syzbot


INFO: rcu detected stall in ext4_file_mmap

Status: closed as invalid on 2022/02/08 09:50
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 336d, last: 336d
similar bugs (1):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in ext4_file_mmap (2) 1 153d 153d 0/24 auto-closed as invalid on 2022/10/01 04:43

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (2 ticks this GP) idle=3f1/1/0x4000000000000000 softirq=204150/204151 fqs=1427 
	(detected by 1, t=10502 jiffies, g=283093, q=1030)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 5922 Comm: modprobe Not tainted 5.16.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline]
RIP: 0010:rcu_lockdep_current_cpu_online+0x0/0x150 kernel/rcu/tree.c:1166
Code: 4c 8b 44 24 38 4c 8b 4c 24 30 4c 8b 54 24 28 48 8b 54 24 20 48 8b 44 24 18 e9 41 fe ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 90 <65> 8b 15 19 24 a0 7e 81 e2 00 00 f0 00 b8 01 00 00 00 75 0a 8b 15
RSP: 0018:ffffc90000007d48 EFLAGS: 00000002
RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff815bdc31
RDX: 0000000000000000 RSI: 0000000000010003 RDI: ffffffff8b55b8a0
RBP: 1ffff92000000fae R08: 0000000000000000 R09: ffffffff8d911d97
R10: fffffbfff1b223b2 R11: 0000000000000000 R12: 0000000000000001
R13: ffff8880b9c2a500 R14: ffff8880b9c2a400 R15: ffffffff875ef5f0
FS:  0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f97ed313000 CR3: 000000006ed40000 CR4: 00000000003506f0
DR0: 0080ffff00000000 DR1: 0080ffff00000000 DR2: 0080ffff00000000
DR3: 0080ffff00000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 rcu_read_lock_held_common kernel/rcu/update.c:112 [inline]
 rcu_read_lock_held_common kernel/rcu/update.c:102 [inline]
 rcu_read_lock_sched_held+0x25/0x70 kernel/rcu/update.c:123
 trace_lock_release include/trace/events/lock.h:58 [inline]
 lock_release+0x522/0x720 kernel/locking/lockdep.c:5648
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline]
 _raw_spin_unlock_irqrestore+0x16/0x70 kernel/locking/spinlock.c:194
 __run_hrtimer kernel/time/hrtimer.c:1681 [inline]
 __hrtimer_run_queues+0x51a/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:1086 [inline]
 __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103
 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:jhash2 include/linux/jhash.h:129 [inline]
RIP: 0010:hash_stack lib/stackdepot.c:180 [inline]
RIP: 0010:__stack_depot_save+0xb6/0x4f0 lib/stackdepot.c:329
Code: c2 0c 44 8b 4a f4 03 42 f8 41 29 d9 45 01 c1 41 89 d8 01 c3 41 c1 c0 04 45 31 c8 44 29 c0 41 89 c1 44 89 c0 41 01 d8 c1 c0 06 <44> 31 c8 29 c3 41 89 d9 89 c3 44 01 c0 c1 c3 08 44 31 cb 41 89 d9
RSP: 0018:ffffc90002da7810 EFLAGS: 00000203
RAX: 00000000b6a4f00b RBX: 00000000385b447e RCX: 0000000000000001
RDX: ffffc90002da78b0 RSI: 0000000000000d40 RDI: 0000000000000012
RBP: ffff888071ba3f00 R08: 000000006735d83e R09: 000000008adf51c6
R10: ffffffff8100741e R11: 000000000008808a R12: ffffc90002da7880
R13: 000000000000000f R14: 000000000000000f R15: ffff888071ba3ec8
 kasan_save_stack+0x38/0x50 mm/kasan/common.c:40
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 __kasan_slab_alloc+0x85/0xb0 mm/kasan/common.c:467
 kasan_slab_alloc include/linux/kasan.h:259 [inline]
 slab_post_alloc_hook mm/slab.h:519 [inline]
 slab_alloc mm/slab.c:3323 [inline]
 kmem_cache_alloc+0x265/0x560 mm/slab.c:3507
 kmem_cache_zalloc include/linux/slab.h:714 [inline]
 jbd2_alloc_handle include/linux/jbd2.h:1603 [inline]
 new_handle fs/jbd2/transaction.c:481 [inline]
 jbd2__journal_start+0x191/0x930 fs/jbd2/transaction.c:508
 __ext4_journal_start_sb+0x227/0x4a0 fs/ext4/ext4_jbd2.c:105
 __ext4_journal_start fs/ext4/ext4_jbd2.h:326 [inline]
 ext4_dirty_inode+0x9d/0x110 fs/ext4/inode.c:5916
 __mark_inode_dirty+0x45b/0xfe0 fs/fs-writeback.c:2399
 generic_update_time fs/inode.c:1782 [inline]
 inode_update_time fs/inode.c:1795 [inline]
 touch_atime+0x63d/0x700 fs/inode.c:1867
 file_accessed include/linux/fs.h:2505 [inline]
 ext4_file_mmap+0x398/0x460 fs/ext4/file.c:782
 call_mmap include/linux/fs.h:2167 [inline]
 mmap_region+0xd86/0x1630 mm/mmap.c:1786
 do_mmap+0x869/0xfb0 mm/mmap.c:1575
 vm_mmap_pgoff+0x1b7/0x290 mm/util.c:519
 ksys_mmap_pgoff+0x40d/0x5a0 mm/mmap.c:1623
 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+0x44/0xae
RIP: 0033:0x7f852b4e81f2
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:00007ffef5265b88 EFLAGS: 00000206 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 0000000000000812 RCX: 00007f852b4e81f2
RDX: 0000000000000003 RSI: 0000000000002000 RDI: 00007f852b1a3000
RBP: 00007f852b1a3000 R08: 0000000000000000 R09: 0000000000002000
R10: 0000000000000812 R11: 0000000000000206 R12: 00007ffef5265ba0
