rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4732/1:b..l P4734/1:b..l (detected by 0, t=10502 jiffies, g=11697, q=147 ncpus=2) task:syz.5.24 state:R running task stack:26688 pid:4734 ppid:4443 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10e9/0x40d0 kernel/sched/core.c:6561 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873 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:__sanitizer_cov_trace_const_cmp8+0x0/0x80 kernel/kcov.c:321 Code: 28 4d 39 ca 77 22 89 ff 89 f6 49 ff c0 4c 89 01 48 c7 44 11 08 05 00 00 00 48 89 7c 11 10 48 89 74 11 18 48 89 44 11 20 c3 90 <48> 8b 04 24 65 48 8b 0d 44 94 81 7e 65 8b 15 45 94 81 7e 81 e2 00 RSP: 0018:ffffc90003597878 EFLAGS: 00000246 RAX: 1ffff11004db8bc0 RBX: ffff888026dc5c0e RCX: ffff88802be83b80 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90003597a50 R08: ffff88802be83b80 R09: 0000000000000003 R10: 0000000000000003 R11: 0000000000000000 R12: dffffc0000000000 R13: ffff888026dc5e80 R14: 0000000000000001 R15: 0000000000000001 ma_is_root lib/maple_tree.c:337 [inline] mte_is_root lib/maple_tree.c:342 [inline] mas_validate_limits lib/maple_tree.c:7109 [inline] mt_validate+0x1902/0x4c90 lib/maple_tree.c:7239 validate_mm_mt+0xcd/0x420 mm/mmap.c:294 validate_mm+0xcc/0x2b0 mm/mmap.c:331 do_mmap+0xc7/0xf30 mm/mmap.c:1261 vm_mmap_pgoff+0x1b2/0x2b0 mm/util.c:520 ksys_mmap_pgoff+0x516/0x6f0 mm/mmap.c:1470 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f5dfbf8e9a3 RSP: 002b:00007ffd6bbfb4d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 0000000000400000 RCX: 00007f5dfbf8e9a3 RDX: 0000000000000003 RSI: 00000000003c0000 RDI: 0000001b2ff60000 RBP: 0000001b2ff60000 R08: 0000000000000004 R09: 0000000000040000 R10: 0000000000000011 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f5dfc17d260 R14: 0000000000000003 R15: 00007ffd6bbfb7c0 task:syz.2.99 state:R running task stack:25248 pid:4732 ppid:4264 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10e9/0x40d0 kernel/sched/core.c:6561 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873 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:84 [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+0x74/0x290 mm/kasan/generic.c:189 Code: df 4f 8d 0c 03 48 8d 5c 37 ff 48 c1 eb 03 4e 8d 14 3b 4d 89 d6 4d 29 ce 49 83 fe 10 7f 26 4d 85 f6 0f 84 39 01 00 00 48 f7 d3 <4c> 01 db 41 80 39 00 0f 85 c1 01 00 00 49 ff c1 48 ff c3 75 ee e9 RSP: 0018:ffffc9000354f4f0 EFLAGS: 00000202 RAX: 1ffffffff2d78f01 RBX: e0000eeff0add6c2 RCX: ffffffff83f4ab6f RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff88807a9149e8 RBP: 0000000000000000 R08: dffffc0000000000 R09: ffffed100f52293d R10: ffffed100f52293e R11: 1ffff1100f52293d R12: dffffc0000000000 R13: 00000000000009b8 R14: 0000000000000001 R15: dffffc0000000001 instrument_atomic_read include/linux/instrumented.h:72 [inline] atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline] blk_cgroup_congested+0xff/0x220 block/blk-cgroup.c:2014 __cgroup_throttle_swaprate+0x6d/0x1a0 mm/swapfile.c:3671 cgroup_throttle_swaprate include/linux/swap.h:662 [inline] folio_throttle_swaprate include/linux/swap.h:671 [inline] shmem_add_to_page_cache+0x9c1/0x1c00 mm/shmem.c:717 shmem_get_folio_gfp+0x158b/0x3400 mm/shmem.c:1971 shmem_fault+0x1be/0x7b0 mm/shmem.c:2156 __do_fault+0x13b/0x4e0 mm/memory.c:4280 do_read_fault mm/memory.c:4631 [inline] do_fault mm/memory.c:4760 [inline] handle_pte_fault mm/memory.c:5031 [inline] __handle_mm_fault mm/memory.c:5173 [inline] handle_mm_fault+0x28ca/0x3e70 mm/memory.c:5294 faultin_page mm/gup.c:1026 [inline] __get_user_pages+0x3ff/0xeb0 mm/gup.c:1250 populate_vma_page_range+0x214/0x2b0 mm/gup.c:1607 __mm_populate+0x248/0x370 mm/gup.c:1721 mm_populate include/linux/mm.h:2823 [inline] vm_mmap_pgoff+0x203/0x2b0 mm/util.c:525 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fe15a38e969 RSP: 002b:00007fe15b219038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007fe15a5b5fa0 RCX: 00007fe15a38e969 RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000200000000000 RBP: 00007fe15a410ab1 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fe15a5b5fa0 R15: 00007ffd573ab5f8 rcu: rcu_preempt kthread starved for 10572 jiffies! g11697 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:27840 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10e9/0x40d0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1965 rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706 rcu_gp_kthread+0x95/0x380 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: 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:51 [inline] NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline] NMI backtrace for cpu 1 skipped: idling at default_idle+0xb/0x10 arch/x86/kernel/process.c:735