rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P9010/1:b..l P9768/1:b..l rcu: (detected by 0, t=10502 jiffies, g=43757, q=283 ncpus=2) task:syz.4.864 state:R running task stack:27696 pid:9768 tgid:9766 ppid:8881 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0xe37/0x5490 kernel/sched/core.c:6529 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:6851 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:5727 Code: c1 05 0a 10 9a 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:ffffc900034f7678 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff9200069eed1 RCX: 0000000000000001 RDX: 0000000000000001 RSI: ffffffff8b4cc7c0 RDI: ffffffff8bb09880 RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff28c56e0 R10: ffffffff9462b707 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff8ddb5be0 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:326 [inline] rcu_read_lock include/linux/rcupdate.h:838 [inline] count_memcg_event_mm.part.0+0x37/0x340 include/linux/memcontrol.h:1017 count_memcg_event_mm include/linux/memcontrol.h:561 [inline] mm_account_fault mm/memory.c:5698 [inline] handle_mm_fault+0x1b5/0x7b0 mm/memory.c:5858 faultin_page mm/gup.c:1194 [inline] __get_user_pages+0x475/0x15c0 mm/gup.c:1493 __get_user_pages_locked mm/gup.c:1760 [inline] __gup_longterm_locked+0x22e/0x1b30 mm/gup.c:2489 pin_user_pages_remote+0xee/0x150 mm/gup.c:3528 process_vm_rw_single_vec mm/process_vm_access.c:106 [inline] process_vm_rw_core.constprop.0+0x439/0x9f0 mm/process_vm_access.c:216 process_vm_rw+0x301/0x360 mm/process_vm_access.c:284 __do_sys_process_vm_readv mm/process_vm_access.c:296 [inline] __se_sys_process_vm_readv mm/process_vm_access.c:292 [inline] __x64_sys_process_vm_readv+0xe2/0x1c0 mm/process_vm_access.c:292 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: 0033:0x7f6707379e79 RSP: 002b:00007f670815d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000136 RAX: ffffffffffffffda RBX: 00007f6707515f80 RCX: 00007f6707379e79 RDX: 0000000000000002 RSI: 0000000020008400 RDI: 00000000000000b8 RBP: 00007f67073e793e R08: 0000000000000286 R09: 0000000000000000 R10: 0000000020008640 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f6707515f80 R15: 00007fff9b1b23b8 task:syz.0.703 state:R running task stack:24672 pid:9010 tgid:9006 ppid:7246 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0xe37/0x5490 kernel/sched/core.c:6529 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:6851 irqentry_exit+0x36/0x90 kernel/entry/common.c:354 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x0/0x20 kernel/kcov.c:319 Code: 0c 24 89 f2 89 fe bf 05 00 00 00 e9 2a fe ff 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 0f 1e fa 48 8b 0c 24 48 89 f2 48 89 fe bf 07 00 00 00 e9 f8 fd RSP: 0018:ffffc900030f6fe8 EFLAGS: 00000246 RAX: 0000000000040000 RBX: ffffc900030f7090 RCX: ffffc900099f2000 RDX: 0000000000040000 RSI: 0000000000000003 RDI: 0000000000000002 RBP: 0000000000000003 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000000 R12: 0000000000000003 R13: ffffc900030f70a8 R14: ffff88807bb9af80 R15: 00000000000001c4 xa_is_err include/linux/xarray.h:207 [inline] xa_err include/linux/xarray.h:226 [inline] xas_error include/linux/xarray.h:1431 [inline] xas_start+0x5e/0x790 lib/xarray.c:187 xas_load+0x22/0x5b0 lib/xarray.c:238 filemap_get_entry+0x10a/0x3c0 mm/filemap.c:1840 shmem_get_folio_gfp+0x226/0x15e0 mm/shmem.c:2104 shmem_fault+0x205/0xaf0 mm/shmem.c:2388 __do_fault+0x10a/0x490 mm/memory.c:4655 do_shared_fault mm/memory.c:5121 [inline] do_fault mm/memory.c:5195 [inline] do_pte_missing mm/memory.c:3947 [inline] handle_pte_fault mm/memory.c:5521 [inline] __handle_mm_fault+0x3cc8/0x55b0 mm/memory.c:5664 handle_mm_fault+0x44e/0x7b0 mm/memory.c:5832 do_user_addr_fault+0x7a3/0x13f0 arch/x86/mm/fault.c:1389 handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0010:rep_movs_alternative+0x4a/0x70 arch/x86/lib/copy_user_64.S:71 Code: 75 f1 c3 cc cc cc cc 66 0f 1f 84 00 00 00 00 00 48 8b 06 48 89 07 48 83 c6 08 48 83 c7 08 83 e9 08 74 df 83 f9 08 73 e8 eb c9 a4 c3 cc cc cc cc 48 89 c8 48 c1 e9 03 83 e0 07 f3 48 a5 89 c1 RSP: 0018:ffffc900030f76a0 EFLAGS: 00050206 RAX: 0000000000000001 RBX: 0000000000001000 RCX: 0000000000001000 RDX: 0000000000000000 RSI: ffff88806be9e000 RDI: 00000000201c4000 RBP: 00000000201c4000 R08: 0000000000000000 R09: ffffed100d7d3dff R10: ffff88806be9efff R11: 0000000000000000 R12: ffffc900030f7b38 R13: 00000000201c5000 R14: ffff88806be9e000 R15: 0000000000000000 copy_user_generic arch/x86/include/asm/uaccess_64.h:110 [inline] raw_copy_to_user arch/x86/include/asm/uaccess_64.h:131 [inline] copy_to_user_iter lib/iov_iter.c:25 [inline] iterate_ubuf include/linux/iov_iter.h:29 [inline] iterate_and_advance2 include/linux/iov_iter.h:245 [inline] iterate_and_advance include/linux/iov_iter.h:271 [inline] _copy_to_iter+0x37e/0x1150 lib/iov_iter.c:185 copy_page_to_iter lib/iov_iter.c:362 [inline] copy_page_to_iter+0xf1/0x180 lib/iov_iter.c:349 copy_folio_to_iter include/linux/uio.h:180 [inline] filemap_read+0x69f/0xd10 mm/filemap.c:2676 blkdev_read_iter+0x18d/0x490 block/fops.c:764 aio_read+0x31c/0x4e0 fs/aio.c:1602 __io_submit_one fs/aio.c:2003 [inline] io_submit_one+0x1586/0x1db0 fs/aio.c:2052 __do_sys_io_submit fs/aio.c:2111 [inline] __se_sys_io_submit fs/aio.c:2081 [inline] __x64_sys_io_submit+0x19d/0x330 fs/aio.c:2081 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: 0033:0x7f165e579e79 RSP: 002b:00007f165f2aa038 EFLAGS: 00000246 ORIG_RAX: 00000000000000d1 RAX: ffffffffffffffda RBX: 00007f165e716058 RCX: 00007f165e579e79 RDX: 00000000200000c0 RSI: 00000000000000ca RDI: 00007f165f289000 RBP: 00007f165e5e793e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f165e716058 R15: 00007ffe043e6158 rcu: rcu_preempt kthread starved for 10585 jiffies! g43757 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:27584 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0xe37/0x5490 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6621 schedule_timeout+0x136/0x2a0 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2034 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2236 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 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:111