rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=fb24/1/0x4000000000000000 softirq=28257/28268 fqs=0 rcu: (detected by 0, t=10506 jiffies, g=20329, q=343 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 6087 Comm: syz-executor Not tainted 6.15.0-rc2-syzkaller-00404-g8560697b23dc #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:memset+0xf/0x20 arch/x86/lib/memset_64.S:38 Code: 44 88 1f e9 6e 77 e0 f4 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 49 89 f9 40 88 f0 48 89 d1 aa 4c 89 c8 e9 42 77 e0 f4 0f 1f 80 00 00 00 00 90 90 90 90 90 RSP: 0018:ffffc90000a08cd0 EFLAGS: 00000002 RAX: ffffffff8c2b6200 RBX: 1ffff110170e4f02 RCX: 0000000000000012 RDX: 0000000000000018 RSI: 0000000000000000 RDI: ffff88807e11d346 RBP: 1ffff1100fc23a68 R08: ffff88807e11d357 R09: ffff88807e11d340 R10: dffffc0000000000 R11: ffffed100fc23a6b R12: ffff8880b8727810 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff88807e11d340 FS: 000055556d842500(0000) GS:ffff88812509a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd841ae56c0 CR3: 0000000051464000 CR4: 0000000000350ef0 Call Trace: rb_link_node include/linux/rbtree.h:63 [inline] rb_add_cached include/linux/rbtree.h:182 [inline] timerqueue_add+0x200/0x290 lib/timerqueue.c:40 __run_hrtimer kernel/time/hrtimer.c:1778 [inline] __hrtimer_run_queues+0x6d6/0xd40 kernel/time/hrtimer.c:1825 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1887 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x112/0x420 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:get_current arch/x86/include/asm/current.h:25 [inline] RIP: 0010:write_comp_data kernel/kcov.c:245 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x8/0x90 kernel/kcov.c:314 Code: 44 0a 20 e9 e5 80 4d ff 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 4c 8b 04 24 <65> 48 8b 14 25 08 60 68 93 65 8b 05 d8 9f a5 11 25 00 01 ff 00 74 RSP: 0018:ffffc90004abf2d8 EFLAGS: 00000293 RAX: ffffffff82139027 RBX: 000000000000001d RCX: ffff88802fae9e00 RDX: 0000000000000000 RSI: 000000000000001d RDI: 000000000000001f RBP: ffffc90004abf610 R08: ffffffff8213693b R09: 1ffff1100529efa4 R10: dffffc0000000000 R11: ffffed100529efa5 R12: 00007fd841a9d000 R13: 00007fd841a9c000 R14: ffffc90004abf4f0 R15: dffffc0000000000 copy_pte_range+0x3db/0x6680 mm/memory.c:1131 copy_pmd_range mm/memory.c:1255 [inline] copy_pud_range mm/memory.c:1292 [inline] copy_p4d_range mm/memory.c:1316 [inline] copy_page_range+0xe57/0x13a0 mm/memory.c:1410 dup_mmap kernel/fork.c:726 [inline] dup_mm kernel/fork.c:1734 [inline] copy_mm+0x130d/0x22c0 kernel/fork.c:1786 copy_process+0x17de/0x3d10 kernel/fork.c:2429 kernel_clone+0x242/0x930 kernel/fork.c:2844 __do_sys_clone kernel/fork.c:2987 [inline] __se_sys_clone kernel/fork.c:2971 [inline] __x64_sys_clone+0x268/0x2e0 kernel/fork.c:2971 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd840d849d3 Code: 1f 84 00 00 00 00 00 64 48 8b 04 25 10 00 00 00 45 31 c0 31 d2 31 f6 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 89 c2 85 c0 75 2c 64 48 8b 04 25 10 00 00 RSP: 002b:00007ffedfa8c148 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fd840d849d3 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001 R10: 000055556d8427d0 R11: 0000000000000246 R12: 0000000000000000 R13: 00000000000927c0 R14: 000000000002b137 R15: 00007ffedfa8c2e0 rcu: rcu_preempt kthread starved for 10506 jiffies! g20329 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:26976 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1b88/0x5240 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x163/0x360 kernel/sched/core.c:6860 schedule_timeout+0x15b/0x2b0 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x2e1/0x1340 kernel/rcu/tree.c:2046 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2248 kthread+0x7b9/0x940 kernel/kthread.c:464 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 UID: 0 PID: 7921 Comm: syz.5.572 Not tainted 6.15.0-rc2-syzkaller-00404-g8560697b23dc #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:rep_nop arch/x86/include/asm/vdso/processor.h:13 [inline] RIP: 0010:cpu_relax arch/x86/include/asm/vdso/processor.h:18 [inline] RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0x1baa/0x2d40 kernel/smp.c:885 Code: b6 04 03 84 c0 75 7e 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 68 dc 0b 00 41 83 e4 01 4c 8b 64 24 68 75 07 e8 18 d8 0b 00 eb 41 90 48 b8 00 00 00 00 00 fc ff df 0f b6 04 03 84 c0 75 11 41 f7 RSP: 0018:ffffc90003817780 EFLAGS: 00000246 RAX: ffffffff81b6e40d RBX: 1ffff110170e7e91 RCX: 0000000000080000 RDX: ffffc9000c362000 RSI: 000000000007ffff RDI: 0000000000080000 RBP: ffffc90003817968 R08: ffffffff81b6e3d8 R09: 1ffffffff20bfc8e R10: dffffc0000000000 R11: fffffbfff20bfc8f R12: ffff8880b863ad08 R13: ffff8880b873f488 R14: ffff8880b863ad00 R15: 0000000000000001 FS: 00007f9ed43386c0(0000) GS:ffff888124f9a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9ed3570c40 CR3: 0000000028336000 CR4: 0000000000350ef0 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052 kill_bdev block/bdev.c:90 [inline] set_blocksize+0x39b/0x410 block/bdev.c:175 sb_set_blocksize+0xb5/0x180 block/bdev.c:186 init_nilfs+0x55d/0x790 fs/nilfs2/the_nilfs.c:750 nilfs_fill_super+0x10b/0x7b0 fs/nilfs2/super.c:1060 nilfs_get_tree+0x4fb/0x920 fs/nilfs2/super.c:1228 vfs_get_tree+0x92/0x2b0 fs/super.c:1759 do_new_mount+0x2cf/0xb70 fs/namespace.c:3881 do_mount fs/namespace.c:4221 [inline] __do_sys_mount fs/namespace.c:4432 [inline] __se_sys_mount+0x38c/0x400 fs/namespace.c:4409 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9ed358f90a Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 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:00007f9ed4337e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f9ed4337ef0 RCX: 00007f9ed358f90a RDX: 000020000000b900 RSI: 0000200000000f00 RDI: 00007f9ed4337eb0 RBP: 000020000000b900 R08: 00007f9ed4337ef0 R09: 0000000003210052 R10: 0000000003210052 R11: 0000000000000246 R12: 0000200000000f00 R13: 00007f9ed4337eb0 R14: 0000000000000ebd R15: 000020000000b800