[v6.1] INFO: rcu detected stall in sys_mount

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 52f863f820fd Linux 6.1.120
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=121c3cdf980000
kernel config: https://syzkaller.appspot.com/x/.config?x=aaac18cfcaf804f1
dashboard link: https://syzkaller.appspot.com/bug?extid=4e7d075998b1d352e3bf
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/be96d4cf0e01/disk-52f863f8.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/6a60a590df68/vmlinux-52f863f8.xz
kernel image: https://storage.googleapis.com/syzbot-assets/961868165f31/bzImage-52f863f8.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+4e7d07...@syzkaller.appspotmail.com

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>


---
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: b6736e03756f Linux 6.1.136
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=16a470f4580000
kernel config: https://syzkaller.appspot.com/x/.config?x=1f31c8b4cdebec00
dashboard link: https://syzkaller.appspot.com/bug?extid=4e7d075998b1d352e3bf
compiler: Debian clang version 20.1.2 (++20250402124445+58df0ef89dd6-1~exp1~20250402004600.97), Debian LLD 20.1.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=116b38d4580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=11a470f4580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/562d684b3c71/disk-b6736e03.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/16bb24a1b82d/vmlinux-b6736e03.xz
kernel image: https://storage.googleapis.com/syzbot-assets/40b3e76f572a/bzImage-b6736e03.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+4e7d07...@syzkaller.appspotmail.com

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:

rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4260/1:b..l
(detected by 1, t=10503 jiffies, g=8785, q=76 ncpus=2)
task:syz-executor236 state:R running task stack:25920 pid:4260 ppid:4255 flags:0x00004002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10e9/0x40d0 kernel/sched/core.c:6561
preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873
irqentry_exit+0x63/0x70 kernel/entry/common.c:439
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:lock_acquire+0x20f/0x490 kernel/locking/lockdep.c:5666
Code: 00 9c 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 0f 85 f5 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 44 3d 00 00 00 00 00 66 43 c7 44 3d 09 00 00 43 c6 44 3d 0b
RSP: 0018:ffffc90003d67480 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 75c24ad516f25b00
RDX: 0000000000000000 RSI: ffffffff8a6c0f80 RDI: ffffffff8abf0da0
RBP: ffffc90003d67598 R08: dffffc0000000000 R09: fffffbfff2117049
R10: fffffbfff2117049 R11: 1ffffffff2117048 R12: 0000000000000001
R13: 1ffff920007ace9c R14: 0000000000000246 R15: dffffc0000000000
rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
rcu_read_lock include/linux/rcupdate.h:791 [inline]
is_bpf_text_address+0x43/0x2a0 kernel/bpf/core.c:735
kernel_text_address+0x9c/0xd0 kernel/extable.c:125
__kernel_text_address+0x9/0x30 kernel/extable.c:79
unwind_get_return_address+0x49/0x80 arch/x86/kernel/unwind_orc.c:323
arch_stack_walk+0xf2/0x140 arch/x86/kernel/stacktrace.c:26
stack_trace_save+0x98/0xe0 kernel/stacktrace.c:122

kasan_save_stack mm/kasan/common.c:45 [inline]
kasan_set_track+0x4b/0x70 mm/kasan/common.c:52

kasan_save_free_info+0x2d/0x50 mm/kasan/generic.c:516
____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236
kasan_slab_free include/linux/kasan.h:177 [inline]
slab_free_hook mm/slub.c:1724 [inline]
slab_free_freelist_hook+0x131/0x1a0 mm/slub.c:1750
slab_free mm/slub.c:3661 [inline]
kmem_cache_free+0xf7/0x290 mm/slub.c:3683
kern_path+0x3b/0x50 fs/namei.c:2608
tomoyo_mount_acl security/tomoyo/mount.c:136 [inline]
tomoyo_mount_permission+0x75f/0x940 security/tomoyo/mount.c:237
security_sb_mount+0x83/0xb0 security/security.c:993
path_mount+0xb8/0x1010 fs/namespace.c:3329
do_mount fs/namespace.c:3400 [inline]
__do_sys_mount fs/namespace.c:3608 [inline]
__se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3585
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fe9408efcea
RSP: 002b:00007fff699bc1f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fe9409460ae RCX: 00007fe9408efcea
RDX: 0000000000000000 RSI: 00007fe940946181 RDI: 00007fe940946192
RBP: 00007fe940946181 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000045001 R11: 0000000000000246 R12: 00007fe94094c33c
R13: 00007fe940946106 R14: 0000000000000001 R15: 0000000000000001
</TASK>
rcu: rcu_preempt kthread starved for 10557 jiffies! g8785 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:27840 pid:16 ppid:2 flags:0x00004000
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10e9/0x40d0 kernel/sched/core.c:6561
schedule+0xb9/0x180 kernel/sched/core.c:6637
schedule_timeout+0x15c/0x280 kernel/time/timer.c:1965
rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706
rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905
kthread+0x29d/0x330 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:

Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4280 Comm: syz-executor236 Not tainted 6.1.136-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
RIP: 0010:check_kcov_mode kernel/kcov.c:182 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x13/0x60 kernel/kcov.c:216
Code: 48 8b 3d 80 c0 7d 0c 48 89 de 5b e9 17 aa 50 00 00 00 cc cc 00 00 cc 48 8b 04 24 65 48 8b 0d 94 ab 81 7e 65 8b 15 95 ab 81 7e <81> e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 1c 16 00 00
RSP: 0018:ffffc90003e27ac8 EFLAGS: 00000046
RAX: ffffffff814ffb08 RBX: ffff88803022bb80 RCX: ffff88803022bb80
RDX: 0000000080000001 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: dffffc0000000000 R09: ffffed1006045771
R10: ffffed1006045771 R11: 1ffff11006045770 R12: dffffc0000000000
R13: 0000000000000000 R14: ffff88803022c0f0 R15: ffff88802969a908
FS: 0000555591a693c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 00007fe940945448 CR3: 00000000790e4000 CR4: 00000000003506f0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:

<TASK>
arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline]
freezing include/linux/freezer.h:36 [inline]
recalc_sigpending+0x158/0x1c0 kernel/signal.c:184
__set_task_blocked kernel/signal.c:3031 [inline]
__set_current_blocked+0x1f8/0x240 kernel/signal.c:3059
set_current_blocked kernel/signal.c:3044 [inline]
signal_delivered kernel/signal.c:2907 [inline]
signal_setup_done+0x28c/0x440 kernel/signal.c:2919
handle_signal arch/x86/kernel/signal.c:846 [inline]
arch_do_signal_or_restart+0xeba/0x1230 arch/x86/kernel/signal.c:873
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fe940914d90
Code: 83 c0 16 83 e0 f7 74 12 50 48 8d 3d 1a 2a 03 00 e8 d5 06 fb ff 0f 1f 44 00 00 c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 <83> ff 21 74 0b c3 66 2e 0f 1f 84 00 00 00 00 00 55 53 48 89 f3 48
RSP: 002b:00007fff699bba38 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000004
RDX: 00007fff699bba40 RSI: 00007fff699bbb70 RDI: 0000000000000021
RBP: 00007fe940977130 R08: 00007fe9408ae990 R09: 00007fe9408ae990
R10: 0000000000000000 R11: 0000000000000293 R12: 00007fe940979dc8
R13: 0000000000000000 R14: 00007fe940979de0 R15: 00007fe9408b9f80
</TASK>
sched: RT throttling activated


---
If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.