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INFO: rcu detected stall in filemap_fault

Status: auto-obsoleted due to no activity on 2024/12/02 14:29
Reported-by: syzbot+235989af305bc41facc5@syzkaller.appspotmail.com
First crash: 323d, last: 320d
▶ ▼ Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in filemap_fault (3) mm 1 13 98d 378d 0/29 auto-obsoleted due to no activity on 2025/07/02 21:11
upstream INFO: rcu detected stall in filemap_fault mm 1 1 2468d 2466d 0/29 closed as dup on 2019/01/02 16:20
upstream INFO: rcu detected stall in filemap_fault (2) mm fs 1 7 1339d 1360d 0/29 auto-closed as invalid on 2022/02/07 21:39
linux-5.15 INFO: rcu detected stall in filemap_fault (2) 1 4 29d 133d 0/3 upstream: reported on 2025/02/27 13:48
linux-6.1 INFO: rcu detected stall in filemap_fault 1 2 298d 308d 0/3 auto-obsoleted due to no activity on 2024/12/24 06:37

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P3699/2:b..l
	(detected by 0, t=10502 jiffies, g=4925, q=741)
task:syz.1.2         state:R  running task     stack:21984 pid: 3699 ppid:  3568 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6777
 irqentry_exit+0x53/0x80 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:85 [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+0x7b/0x290 mm/kasan/generic.c:189
Code: 00 00 00 00 fc ff df 4f 8d 34 1a 4c 89 f5 4c 29 cd 48 83 fd 10 7f 26 48 85 ed 0f 84 3a 01 00 00 49 f7 d2 49 01 da 41 80 39 00 <0f> 85 c4 01 00 00 49 ff c1 49 ff c2 75 ee e9 1d 01 00 00 45 89 cf
RSP: 0018:ffffc90003076758 EFLAGS: 00000246
RAX: 0000000000000001 RBX: 1ffffffff1bd2a55 RCX: ffffffff8162adbc
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8de952a8
RBP: 0000000000000001 R08: dffffc0000000000 R09: fffffbfff1bd2a55
R10: ffffffffffffffff R11: dffffc0000000001 R12: 1ffff9200060ecf8
R13: dffffc0000000000 R14: fffffbfff1bd2a56 R15: ffff88807b68c000
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
 cpumask_test_cpu include/linux/cpumask.h:344 [inline]
 cpu_online include/linux/cpumask.h:895 [inline]
 trace_lock_acquire include/trace/events/lock.h:13 [inline]
 lock_acquire+0xcc/0x4f0 kernel/locking/lockdep.c:5594
 rcu_lock_acquire+0x20/0x30 include/linux/rcupdate.h:312
 rcu_read_lock include/linux/rcupdate.h:739 [inline]
 percpu_ref_tryget_many include/linux/percpu-refcount.h:241 [inline]
 percpu_ref_tryget+0x10/0x140 include/linux/percpu-refcount.h:266
 css_tryget include/linux/cgroup.h:355 [inline]
 get_mem_cgroup_from_mm+0xd9/0x260 mm/memcontrol.c:991
 __mem_cgroup_charge+0x12/0x80 mm/memcontrol.c:6777
 mem_cgroup_charge include/linux/memcontrol.h:700 [inline]
 __add_to_page_cache_locked+0xbdb/0x11a0 mm/filemap.c:892
 add_to_page_cache_lru+0x1b3/0x560 mm/filemap.c:984
 page_cache_ra_unbounded+0x403/0x930 mm/readahead.c:222
 page_cache_async_readahead include/linux/pagemap.h:856 [inline]
 do_async_mmap_readahead mm/filemap.c:3023 [inline]
 filemap_fault+0x669/0x1470 mm/filemap.c:3079
 __do_fault+0x139/0x340 mm/memory.c:3898
 do_read_fault mm/memory.c:4234 [inline]
 do_fault mm/memory.c:4362 [inline]
 handle_pte_fault mm/memory.c:4621 [inline]
 __handle_mm_fault mm/memory.c:4756 [inline]
 handle_mm_fault+0x376f/0x5950 mm/memory.c:4854
 faultin_page mm/gup.c:976 [inline]
