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INFO: rcu detected stall in shmem_fault (2)

Status: upstream: reported on 2024/06/03 20:13
Reported-by: syzbot+cf92cb07cc1063893ed7@syzkaller.appspotmail.com
First crash: 15d, last: 15d
▶ ▼ Similar bugs (7)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in shmem_fault (4) kernel 1 536d 536d 0/27 auto-obsoleted due to no activity on 2023/04/08 07:17
upstream INFO: rcu detected stall in shmem_fault mm 13 1919d 2079d 0/27 closed as dup on 2019/01/02 16:58
linux-6.1 INFO: rcu detected stall in shmem_fault 4 2d14h 12d 0/3 upstream: reported on 2024/06/07 10:17
upstream INFO: rcu detected stall in shmem_fault (5) cgroups mm 3 306d 326d 23/27 fixed on 2023/10/12 12:48
linux-5.15 INFO: rcu detected stall in shmem_fault 1 291d 291d 0/3 auto-obsoleted due to no activity on 2023/12/11 11:17
upstream INFO: rcu detected stall in shmem_fault (3) fs mm 4 785d 785d 0/27 auto-closed as invalid on 2022/06/25 08:10
upstream INFO: rcu detected stall in shmem_fault (2) cgroups mm 1 1659d 1659d 0/27 closed as invalid on 2019/12/04 14:04

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P3852/1:b..l
	(detected by 1, t=10502 jiffies, g=6769, q=516)
task:syz-executor.1  state:R  running task     stack:23992 pid: 3852 ppid:  3536 flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6780
 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:lock_acquire+0x252/0x4f0 kernel/locking/lockdep.c:5627
Code: 2b 00 74 08 4c 89 f7 e8 fc 7c 67 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25
RSP: 0018:ffffc90004c071e0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff92000980e48 RCX: 1ffff92000980de8
RDX: dffffc0000000000 RSI: ffffffff8a8b3c20 RDI: ffffffff8ad8f6c0
RBP: ffffc90004c07340 R08: dffffc0000000000 R09: fffffbfff1f7f019
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000980e44
R13: dffffc0000000000 R14: ffffc90004c07240 R15: 0000000000000246
 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:312
 rcu_read_lock include/linux/rcupdate.h:739 [inline]
 mapping_get_entry mm/filemap.c:1823 [inline]
 pagecache_get_page+0x15f/0x1010 mm/filemap.c:1894
 shmem_getpage_gfp+0x36c/0x3190 mm/shmem.c:1841
 shmem_fault+0x1d7/0x700 mm/shmem.c:2118
 __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
 populate_vma_page_range+0x215/0x2a0 mm/gup.c:1529
 __mm_populate+0x2a5/0x4a0 mm/gup.c:1638
 mm_populate include/linux/mm.h:2632 [inline]
 vm_mmap_pgoff+0x22b/0x2d0 mm/util.c:556
 ksys_mmap_pgoff+0x13e/0x780 mm/mmap.c:1624
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7ffadd8a9ee9
RSP: 002b:00007ffadbe1d0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007ffadd9e0fa0 RCX: 00007ffadd8a9ee9
RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000000020000000
RBP: 00007ffadd8f647f R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007ffadd9e0fa0 R15: 00007ffea3201ed8
 </TASK>
rcu: rcu_preempt kthread starved for 9619 jiffies! g6769 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:27192 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1f0 kernel/sched/core.c:6459
 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:300
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 1
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.15.160-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
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:110 [inline]
RIP: 0010:acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:570
Code: fd 58 f7 48 83 e3 08 0f 85 0a 01 00 00 4c 8d 74 24 20 e8 24 79 5f f7 0f 1f 44 00 00 e8 1a f9 58 f7 0f 00 2d 33 bb bb 00 fb f4 <4c> 89 f3 48 c1 eb 03 42 80 3c 3b 00 74 08 4c 89 f7 e8 8b c7 a2 f7
RSP: 0018:ffffc90000d67b00 EFLAGS: 000002d3
RAX: ffffffff8a2763a6 RBX: 0000000000000000 RCX: ffff88813fe70000
RDX: 0000000000000000 RSI: ffffffff8a8b2980 RDI: ffffffff8ad8f6c0
RBP: ffffc90000d67b90 R08: ffffffff8186dcf0 R09: ffffed1027fce001
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff920001acf60
R13: ffff88801863c804 R14: ffffc90000d67b20 R15: dffffc0000000000
 acpi_idle_enter+0x352/0x4f0 drivers/acpi/processor_idle.c:705
 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_secondary+0x371/0x500 arch/x86/kernel/smpboot.c:281
 secondary_startup_64_no_verify+0xb1/0xbb
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/03 20:12 linux-5.15.y c61bd26ae81a 0aba2352 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in shmem_fault
* Struck through repros no longer work on HEAD.