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INFO: rcu detected stall in sys_mount

Status: upstream: reported on 2024/12/14 21:36
Reported-by: syzbot+4e7d075998b1d352e3bf@syzkaller.appspotmail.com
First crash: 7d04h, last: 7d04h
▶ ▼ Similar bugs (9)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_mount (6) ntfs C inconclusive 82 407d 1181d 0/28 auto-obsoleted due to no activity on 2024/02/18 04:52
upstream INFO: rcu detected stall in sys_mount (4) fs 2 1753d 1768d 0/28 auto-closed as invalid on 2020/06/02 15:48
upstream INFO: rcu detected stall in sys_mount (5) afs C done done 10 1543d 1564d 15/28 fixed on 2020/11/16 12:12
linux-5.15 INFO: rcu detected stall in sys_mount 2 9d05h 71d 0/3 upstream: reported on 2024/10/11 22:21
upstream INFO: rcu detected stall in sys_mount (3) kernel 6 1844d 1845d 0/28 closed as invalid on 2019/12/04 14:04
upstream INFO: rcu detected stall in sys_mount nfs 1 2250d 2250d 0/28 closed as invalid on 2018/10/29 13:47
upstream INFO: rcu detected stall in sys_mount (7) fs C inconclusive done 40 11d 239d 0/28 upstream: reported C repro on 2024/04/26 05:48
upstream INFO: rcu detected stall in sys_mount (2) exfat 1 2201d 2201d 0/28 closed as dup on 2018/12/12 21:01
android-5-15 BUG: soft lockup in sys_mount origin:lts C error 17 170d 247d 0/2 auto-obsoleted due to no activity on 2024/10/17 05:03

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (0 ticks this GP) idle=c8dc/1/0x4000000000000000 softirq=18914/18914 fqs=26
	(detected by 0, t=10502 jiffies, g=21757, q=508 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 6028 Comm: syz.4.570 Tainted: G        W          6.1.120-syzkaller-00773-g52f863f820fd #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:__lock_release kernel/locking/lockdep.c:5316 [inline]
RIP: 0010:lock_release+0x1a5/0xa20 kernel/locking/lockdep.c:5682
Code: 80 3c 3b 00 74 08 4c 89 f7 e8 f7 5c 77 00 4c 8b ac 24 b0 00 00 00 fa 48 c7 c7 40 10 0c 8b e8 b2 84 47 09 65 ff 05 bb af 97 7e <48> 8d 9c 24 80 00 00 00 48 c1 eb 03 42 0f b6 04 3b 84 c0 0f 85 6e
RSP: 0018:ffffc900001e0b60 EFLAGS: 00000002
RAX: 0000000000000001 RBX: 1ffff9200003c182 RCX: ffffffff816ac827
RDX: 0000000000000000 RSI: ffffffff8b0c1040 RDI: ffffffff8b5e6500
RBP: ffffc900001e0ca0 R08: dffffc0000000000 R09: fffffbfff1d360c6
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200003c178
R13: 0000000000000046 R14: ffffc900001e0c10 R15: dffffc0000000000
FS:  00007fe3583eb6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f149e6faf98 CR3: 000000007a940000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 __raw_spin_unlock include/linux/spinlock_api_smp.h:141 [inline]
 _raw_spin_unlock+0x12/0x40 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 advance_sched+0x68b/0x970 net/sched/sch_taprio.c:749
 __run_hrtimer kernel/time/hrtimer.c:1689 [inline]
 __hrtimer_run_queues+0x5e5/0xe50 kernel/time/hrtimer.c:1753
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1815
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
 __sysvec_apic_timer_interrupt+0x158/0x5b0 arch/x86/kernel/apic/apic.c:1124
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xd4/0x130 kernel/locking/spinlock.c:194
Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 b2 87 25 f7 f6 44 24 21 02 75 4e 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> 37 f1 a1 f6 65 8b 05 f8 d0 45 75 85 c0 74 3f 48 c7 04 24 0e 36
RSP: 0018:ffffc90003a8f100 EFLAGS: 00000206
RAX: 701e8ffecc506b00 RBX: 1ffff92000751e24 RCX: ffffffff816b123a
RDX: dffffc0000000000 RSI: ffffffff8b0c0360 RDI: 0000000000000001
RBP: ffffc90003a8f190 R08: dffffc0000000000 R09: fffffbfff2249c60
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffff92000751e20 R14: ffffc90003a8f120 R15: 0000000000000246
 rcu_report_exp_rnp kernel/rcu/tree_exp.h:224 [inline]
 rcu_preempt_deferred_qs_irqrestore+0x894/0xc50 kernel/rcu/tree_plugin.h:567
 rcu_read_unlock_special+0x467/0x540 kernel/rcu/tree_plugin.h:681
 __rcu_read_unlock+0x92/0x100 kernel/rcu/tree_plugin.h:426
 rcu_read_unlock include/linux/rcupdate.h:823 [inline]
 is_bpf_text_address+0x27a/0x2a0 kernel/bpf/core.c:733
 kernel_text_address+0x9f/0xd0 kernel/extable.c:125
