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INFO: rcu detected stall in ext4_file_mmap (4)

Status: auto-obsoleted due to no activity on 2025/09/24 08:09
Subsystems: ext4
[Documentation on labels]
First crash: 106d, last: 106d
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in ext4_file_mmap ext4 1 1 1379d 1379d 0/29 closed as invalid on 2022/02/08 09:50
upstream INFO: rcu detected stall in ext4_file_mmap (2) ext4 1 1 1195d 1195d 0/29 auto-closed as invalid on 2022/10/01 04:43
upstream INFO: rcu detected stall in ext4_file_mmap (3) ext4 1 5 282d 470d 0/29 auto-obsoleted due to no activity on 2025/04/01 12:12
android-5-15 BUG: soft lockup in ext4_file_mmap 1 1 776d 776d 0/2 auto-obsoleted due to no activity on 2023/11/24 06:17

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 GPs behind) idle=e1ac/1/0x4000000000000000 softirq=51083/51084 fqs=14
rcu: 	(detected by 1, t=10502 jiffies, g=41421, q=1417 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 12024 Comm: modprobe Not tainted 6.16.0-rc3-syzkaller-00057-g92ca6c498a5e #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:arch_atomic_try_cmpxchg arch/x86/include/asm/atomic.h:107 [inline]
RIP: 0010:raw_atomic_try_cmpxchg_acquire include/linux/atomic/atomic-arch-fallback.h:2170 [inline]
RIP: 0010:atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:1302 [inline]
RIP: 0010:queued_spin_lock include/asm-generic/qspinlock.h:111 [inline]
RIP: 0010:do_raw_spin_lock+0x12e/0x290 kernel/locking/spinlock_debug.c:116
Code: 00 48 89 df be 04 00 00 00 e8 de e0 82 00 48 8d 7c 24 40 be 04 00 00 00 e8 cf e0 82 00 8b 44 24 40 b9 01 00 00 00 f0 0f b1 0b <0f> 85 dd 00 00 00 65 8b 1d 19 0a fb 10 48 b9 00 00 00 00 00 fc ff
RSP: 0018:ffffc90000007b20 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffffffff99c36010 RCX: 0000000000000001
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc90000007b60
RBP: ffffc90000007bd0 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000000f6c R12: ffffffff99c36020
R13: ffffffff99c36018 R14: 1ffffffff3386c04 R15: 1ffffffff3386c03
FS:  0000000000000000(0000) GS:ffff888125c83000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8fbc1124e8 CR3: 0000000029998000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline]
 _raw_spin_lock_irqsave+0xb3/0xf0 kernel/locking/spinlock.c:162
 debug_object_activate+0xbb/0x420 lib/debugobjects.c:818
 debug_hrtimer_activate kernel/time/hrtimer.c:445 [inline]
 debug_activate kernel/time/hrtimer.c:484 [inline]
 enqueue_hrtimer+0x30/0x3a0 kernel/time/hrtimer.c:1088
 __run_hrtimer kernel/time/hrtimer.c:1778 [inline]
 __hrtimer_run_queues+0x656/0xc60 kernel/time/hrtimer.c:1825
 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
 __sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1056
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1050
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xa8/0x110 kernel/locking/spinlock.c:194
Code: 74 05 e8 2b b3 65 f6 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4f f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> f3 9d 2e f6 65 8b 05 ec aa 37 07 85 c0 74 40 48 c7 04 24 0e 36
RSP: 0018:ffffc9001c71f020 EFLAGS: 00000206
RAX: 2ae865dc3c31ea00 RBX: 0000000000000a02 RCX: 2ae865dc3c31ea00
RDX: 0000000000000007 RSI: ffffffff8d96ea60 RDI: 0000000000000001
RBP: ffffc9001c71f0b8 R08: ffffffff8f9fe1f7 R09: 1ffffffff1f3fc3e
R10: dffffc0000000000 R11: fffffbfff1f3fc3f R12: dffffc0000000000
R13: 0000000000000000 R14: ffffffff8e8d0bf0 R15: 1ffff920038e3e04
 stack_depot_save_flags+0x429/0x900 lib/stackdepot.c:671
 kasan_save_stack mm/kasan/common.c:48 [inline]
 kasan_save_track+0x4f/0x80 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:319 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:345
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4148 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4204
