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INFO: rcu detected stall in shmem_fault (4)

Status: auto-obsoleted due to no activity on 2023/04/08 07:17
Subsystems: kernel
[Documentation on labels]
First crash: 484d, last: 484d
▶ ▼ Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in shmem_fault mm 13 1867d 2027d 0/26 closed as dup on 2019/01/02 16:58
upstream INFO: rcu detected stall in shmem_fault (5) cgroups mm 3 254d 274d 23/26 fixed on 2023/10/12 12:48
linux-5.15 INFO: rcu detected stall in shmem_fault 1 238d 238d 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 732d 733d 0/26 auto-closed as invalid on 2022/06/25 08:10
upstream INFO: rcu detected stall in shmem_fault (2) cgroups mm 1 1606d 1606d 0/26 closed as invalid on 2019/12/04 14:04

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=c25c/1/0x4000000000000000 softirq=99397/99398 fqs=105
	(detected by 0, t=10502 jiffies, g=121013, q=177 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 2821 Comm: syz-executor.3 Not tainted 6.2.0-rc1-next-20221226-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
RIP: 0010:check_kcov_mode kernel/kcov.c:173 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0xb/0x70 kernel/kcov.c:207
Code: 0f 1e fa 48 8b be a8 01 00 00 e8 b0 ff ff ff 31 c0 c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 f3 0f 1e fa 65 8b 05 2d a6 82 7e <89> c1 48 8b 34 24 81 e1 00 01 00 00 65 48 8b 14 25 00 ac 03 00 a9
RSP: 0018:ffffc900001e0de0 EFLAGS: 00000097
RAX: 0000000080010002 RBX: ffff8880b992b880 RCX: ffffffff81708d04
RDX: ffff888026cb1d40 RSI: 0000000000000000 RDI: 0000000000000005
RBP: ffff88807932b340 R08: 0000000000000005 R09: 000000000000001f
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000001
R13: 0000000000000001 R14: 0000000000000000 R15: ffff88807932b340
FS:  00007f4e84b8b700(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fadc67abf84 CR3: 0000000027f0d000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 enqueue_hrtimer+0x113/0x470 kernel/time/hrtimer.c:1086
 __run_hrtimer kernel/time/hrtimer.c:1702 [inline]
 __hrtimer_run_queues+0xa40/0xcc0 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x320/0x790 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1096 [inline]
 __sysvec_apic_timer_interrupt+0x180/0x640 arch/x86/kernel/apic/apic.c:1113
 sysvec_apic_timer_interrupt+0x92/0xc0 arch/x86/kernel/apic/apic.c:1107
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649
RIP: 0010:finish_task_switch.isra.0+0x2bf/0xc80 kernel/sched/core.c:5123
Code: 8b 3a 4c 89 e7 48 c7 02 00 00 00 00 ff d1 4d 85 ff 75 bf 4c 89 e7 e8 10 f8 ff ff e8 ab bd 30 00 fb 65 48 8b 1c 25 00 ac 03 00 <48> 8d bb 48 15 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1
RSP: 0018:ffffc90005bced10 EFLAGS: 00000202
RAX: 0000000000000801 RBX: ffff888026cb1d40 RCX: 1ffffffff226b0ce
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90005bced58 R08: 0000000000000001 R09: ffffffff91344af7
R10: 0000000000000001 R11: 0000000000000000 R12: ffff8880b993b580
R13: ffff88802a4dd7c0 R14: 0000000000000000 R15: ffff8880b993bfb8
 context_switch kernel/sched/core.c:5247 [inline]
 __schedule+0x254c/0x53f0 kernel/sched/core.c:6555
 preempt_schedule_irq+0x52/0xa0 kernel/sched/core.c:6867
 irqentry_exit+0x35/0x80 kernel/entry/common.c:432
 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:654
RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:55 [inline]
RIP: 0010:__unwind_start+0x546/0x800 arch/x86/kernel/unwind_orc.c:734
Code: dd ff ff 4c 89 f8 48 c1 e8 03 0f b6 04 28 84 c0 74 08 3c 03 0f 8e 2d 01 00 00 41 8b 07 85 c0 0f 84 89 fd ff ff 41 80 7d 00 00 <0f> 85 3d 01 00 00 41 80 3c 24 00 49 8b 47 08 0f 85 15 01 00 00 48
RSP: 0018:ffffc90005bcefc8 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffffc90005bcf0a0 RCX: 0000000000000000
RDX: 0000000080000000 RSI: ffffc90005bcf0a0 RDI: 0000000000000001