 __kernel_text_address+0x9/0x40 kernel/extable.c:79
 unwind_get_return_address+0x49/0x80 arch/x86/kernel/unwind_orc.c:323
 arch_stack_walk+0xf3/0x140 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 __kasan_kmalloc+0x97/0xb0 mm/kasan/common.c:383
 kasan_kmalloc include/linux/kasan.h:211 [inline]
 __do_kmalloc_node mm/slab_common.c:936 [inline]
 __kmalloc+0xb2/0x230 mm/slab_common.c:949
 kmalloc include/linux/slab.h:568 [inline]
 kzalloc include/linux/slab.h:699 [inline]
 __prealloc_shrinker+0x10f/0x7c0 mm/vmscan.c:641
 __register_shrinker mm/vmscan.c:703 [inline]
 register_shrinker+0x1a/0x120 mm/vmscan.c:733
 ext4_es_register_shrinker+0x268/0x2e0 fs/ext4/extents_status.c:1736
 __ext4_fill_super fs/ext4/super.c:5236 [inline]
 ext4_fill_super+0x5496/0x8b50 fs/ext4/super.c:5653
 get_tree_bdev+0x3fe/0x620 fs/super.c:1366
 vfs_get_tree+0x88/0x270 fs/super.c:1573
 do_new_mount+0x2ba/0xb40 fs/namespace.c:3056
 do_mount fs/namespace.c:3399 [inline]
 __do_sys_mount fs/namespace.c:3607 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3584
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fe3575874ba
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe3583eae68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fe3583eaef0 RCX: 00007fe3575874ba
RDX: 0000000020000080 RSI: 0000000020000480 RDI: 00007fe3583eaeb0
RBP: 0000000020000080 R08: 00007fe3583eaef0 R09: 0000000000000010
R10: 0000000000000010 R11: 0000000000000246 R12: 0000000020000480
R13: 00007fe3583eaeb0 R14: 0000000000000468 R15: 0000000020000140
 </TASK>
rcu: rcu_preempt kthread starved for 10450 jiffies! g21757 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:26136 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 PID: 6013 Comm: syz.0.565 Tainted: G        W          6.1.120-syzkaller-00773-g52f863f820fd #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:csd_lock_wait kernel/smp.c:424 [inline]
RIP: 0010:smp_call_function_many_cond+0x1fae/0x3460 kernel/smp.c:998
Code: 2f 44 89 ee 83 e6 01 31 ff e8 0e 44 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 0a e8 99 40 0b 00 e9 1b ff ff ff f3 90 <42> 0f b6 04 2b 84 c0 75 14 41 f7 07 01 00 00 00 0f 84 fe fe ff ff
RSP: 0018:ffffc90003ea7300 EFLAGS: 00000246
RAX: ffffffff817f5bf9 RBX: 1ffff110171e81b1 RCX: 0000000000080000
RDX: ffffc9000c699000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc90003ea76e0 R08: ffffffff817f5bc2 R09: fffffbfff2249c75
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000800000000
R13: dffffc0000000000 R14: 0000000000000001 R15: ffff8880b8f40d88
FS:  00007f42f2bfc6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f42f1d69160 CR3: 000000002688c000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1166
 invalidate_bdev+0x8a/0xb0 block/bdev.c:85
 btrfs_get_bdev_and_sb+0x109/0x190 fs/btrfs/volumes.c:518
 btrfs_open_one_device fs/btrfs/volumes.c:611 [inline]
 open_fs_devices+0x28c/0x1180 fs/btrfs/volumes.c:1280
 btrfs_mount_root+0x531/0x930 fs/btrfs/super.c:1807
 legacy_get_tree+0xeb/0x180 fs/fs_context.c:632
 vfs_get_tree+0x88/0x270 fs/super.c:1573
 fc_mount fs/namespace.c:1043 [inline]
 vfs_kern_mount+0xb8/0x150 fs/namespace.c:1073
 btrfs_mount+0x39b/0xb40 fs/btrfs/super.c:1895
 legacy_get_tree+0xeb/0x180 fs/fs_context.c:632
 vfs_get_tree+0x88/0x270 fs/super.c:1573
 do_new_mount+0x2ba/0xb40 fs/namespace.c:3056
 do_mount fs/namespace.c:3399 [inline]
 __do_sys_mount fs/namespace.c:3607 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3584
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f42f1d874ba
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f42f2bfbe68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f42f2bfbef0 RCX: 00007f42f1d874ba
RDX: 0000000020005100 RSI: 0000000020005140 RDI: 00007f42f2bfbeb0
RBP: 0000000020005100 R08: 00007f42f2bfbef0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000020005140
R13: 00007f42f2bfbeb0 R14: 0000000000005109 R15: 0000000020005180
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/12/14 21:35 linux-6.1.y 52f863f820fd 7cbfbb3a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_mount
* Struck through repros no longer work on HEAD.