R13: 00007ffef5265c30 R14: 0000000000000003 R15: 00007f852b1a5000
 </TASK>
rcu: rcu_preempt kthread starved for 7645 jiffies! g283093 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:28608 pid:   14 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4972 [inline]
 __schedule+0xa9a/0x4900 kernel/sched/core.c:6253
 schedule+0xd2/0x260 kernel/sched/core.c:6326
 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881
 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1955
 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2128
 kthread+0x405/0x4f0 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 1
CPU: 1 PID: 5942 Comm: syz-executor.5 Not tainted 5.16.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_check_gp_kthread_starvation.cold+0x1fb/0x200 kernel/rcu/tree_stall.h:481
 print_other_cpu_stall kernel/rcu/tree_stall.h:586 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:729 [inline]
 rcu_pending kernel/rcu/tree.c:3878 [inline]
 rcu_sched_clock_irq+0x1f7c/0x2150 kernel/rcu/tree.c:2597
 update_process_times+0x16d/0x200 kernel/time/timer.c:1785
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226
 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1428
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x1c0/0xe50 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline]
 __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103
 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:csd_lock_wait kernel/smp.c:440 [inline]
RIP: 0010:smp_call_function_many_cond+0x452/0xc20 kernel/smp.c:969
Code: 0b 00 85 ed 74 4d 48 b8 00 00 00 00 00 fc ff df 4d 89 f4 4c 89 f5 49 c1 ec 03 83 e5 07 49 01 c4 83 c5 03 e8 60 78 0b 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 33 06 00 00 8b 43 08 31
RSP: 0018:ffffc90002e979e0 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffffe8ffffc0b640 RCX: 0000000000000000
RDX: ffff88805ab04080 RSI: ffffffff816b4fa0 RDI: 0000000000000003
RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000001
R10: ffffffff816b4fc6 R11: 0000000000000000 R12: fffff91ffff816c9
R13: 0000000000000000 R14: ffffe8ffffc0b648 R15: 0000000000000001
 on_each_cpu_cond_mask+0x56/0xa0 kernel/smp.c:1135
 __purge_vmap_area_lazy+0x1f6/0x1c50 mm/vmalloc.c:1687
 try_purge_vmap_area_lazy mm/vmalloc.c:1727 [inline]
 free_vmap_area_noflush+0xa57/0xd00 mm/vmalloc.c:1769
 free_unmap_vmap_area mm/vmalloc.c:1782 [inline]
 remove_vm_area+0x1ca/0x230 mm/vmalloc.c:2528
 vm_remove_mappings mm/vmalloc.c:2557 [inline]
 __vunmap+0x392/0xb70 mm/vmalloc.c:2622
 __vfree+0x3c/0xd0 mm/vmalloc.c:2680
 vfree+0x5a/0x90 mm/vmalloc.c:2711
 kcov_put kernel/kcov.c:411 [inline]
 kcov_put+0x26/0x40 kernel/kcov.c:407
 kcov_close+0xc/0x10 kernel/kcov.c:513
 __fput+0x286/0x9f0 fs/file_table.c:280
 task_work_run+0xdd/0x1a0 kernel/task_work.c:164
 exit_task_work include/linux/task_work.h:32 [inline]
 do_exit+0xc14/0x2b40 kernel/exit.c:832
 do_group_exit+0x125/0x310 kernel/exit.c:929
 __do_sys_exit_group kernel/exit.c:940 [inline]
 __se_sys_exit_group kernel/exit.c:938 [inline]
 __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:938
 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+0x44/0xae
RIP: 0033:0x7fd7b17c7e99
Code: Unable to access opcode bytes at RIP 0x7fd7b17c7e6f.
RSP: 002b:00007ffc6c516818 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 000000010badf00d RCX: 00007fd7b17c7e99
RDX: 00007fd7b177a973 RSI: 000000000000000c RDI: 0000000000000043
RBP: 00000000ffffffff R08: 000000000000001b R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000006
R13: 00007ffc6c516910 R14: 00007fd7b18db4d8 R15: 0000000000000006
 </TASK>
----------------
Code disassembly (best guess):
   0:	4c 8b 44 24 38       	mov    0x38(%rsp),%r8
   5:	4c 8b 4c 24 30       	mov    0x30(%rsp),%r9
   a:	4c 8b 54 24 28       	mov    0x28(%rsp),%r10
   f:	48 8b 54 24 20       	mov    0x20(%rsp),%rdx
  14:	48 8b 44 24 18       	mov    0x18(%rsp),%rax
  19:	e9 41 fe ff ff       	jmpq   0xfffffe5f
  1e:	66 66 2e 0f 1f 84 00 	data16 nopw %cs:0x0(%rax,%rax,1)
  25:	00 00 00 00
  29:	90                   	nop
* 2a:	65 8b 15 19 24 a0 7e 	mov    %gs:0x7ea02419(%rip),%edx        # 0x7ea0244a <-- trapping instruction
  31:	81 e2 00 00 f0 00    	and    $0xf00000,%edx
  37:	b8 01 00 00 00       	mov    $0x1,%eax
  3c:	75 0a                	jne    0x48
  3e:	8b                   	.byte 0x8b
  3f:	15                   	.byte 0x15

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-kasan-gce-selinux-root 2021/12/31 18:59 upstream 4f3d93c6eaff e1768e9c .config log report info INFO: rcu detected stall in ext4_file_mmap
* Struck through repros no longer work on HEAD.