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INFO: rcu detected stall in sys_mount

Status: upstream: reported on 2024/10/11 22:21
Reported-by: syzbot+47cee05a30e3c83d3d1f@syzkaller.appspotmail.com
First crash: 10d, last: 10d
▶ ▼ Similar bugs (8)
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 347d 1121d 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 1693d 1708d 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 1483d 1504d 15/28 fixed on 2020/11/16 12:12
upstream INFO: rcu detected stall in sys_mount (3) kernel 6 1784d 1785d 0/28 closed as invalid on 2019/12/04 14:04
upstream INFO: rcu detected stall in sys_mount nfs 1 2190d 2190d 0/28 closed as invalid on 2018/10/29 13:47
upstream INFO: rcu detected stall in sys_mount (7) fs C inconclusive 33 28d 179d 0/28 upstream: reported C repro on 2024/04/26 05:48
upstream INFO: rcu detected stall in sys_mount (2) exfat 1 2141d 2141d 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 110d 187d 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: 	0-...!: (1 GPs behind) idle=309/1/0x4000000000000000 softirq=16421/16422 fqs=49 
	(detected by 1, t=10502 jiffies, g=19465, q=1203)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 6319 Comm: syz.1.830 Not tainted 5.15.167-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4709 [inline]
RIP: 0010:__lock_acquire+0x826/0x1ff0 kernel/locking/lockdep.c:4962
Code: 0f b6 04 10 84 c0 0f 85 c4 00 00 00 8b 03 41 38 c7 41 0f b6 cf 41 89 c7 44 0f 42 f9 84 c0 44 0f 44 f9 49 ff c6 48 8b 44 24 40 <0f> b6 04 10 84 c0 0f 85 be 00 00 00 48 8b 44 24 30 48 63 00 48 83
RSP: 0018:ffffc90000007a00 EFLAGS: 00000006
RAX: 1ffff110033f4c85 RBX: ffffffff900ee938 RCX: 0000000000000002
RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffffffff907120c8
RBP: ffff888019fa64a0 R08: dffffc0000000000 R09: fffffbfff20e241a
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000002
R13: ffff888019fa64a0 R14: 0000000000000003 R15: 0000000000000002
FS:  00007f3276ad36c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558d9cf808 CR3: 000000005dbda000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
 debug_object_deactivate+0x63/0x380 lib/debugobjects.c:748
 debug_hrtimer_deactivate kernel/time/hrtimer.c:425 [inline]
 debug_deactivate+0x1b/0x1e0 kernel/time/hrtimer.c:481
 __run_hrtimer kernel/time/hrtimer.c:1656 [inline]
 __hrtimer_run_queues+0x31d/0xcf0 kernel/time/hrtimer.c:1752
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1814
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:load_free_nid_bitmap fs/f2fs/node.c:3193 [inline]
RIP: 0010:f2fs_build_node_manager+0x15fd/0x2050 fs/f2fs/node.c:3315
Code: 89 df e8 56 60 25 fe 48 8b 2c 24 48 01 ed 48 03 2b 48 89 e8 48 c1 e8 03 42 0f b6 04 38 84 c0 48 8b 5c 24 40 75 18 66 ff 45 00 <41> ff c4 44 3b 64 24 38 73 26 e8 04 96 db fd e9 a9 fd ff ff 89 e9
RSP: 0018:ffffc90002ea7928 EFLAGS: 00000202
RAX: 0000000000000000 RBX: ffff888078098158 RCX: ffffffff83a4c40f
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88802746c788
RBP: ffff88807cb289a6 R08: dffffc0000000000 R09: ffffed1004e8d8f2
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000017762
R13: ffff888078098000 R14: 000000000000005d R15: dffffc0000000000
 f2fs_fill_super+0x5858/0x8350 fs/f2fs/super.c:4231
 mount_bdev+0x2c9/0x3f0 fs/super.c:1398
 legacy_get_tree+0xeb/0x180 fs/fs_context.c:611
 vfs_get_tree+0x88/0x270 fs/super.c:1528
 do_new_mount+0x2ba/0xb40 fs/namespace.c:3005
 do_mount fs/namespace.c:3348 [inline]
 __do_sys_mount fs/namespace.c:3556 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3533
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f327865c79a
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:00007f3276ad2e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f3276ad2ef0 RCX: 00007f327865c79a
RDX: 0000000020000080 RSI: 00000000200000c0 RDI: 00007f3276ad2eb0
RBP: 0000000020000080 R08: 00007f3276ad2ef0 R09: 0000000000000008
R10: 0000000000000008 R11: 0000000000000246 R12: 00000000200000c0
R13: 00007f3276ad2eb0 R14: 0000000000005505 R15: 0000000020000480
 </TASK>
rcu: rcu_preempt kthread starved for 10396 jiffies! g19465 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:27064 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 1
CPU: 1 PID: 6358 Comm: syz.2.845 Not tainted 5.15.167-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_check_gp_kthread_starvation+0x1d2/0x240 kernel/rcu/tree_stall.h:487
 print_other_cpu_stall+0x137a/0x14d0 kernel/rcu/tree_stall.h:592
 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
 rcu_pending kernel/rcu/tree.c:3932 [inline]
 rcu_sched_clock_irq+0xa38/0x1150 kernel/rcu/tree.c:2619
 update_process_times+0x196/0x200 kernel/time/timer.c:1818
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1688 [inline]
 __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1752
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1814
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:csd_lock_wait kernel/smp.c:440 [inline]
RIP: 0010:smp_call_function_many_cond+0xa93/0xd90 kernel/smp.c:969
Code: 04 03 84 c0 0f 85 84 00 00 00 45 8b 7d 00 44 89 fe 83 e6 01 31 ff e8 8c cc 0b 00 41 83 e7 01 75 07 e8 21 c9 0b 00 eb 41 f3 90 <48> b8 00 00 00 00 00 fc ff df 0f b6 04 03 84 c0 75 11 41 f7 45 00
RSP: 0018:ffffc90002f27820 EFLAGS: 00000246
RAX: ffffffff81749174 RBX: 1ffff11017208541 RCX: 0000000000040000
RDX: ffffc90004c71000 RSI: 000000000003ffff RDI: 0000000000040000
RBP: ffffc90002f27960 R08: ffffffff81749144 R09: fffffbfff20e2450
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000
R13: ffff8880b9042a08 R14: ffff8880b913b380 R15: 0000000000000001
 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1135
 invalidate_bdev+0x8a/0xb0 block/bdev.c:86
 ntfs_loadlog_and_replay+0x338/0x530 fs/ntfs3/fsntfs.c:305
 ntfs_fill_super+0x23b6/0x4340 fs/ntfs3/super.c:1013
 get_tree_bdev+0x3fe/0x620 fs/super.c:1323
 vfs_get_tree+0x88/0x270 fs/super.c:1528
 do_new_mount+0x2ba/0xb40 fs/namespace.c:3005
 do_mount fs/namespace.c:3348 [inline]
 __do_sys_mount fs/namespace.c:3556 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3533
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fcdc273579a
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:00007fcdc0babe68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fcdc0babef0 RCX: 00007fcdc273579a
RDX: 00000000200000c0 RSI: 0000000020000000 RDI: 00007fcdc0babeb0
RBP: 00000000200000c0 R08: 00007fcdc0babef0 R09: 0000000001214010
R10: 0000000001214010 R11: 0000000000000246 R12: 0000000020000000
R13: 00007fcdc0babeb0 R14: 000000000001f252 R15: 0000000020000380
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/10/11 22:20 linux-5.15.y 3a5928702e71 084d8178 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_mount
* Struck through repros no longer work on HEAD.