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INFO: rcu detected stall in ext4_release_file (2)

Status: upstream: reported C repro on 2024/05/30 03:27
Subsystems: mm ext4
[Documentation on labels]
Reported-by: syzbot+9c703233282a4a1a6749@syzkaller.appspotmail.com
First crash: 261d, last: 82d
Cause bisection: failed (error log, bisect log)
  
Fix bisection: fixed by (bisect log) :
commit ae94b263f5f69c180347e795fbefa051b65aacc3
Author: Dmitry Vyukov <dvyukov@google.com>
Date: Tue Jun 11 07:50:33 2024 +0000

  x86: Ignore stack unwinding in KCOV

  
▶ ▼ Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [mm?] [ext4?] INFO: rcu detected stall in ext4_release_file (2) 0 (2) 2024/10/01 15:05
▶ ▼ Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in ext4_release_file kernel 2 1253d 1264d 0/28 auto-closed as invalid on 2021/09/15 05:15
linux-5.15 INFO: rcu detected stall in ext4_release_file 1 148d 148d 0/3 auto-obsoleted due to no activity on 2024/10/04 05:35
android-5-15 BUG: soft lockup in ext4_release_file 1 213d 213d 0/2 auto-obsoleted due to no activity on 2024/07/20 19:54
▶ ▼ Last patch testing requests (1)
Created Duration User Patch Repo Result
2024/06/09 08:42 17m retest repro upstream report log
▶ ▼ Fix bisection attempts (3)
Created Duration User Patch Repo Result
2024/10/01 06:59 8h05m bisect fix upstream OK (1) job log
2024/08/31 01:08 2h42m bisect fix upstream OK (0) job log log
2024/07/31 18:17 3h22m bisect fix upstream OK (0) job log log