 journal_alloc_journal_head fs/jbd2/journal.c:2826 [inline]
 jbd2_journal_add_journal_head+0x95/0x4b0 fs/jbd2/journal.c:2894
 jbd2_journal_get_write_access+0x1c9/0x230 fs/jbd2/transaction.c:1237
 __ext4_journal_get_write_access+0x1c3/0x570 fs/ext4/ext4_jbd2.c:242
 ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:6247
 __ext4_mark_inode_dirty+0x15b/0x700 fs/ext4/inode.c:6422
 ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6459
 __mark_inode_dirty+0x2d1/0xdf0 fs/fs-writeback.c:2527
 generic_update_time fs/inode.c:2064 [inline]
 inode_update_time fs/inode.c:2077 [inline]
 touch_atime+0x59b/0x6d0 fs/inode.c:2149
 file_accessed include/linux/fs.h:2652 [inline]
 ext4_file_mmap+0x244/0x5d0 fs/ext4/file.c:827
 call_mmap include/linux/fs.h:2286 [inline]
 mmap_file mm/internal.h:167 [inline]
 __mmap_new_file_vma mm/vma.c:2405 [inline]
 __mmap_new_vma mm/vma.c:2467 [inline]
 __mmap_region mm/vma.c:2622 [inline]
 mmap_region+0x127a/0x1f30 mm/vma.c:2692
 do_mmap+0xc45/0x10d0 mm/mmap.c:561
 vm_mmap_pgoff+0x31b/0x4c0 mm/util.c:579
 ksys_mmap_pgoff+0x51f/0x760 mm/mmap.c:607
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8fbc143242
Code: 08 00 04 00 00 eb e2 90 41 f7 c1 ff 0f 00 00 75 27 55 89 cd 53 48 89 fb 48 85 ff 74 33 41 89 ea 48 89 df b8 09 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 5e 5b 5d c3 0f 1f 00 c7 05 46 40 01 00 16 00
RSP: 002b:00007fff70395318 EFLAGS: 00000206 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f8fbc042000 RCX: 00007f8fbc143242
RDX: 0000000000000003 RSI: 0000000000006000 RDI: 00007f8fbc042000
RBP: 0000000000000812 R08: 0000000000000000 R09: 00000000001cc000
R10: 0000000000000812 R11: 0000000000000206 R12: 00007fff703953d8
R13: 00007f8fbc1175f0 R14: 00007fff70395b50 R15: 00000fffee072a66
 </TASK>
rcu: rcu_preempt kthread starved for 10474 jiffies! g41421 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:26464 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5396 [inline]
 __schedule+0x16a2/0x4cb0 kernel/sched/core.c:6785
 __schedule_loop kernel/sched/core.c:6863 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6878
 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 2937 Comm: kworker/u8:7 Not tainted 6.16.0-rc3-syzkaller-00057-g92ca6c498a5e #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0xf69/0x12d0 kernel/smp.c:885
Code: 00 45 8b 2f 44 89 ee 83 e6 01 31 ff e8 60 78 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 0b 74 0b 00 eb 37 f3 90 <43> 0f b6 04 2c 84 c0 75 10 41 f7 07 01 00 00 00 74 1e e8 f0 73 0b
RSP: 0018:ffffc9000bce76a0 EFLAGS: 00000293
RAX: ffffffff81b4d830 RBX: ffff8880b873b040 RCX: ffff88802f9e1e00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000bce7800 R08: ffffffff8f9fe1f7 R09: 1ffffffff1f3fc3e
R10: dffffc0000000000 R11: fffffbfff1f3fc3f R12: 1ffff110170c835d
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8880b8641ae8
FS:  0000000000000000(0000) GS:ffff888125d83000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1479f81178 CR3: 000000000df38000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052
 on_each_cpu include/linux/smp.h:71 [inline]
 smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2691 [inline]
 smp_text_poke_batch_finish+0x5e0/0x1100 arch/x86/kernel/alternative.c:2901
 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
 static_key_enable_cpuslocked+0x128/0x250 kernel/jump_label.c:210
 static_key_enable+0x1a/0x20 kernel/jump_label.c:223
 toggle_allocation_gate+0xad/0x240 mm/kfence/core.c:850
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3321
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/06/26 08:06 upstream 92ca6c498a5e 26d77996 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in ext4_file_mmap
* Struck through repros no longer work on HEAD.