_path_walk+0x9ea/0xea0 fs/namei.c:2331 path_lookupat+0xa9/0x450 fs/namei.c:2492 filename_lookup+0x256/0x610 fs/namei.c:2522 user_path_at_empty+0x42/0x60 fs/namei.c:2929 user_path_at include/linux/namei.h:58 [inline] path_setxattr+0xb2/0x2a0 fs/xattr.c:666 __do_sys_lsetxattr fs/xattr.c:694 [inline] __se_sys_lsetxattr fs/xattr.c:690 [inline] __x64_sys_lsetxattr+0xb8/0xd0 fs/xattr.c:690 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: 0033:0x7f320707cf69 RSP: 002b:00007f3207e330c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000bd RAX: ffffffffffffffda RBX: 00007f32071b3f80 RCX: 00007f320707cf69 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000100 RBP: 00007f32070da6fe R08: 0000000000000002 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f32071b3f80 R15: 00007ffdb0ac3e18 rcu: rcu_preempt kthread starved for 10537 jiffies! g9617 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:25560 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0x1796/0x49d0 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0x14b/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+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/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: 5524 Comm: syz-executor.2 Not tainted 6.10.0-rc2-syzkaller-00064-g71d7b52cc33b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 RIP: 0010:validate_chain+0x84/0x5900 kernel/locking/lockdep.c:3825 Code: 81 5c b5 8d 48 c7 84 24 10 01 00 00 d0 15 73 81 48 8d 8c 24 00 01 00 00 48 c1 e9 03 48 b8 f1 f1 f1 f1 00 f2 f2 f2 4a 89 04 21 <48> b8 f2 f2 f2 00 f2 f2 f2 00 4a 89 44 21 09 4a 89 44 21 11 48 b8 RSP: 0018:ffffc90009c974e0 EFLAGS: 00000802 RAX: f2f2f200f1f1f1f1 RBX: ffffffff92c6d320 RCX: 1ffff92001392ebc RDX: 0000000000000001 RSI: ffff8880292ec6e0 RDI: ffff8880292ebc00 RBP: ffffc90009c977e0 R08: ffffffff92f725b7 R09: 1ffffffff25ee4b6 R10: dffffc0000000000 R11: fffffbfff25ee4b7 R12: dffffc0000000000 R13: ffff8880292ebc00 R14: ee5a7e9e6bab005e R15: ffff8880292ebc00 FS: 00007f47f742a6c0(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b32326000 CR3: 0000000068a66000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __might_fault+0xc6/0x120 mm/memory.c:6233 __copy_from_user include/linux/uaccess.h:97 [inline] check_xstate_in_sigframe arch/x86/kernel/fpu/signal.c:35 [inline] __fpu_restore_sig arch/x86/kernel/fpu/signal.c:348 [inline] fpu__restore_sig+0x1a1/0x11b0 arch/x86/kernel/fpu/signal.c:493 restore_sigcontext+0x675/0x7d0 arch/x86/kernel/signal_64.c:95 __do_sys_rt_sigreturn+0x17f/0x270 arch/x86/kernel/signal_64.c:263 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: 0033:0x7f47f667cf67 Code: 14 25 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 RSP: 002b:00007f47f742a178 EFLAGS: 00000246 RAX: 00000000000000ca RBX: 00007f47f67b3f88 RCX: 00007f47f667cf69 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f47f67b3f88 RBP: 00007f47f67b3f80 R08: 00007f47f742a6c0 R09: 00007f47f742a6c0 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f47f67b3f8c R13: 000000000000000b R14: 00007ffd3427cc60 R15: 00007ffd3427cd48