 __get_user_pages+0x4ed/0x11d0 mm/gup.c:1197
 __get_user_pages_locked mm/gup.c:1382 [inline]
 get_dump_page+0x1ad/0x8a0 mm/gup.c:1838
 dump_user_range+0x64/0x320 fs/coredump.c:945
 elf_core_dump+0x3c7d/0x4570 fs/binfmt_elf.c:2285
 do_coredump+0x1852/0x31e0 fs/coredump.c:826
 get_signal+0xc06/0x14e0 kernel/signal.c:2883
 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
 irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:320
 exc_page_fault+0x342/0x700 arch/x86/mm/fault.c:1504
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:568
RIP: 0033:0x7f4c5878be81
RSP: 002b:ffffffffffffffd0 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007f4c58927f80 RCX: 00007f4c5878be79
RDX: 0000000000000000 RSI: ffffffffffffffd0 RDI: 0000000000000000
RBP: 00007f4c587f993e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f4c58927f80 R15: 00007ffd4b9737b8
 </TASK>
rcu: rcu_preempt kthread starved for 9330 jiffies! g4925 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:26712 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 0
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.15.165-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_check_gp_kthread_starvation+0x1d2/0x240 kernel/rcu/tree_stall.h:487
 print_other_cpu_stall+0x137a/0x14d0 kernel/rcu/tree_stall.h:592
 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
 rcu_pending kernel/rcu/tree.c:3932 [inline]
 rcu_sched_clock_irq+0xa38/0x1150 kernel/rcu/tree.c:2619
 update_process_times+0x196/0x200 kernel/time/timer.c:1818
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1686 [inline]
 __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:22 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline]
RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:132 [inline]
RIP: 0010:acpi_safe_halt drivers/acpi/processor_idle.c:109 [inline]
RIP: 0010:acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:562
Code: 8a 43 f7 48 83 e3 08 0f 85 0a 01 00 00 4c 8d 74 24 20 e8 24 07 4a f7 0f 1f 44 00 00 e8 8a 86 43 f7 0f 00 2d c3 50 a6 00 fb f4 <4c> 89 f3 48 c1 eb 03 42 80 3c 3b 00 74 08 4c 89 f7 e8 bb 4f 8d f7
RSP: 0018:ffffffff8c607b80 EFLAGS: 000002d3
RAX: ffffffff8a3cdb16 RBX: 0000000000000000 RCX: ffffffff8c6bd5c0
RDX: 0000000000000000 RSI: ffffffff8a8b2a20 RDI: ffffffff8ad8f7c0
RBP: ffffffff8c607c10 R08: ffffffff8186e260 R09: fffffbfff18d7ab9
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffffffff18c0f70
R13: ffff888019600004 R14: ffffffff8c607ba0 R15: dffffc0000000000
 acpi_idle_enter+0x352/0x4f0 drivers/acpi/processor_idle.c:697
 cpuidle_enter_state+0x521/0xef0 drivers/cpuidle/cpuidle.c:237
 cpuidle_enter+0x59/0x90 drivers/cpuidle/cpuidle.c:351
 call_cpuidle kernel/sched/idle.c:158 [inline]
 cpuidle_idle_call kernel/sched/idle.c:239 [inline]
 do_idle+0x3e4/0x670 kernel/sched/idle.c:306
 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403
 start_kernel+0x48c/0x540 init/main.c:1140
 secondary_startup_64_no_verify+0xb1/0xbb
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/08/24 14:28 linux-5.15.y fa93fa65db6e d7d32352 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in filemap_fault
2024/08/21 15:27 linux-5.15.y fa93fa65db6e db5852f9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in filemap_fault
* Struck through repros no longer work on HEAD.