RBP: dffffc0000000000 R08: ffffffff8ef5f01c R09: ffffc90005bcf04c
R10: fffff52000b79e0e R11: ffffc90005bcf0a8 R12: fffff52000b79e05
R13: fffff52000b79e04 R14: ffffc90005bcf050 R15: ffffc90005bcf018
 unwind_start arch/x86/include/asm/unwind.h:64 [inline]
 arch_stack_walk+0x60/0xf0 arch/x86/kernel/stacktrace.c:24
 stack_trace_save+0x90/0xc0 kernel/stacktrace.c:122
 save_stack+0x151/0x1e0 mm/page_owner.c:127
 __set_page_owner+0x1f/0x60 mm/page_owner.c:190
 prep_new_page mm/page_alloc.c:2546 [inline]
 get_page_from_freelist+0x119e/0x2a80 mm/page_alloc.c:4298
 __alloc_pages+0x1cb/0x5b0 mm/page_alloc.c:5564
 __folio_alloc+0x16/0x40 mm/page_alloc.c:5596
 vma_alloc_folio+0x155/0x870 mm/mempolicy.c:2243
 shmem_alloc_folio+0xfe/0x1d0 mm/shmem.c:1577
 shmem_alloc_and_acct_folio+0x15e/0x5d0 mm/shmem.c:1601
 shmem_get_folio_gfp+0xb2e/0x1a30 mm/shmem.c:1939
 shmem_fault+0x1cc/0x8b0 mm/shmem.c:2154
 __do_fault+0x107/0x600 mm/memory.c:4174
 do_read_fault mm/memory.c:4525 [inline]
 do_fault mm/memory.c:4654 [inline]
 handle_pte_fault mm/memory.c:4942 [inline]
 __handle_mm_fault+0x22f2/0x3c90 mm/memory.c:5084
 handle_mm_fault+0x1b6/0x850 mm/memory.c:5230
 faultin_page mm/gup.c:926 [inline]
 __get_user_pages+0x4f8/0xfc0 mm/gup.c:1153
 populate_vma_page_range+0x241/0x320 mm/gup.c:1526
 __mm_populate+0x105/0x3b0 mm/gup.c:1640
 mm_populate include/linux/mm.h:2860 [inline]
 vm_mmap_pgoff+0x201/0x280 mm/util.c:547
 ksys_mmap_pgoff+0x7d/0x5a0 mm/mmap.c:1457
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f4e83e8c0a9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f4e84b8b168 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f4e83fac050 RCX: 00007f4e83e8c0a9
RDX: 0000000000000002 RSI: 0000000000b36000 RDI: 0000000020000000
RBP: 00007f4e83ee7ae9 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe49d6afbf R14: 00007f4e84b8b300 R15: 0000000000022000
 </TASK>
rcu: rcu_preempt kthread starved for 10291 jiffies! g121013 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:28672 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x2544/0x53f0 kernel/sched/core.c:6555
 schedule+0xde/0x1b0 kernel/sched/core.c:6631
 schedule_timeout+0x14e/0x2a0 kernel/time/timer.c:2167
 rcu_gp_fqs_loop+0x190/0x910 kernel/rcu/tree.c:1656
 rcu_gp_kthread+0x23a/0x360 kernel/rcu/tree.c:1855
 kthread+0x2e8/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 PID: 12986 Comm: kworker/0:43 Not tainted 6.2.0-rc1-next-20221226-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Workqueue: events fqdir_free_fn
RIP: 0010:check_kcov_mode kernel/kcov.c:173 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x11/0x70 kernel/kcov.c:207
Code: a8 01 00 00 e8 b0 ff ff ff 31 c0 c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 f3 0f 1e fa 65 8b 05 2d a6 82 7e 89 c1 48 8b 34 24 <81> e1 00 01 00 00 65 48 8b 14 25 00 ac 03 00 a9 00 01 ff 00 74 0e
RSP: 0018:ffffc9000ae3fb38 EFLAGS: 00000202
RAX: 0000000000000001 RBX: 1ffff920015c7f6c RCX: 0000000000000001
RDX: ffff888082473a80 RSI: ffffffff81761fdd RDI: 0000000000000005
RBP: ffffc9000ae3fc58 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000002
FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbe921821b8 CR3: 000000003c2f0000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 rep_nop arch/x86/include/asm/vdso/processor.h:13 [inline]
 cpu_relax arch/x86/include/asm/vdso/processor.h:18 [inline]
 csd_lock_wait kernel/smp.c:413 [inline]
 smp_call_function_single+0x1fd/0x680 kernel/smp.c:776
 rcu_barrier+0x296/0x6d0 kernel/rcu/tree.c:4049
 fqdir_free_fn+0x32/0x160 net/ipv4/inet_fragment.c:164
 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289
 worker_thread+0x669/0x1090 kernel/workqueue.c:2436
 kthread+0x2e8/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/12/31 06:24 linux-next c76083fac3ba ab32d508 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in shmem_fault
* Struck through repros no longer work on HEAD.