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P9865/1:b..l P9506/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=34833, q=848 ncpus=2)
task:syz.3.1363      state:R  running task     stack:20536 pid:9506  tgid:9506  ppid:5095   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5408 [inline]
 __schedule+0x17e8/0x4a20 kernel/sched/core.c:6745
 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7067
 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:PagePoisoned include/linux/page-flags.h:296 [inline]
RIP: 0010:page_to_nid include/linux/mm.h:1664 [inline]
RIP: 0010:page_zone include/linux/mm.h:1879 [inline]
RIP: 0010:folio_zone include/linux/mm.h:1889 [inline]
RIP: 0010:zone_stat_mod_folio include/linux/vmstat.h:439 [inline]
RIP: 0010:__folio_start_writeback+0x96d/0x11a0 mm/page-writeback.c:3112
Code: 85 e4 75 16 e8 f4 47 c6 ff eb 15 e8 ed 47 c6 ff e8 08 f9 b5 09 4d 85 e4 74 ea e8 de 47 c6 ff fb 48 b8 00 00 00 00 00 fc ff df <48> 8b 4c 24 08 80 3c 01 00 74 08 4c 89 f7 e8 b0 f4 2b 00 49 8b 1e
RSP: 0018:ffffc9000434ecc0 EFLAGS: 00000293
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffff88802037da00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000434ee38 R08: ffffffff81cfdd88 R09: 1ffffffff25f4ec4
R10: dffffc0000000000 R11: fffffbfff25f4ec5 R12: 0000000000000200
R13: 1ffff92000869da4 R14: ffffea00016d0400 R15: 0000000000000046
 ext4_bio_write_folio+0x1062/0x1da0 fs/ext4/page-io.c:554
 mpage_submit_folio+0x1af/0x230 fs/ext4/inode.c:1869
 mpage_map_and_submit_buffers fs/ext4/inode.c:2115 [inline]
 mpage_map_and_submit_extent fs/ext4/inode.c:2254 [inline]
 ext4_do_writepages+0x1db0/0x3d40 fs/ext4/inode.c:2679
 ext4_writepages+0x213/0x3c0 fs/ext4/inode.c:2768
 do_writepages+0x35b/0x870 mm/page-writeback.c:2634
 filemap_fdatawrite_wbc+0x125/0x180 mm/filemap.c:397
 __filemap_fdatawrite_range mm/filemap.c:430 [inline]
 __filemap_fdatawrite mm/filemap.c:436 [inline]
 filemap_flush+0xdf/0x130 mm/filemap.c:463
 ext4_release_file+0x81/0x300 fs/ext4/file.c:169
 __fput+0x408/0x8b0 fs/file_table.c:422
 task_work_run+0x251/0x310 kernel/task_work.c:180
 exit_task_work include/linux/task_work.h:38 [inline]
 do_exit+0xa27/0x27e0 kernel/exit.c:874
 do_group_exit+0x207/0x2c0 kernel/exit.c:1023
 get_signal+0x16a1/0x1740 kernel/signal.c:2909
 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 irqentry_exit_to_user_mode+0x79/0x280 kernel/entry/common.c:231
 exc_page_fault+0x590/0x8c0 arch/x86/mm/fault.c:1542
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x7f9472d75d41
RSP: 002b:0000000000000010 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007f9472f03fa0 RCX: 00007f9472d75d39
RDX: 0000000020000040 RSI: 0000000000000010 RDI: 0000000002480480
RBP: 00007f9472df6766 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 000000000000000b R14: 00007f9472f03fa0 R15: 00007ffdb087f9f8
 </TASK>
task:syz.1.1484      state:R  running task     stack:24528 pid:9865  tgid:9864  ppid:8100   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5408 [inline]
 __schedule+0x17e8/0x4a20 kernel/sched/core.c:6745
 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6924
 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6948
 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12
 unwind_next_frame+0x2124/0x2a00 arch/x86/kernel/unwind_orc.c:672
 arch_stack_walk+0x151/0x1b0 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122
 save_stack+0xfb/0x1f0 mm/page_owner.c:156
 __reset_page_owner+0x75/0x3f0 mm/page_owner.c:297
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1088 [inline]
 free_unref_folios+0xf23/0x19e0 mm/page_alloc.c:2632
 folios_put_refs+0x93a/0xa60 mm/swap.c:1024
 free_pages_and_swap_cache+0x2ea/0x690 mm/swap_state.c:329
 __tlb_batch_free_encoded_pages mm/mmu_gather.c:136 [inline]
 tlb_batch_pages_flush mm/mmu_gather.c:149 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:366 [inline]
 tlb_flush_mmu+0x3a3/0x680 mm/mmu_gather.c:373
 zap_pte_range mm/memory.c:1685 [inline]
 zap_pmd_range mm/memory.c:1724 [inline]
 zap_pud_range mm/memory.c:1753 [inline]
 zap_p4d_range mm/memory.c:1774 [inline]
 unmap_page_range+0x36f2/0x40f0 mm/memory.c:1795
 unmap_vmas+0x3cc/0x5f0 mm/memory.c:1885
 exit_mmap+0x264/0xc80 mm/mmap.c:3341
 __mmput+0x115/0x3c0 kernel/fork.c:1346
 exit_mm+0x220/0x310 kernel/exit.c:565
 do_exit+0x9aa/0x27e0 kernel/exit.c:861
 do_group_exit+0x207/0x2c0 kernel/exit.c:1023
 get_signal+0x16a1/0x1740 kernel/signal.c:2909
 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0xc9/0x370 kernel/entry/common.c:218
 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe4c8f75d39
RSP: 002b:00007fe4c9c85048 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: 000000000000000b RBX: 00007fe4c9103fa0 RCX: 00007fe4c8f75d39
RDX: 0000000000000318 RSI: 00000000200bd000 RDI: 0000000000000005
RBP: 00007fe4c8ff6766 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fe4c9103fa0 R15: 00007ffd2ddb1e88
 </TASK>
rcu: rcu_preempt kthread starved for 10324 jiffies! g34833 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:25520 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5408 [inline]
 __schedule+0x17e8/0x4a20 kernel/sched/core.c:6745
 __schedule_loop kernel/sched/core.c:6822 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6837
 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2581
 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2000
 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2202
 kthread+0x2f2/0x390 kernel/kthread.c:389
 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.10.0-rc5-syzkaller-00018-g55027e689933 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline]
RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:72 [inline]
RIP: 0010:acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:113
Code: 90 90 90 90 90 90 90 90 90 65 48 8b 04 25 c0 d4 03 00 48 f7 00 08 00 00 00 75 10 eb 07 0f 00 2d 95 6c a3 00 f3 0f 1e fa fb f4 <fa> e9 d4 33 2a 00 66 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90
RSP: 0018:ffffffff8e007ca8 EFLAGS: 00000246
RAX: ffffffff8e094680 RBX: ffff8880176fb864 RCX: 00000000001015f1
RDX: 0000000000000001 RSI: ffff8880176fb800 RDI: ffff8880176fb864
RBP: 000000000003a578 R08: ffff8880b9437ccb R09: 1ffff11017286f99
R10: dffffc0000000000 R11: ffffffff8b8608e0 R12: ffff88801ab95000
R13: 0000000000000000 R14: 0000000000000001 R15: ffffffff8eacdd00
FS:  0000000000000000(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fffc8858ff8 CR3: 000000007ddf0000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 acpi_idle_enter+0xe4/0x140 drivers/acpi/processor_idle.c:707
 cpuidle_enter_state+0x114/0x480 drivers/cpuidle/cpuidle.c:267
 cpuidle_enter+0x5d/0xa0 drivers/cpuidle/cpuidle.c:388
 call_cpuidle kernel/sched/idle.c:155 [inline]
 cpuidle_idle_call kernel/sched/idle.c:236 [inline]
 do_idle+0x375/0x5d0 kernel/sched/idle.c:332
 cpu_startup_entry+0x42/0x60 kernel/sched/idle.c:430
 rest_init+0x2dc/0x300 init/main.c:747
 start_kernel+0x47a/0x500 init/main.c:1103
 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:507
 x86_64_start_kernel+0x99/0xa0 arch/x86/kernel/head64.c:488
 common_startup_64+0x13e/0x147
 </TASK>

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/25 14:50 upstream 55027e689933 215eef4a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in ext4_release_file
2024/05/26 03:10 upstream 56fb6f92854f a10a183e .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_release_file
2024/03/04 08:14 upstream 58c806d867bf 25905f5d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in ext4_release_file
* Struck through repros no longer work on HEAD.