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INFO: rcu detected stall in ext4_file_mmap (2)

Status: auto-closed as invalid on 2022/10/01 04:43
Subsystems: ext4
[Documentation on labels]
First crash: 660d, last: 660d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in ext4_file_mmap ext4 1 844d 844d 0/26 closed as invalid on 2022/02/08 09:50
android-5-15 BUG: soft lockup in ext4_file_mmap 1 241d 241d 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:
	(detected by 0, t=10502 jiffies, g=121217, q=121 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4295056974-4295046472), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10502 jiffies! g121217 f0x2 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:28864 pid:   16 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5146 [inline]
 __schedule+0xa00/0x4b50 kernel/sched/core.c:6458
 schedule+0xd2/0x1f0 kernel/sched/core.c:6530
 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1935
 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1999
 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2187
 kthread+0x2e9/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 23527 Comm: sed Not tainted 5.19.0-rc4-syzkaller-00205-g34074da5424c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/29/2022
RIP: 0010:debug_object_activate+0xa1/0x3e0 lib/debugobjects.c:649
Code: 48 89 7c 24 58 48 c7 44 24 50 00 00 00 00 48 c7 44 24 40 00 00 00 00 48 c7 44 24 48 00 00 00 00 85 c0 c7 44 24 50 05 00 00 00 <48> 89 74 24 60 75 45 48 ba 00 00 00 00 00 fc ff df 49 01 d6 49 c7
RSP: 0018:ffffc900003f8d28 EFLAGS: 00000002
RAX: 0000000000000001 RBX: ffff8880b9b2a600 RCX: 0000000000000000
RDX: ffff88803357e040 RSI: ffffffff89cec240 RDI: ffff88803ed1fb40
RBP: ffff88803ed1fb40 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
R13: dffffc0000000000 R14: 1ffff9200007f1a7 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa4f4dda1d0 CR3: 000000003575e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 debug_hrtimer_activate kernel/time/hrtimer.c:420 [inline]
 debug_activate kernel/time/hrtimer.c:475 [inline]
 enqueue_hrtimer+0x27/0x3e0 kernel/time/hrtimer.c:1084
 __run_hrtimer kernel/time/hrtimer.c:1702 [inline]
 __hrtimer_run_queues+0xb02/0xe50 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline]
 __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1112
 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1106
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1b/0x20 arch/x86/include/asm/idtentry.h:649
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x38/0x70 kernel/locking/spinlock.c:194
Code: 74 24 10 e8 6a 6c e3 f7 48 89 ef e8 72 ed e3 f7 81 e3 00 02 00 00 75 25 9c 58 f6 c4 02 75 2d 48 85 db 74 01 fb bf 01 00 00 00 <e8> 13 f6 d6 f7 65 8b 05 ac 5e 88 76 85 c0 74 0a 5b 5d c3 e8 60 d5
RSP: 0018:ffffc90003b6f5b0 EFLAGS: 00000206
RAX: 0000000000000002 RBX: 0000000000000200 RCX: 1ffffffff20d75ae
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001
RBP: ffffffff8c6eef60 R08: 0000000000000001 R09: ffffffff9067b9af
R10: 0000000000000001 R11: 00000000000000af R12: 00000000000000b0
R13: 0000000000000202 R14: ffffc90003b6f638 R15: 0000000000000012
 __stack_depot_save+0x23f/0x500 lib/stackdepot.c:446
 kasan_save_stack+0x2e/0x40 mm/kasan/common.c:39
 kasan_set_track mm/kasan/common.c:45 [inline]
 set_alloc_info mm/kasan/common.c:436 [inline]
 __kasan_slab_alloc+0x85/0xb0 mm/kasan/common.c:469
 kasan_slab_alloc include/linux/kasan.h:224 [inline]
 slab_post_alloc_hook mm/slab.h:750 [inline]
 slab_alloc mm/slab.c:3302 [inline]
 __kmem_cache_alloc_lru mm/slab.c:3479 [inline]
 kmem_cache_alloc+0x265/0x560 mm/slab.c:3499
 kmem_cache_zalloc include/linux/slab.h:723 [inline]
 journal_alloc_journal_head fs/jbd2/journal.c:2861 [inline]
 jbd2_journal_add_journal_head+0x1cb/0x5c0 fs/jbd2/journal.c:2930
 jbd2_journal_get_write_access+0x112/0x190 fs/jbd2/transaction.c:1238
 __ext4_journal_get_write_access+0x1ba/0x440 fs/ext4/ext4_jbd2.c:235
 ext4_reserve_inode_write+0x187/0x270 fs/ext4/inode.c:5749
 __ext4_mark_inode_dirty+0x17b/0x8d0 fs/ext4/inode.c:5915
 ext4_dirty_inode+0xd4/0x110 fs/ext4/inode.c:5952
 __mark_inode_dirty+0x495/0x1050 fs/fs-writeback.c:2381
 generic_update_time fs/inode.c:1856 [inline]
 inode_update_time fs/inode.c:1869 [inline]
 touch_atime+0x63d/0x700 fs/inode.c:1941
 file_accessed include/linux/fs.h:2386 [inline]
 ext4_file_mmap+0x392/0x450 fs/ext4/file.c:780
 call_mmap include/linux/fs.h:2063 [inline]
 mmap_region+0xbe7/0x1460 mm/mmap.c:1796
 do_mmap+0x863/0xfa0 mm/mmap.c:1587
 vm_mmap_pgoff+0x1b7/0x290 mm/util.c:552
 ksys_mmap_pgoff+0x40d/0x5a0 mm/mmap.c:1633
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x46/0xb0
RIP: 0033:0x7fa4f4dfb1f2
Code: 04 00 00 5b 5d 41 5c c3 41 f7 c1 ff 0f 00 00 75 27 55 48 89 fd 53 89 cb 48 85 ff 74 33 41 89 da 48 89 ef b8 09 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 56 5b 5d c3 0f 1f 00 c7 05 9e 1f 01 00 16 00
RSP: 002b:00007fff9b8b0458 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 0000000000000802 RCX: 00007fa4f4dfb1f2
RDX: 0000000000000001 RSI: 00000000000264d0 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000000
R10: 0000000000000802 R11: 0000000000000246 R12: 00007fff9b8b0470
R13: 0000000000000000 R14: 0000000000000001 R15: 00007fa4f4dd9f00
 </TASK>
----------------
Code disassembly (best guess):
   0:	48 89 7c 24 58       	mov    %rdi,0x58(%rsp)
   5:	48 c7 44 24 50 00 00 	movq   $0x0,0x50(%rsp)
   c:	00 00
   e:	48 c7 44 24 40 00 00 	movq   $0x0,0x40(%rsp)
  15:	00 00
  17:	48 c7 44 24 48 00 00 	movq   $0x0,0x48(%rsp)
  1e:	00 00
  20:	85 c0                	test   %eax,%eax
  22:	c7 44 24 50 05 00 00 	movl   $0x5,0x50(%rsp)
  29:	00
* 2a:	48 89 74 24 60       	mov    %rsi,0x60(%rsp) <-- trapping instruction
  2f:	75 45                	jne    0x76
  31:	48 ba 00 00 00 00 00 	movabs $0xdffffc0000000000,%rdx
  38:	fc ff df
  3b:	49 01 d6             	add    %rdx,%r14
  3e:	49                   	rex.WB
  3f:	c7                   	.byte 0xc7

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/07/03 04:40 upstream 34074da5424c 1434eec0 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in ext4_file_mmap
* Struck through repros no longer work on HEAD.