EXT4-fs (loop4): VFS: Can't find ext4 filesystem
------------[ cut here ]------------
WARNING: CPU: 0 PID: 28823 at kernel/events/core.c:1978 perf_group_attach+0x396/0x450 kernel/events/core.c:1978
Modules linked in:
CPU: 0 PID: 28823 Comm: syz-executor.7 Not tainted 5.10.60 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
RIP: 0010:perf_group_attach+0x396/0x450 kernel/events/core.c:1978
Code: 48 c1 e8 03 42 80 3c 20 00 75 5f 48 8b 5b 10 48 83 eb 10 48 39 dd 75 d4 5b 5d 41 5c 41 5d 41 5e e9 0f fd f2 ff e8 0a fd f2 ff <0f> 0b e9 b1 fd ff ff 48 c7 c7 3c 3b 47 85 e8 d7 ec 1d 00 e9 b9 fc
RSP: 0018:ffff88805712fcb8 EFLAGS: 00010012
RAX: 000000000000245c RBX: ffff8880574e5000 RCX: ffffc90008228000
RDX: 0000000000040000 RSI: ffffffff814c61a6 RDI: ffff8880574e5220
RBP: ffff888058edd000 R08: 0000000000000001 R09: 0000000000000003
R10: 0000000000000000 R11: 0000000000000001 R12: ffff888017bbfc00
R13: 0000000000000000 R14: ffff888017bbf808 R15: 0000000000000000
FS:  00007fd9709f5700(0000) GS:ffff88806ce00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000003298c58 CR3: 000000005704a000 CR4: 0000000000350ef0
Call Trace:
 add_event_to_ctx kernel/events/core.c:2673 [inline]
 perf_install_in_context+0x448/0x540 kernel/events/core.c:2948
 __do_sys_perf_event_open+0x1ce7/0x2c80 kernel/events/core.c:12066
 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x466609
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd9709f5188 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 0000000000466609
RDX: 0000000000000000 RSI: 0000000000000412 RDI: 0000000020001d80
RBP: 00000000004bfcb9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000004 R11: 0000000000000246 R12: 000000000056bf80
R13: 00007ffc1047449f R14: 00007fd9709f5300 R15: 0000000000022000
irq event stamp: 2612
hardirqs last  enabled at (2611): [<ffffffff810feb5d>] __send_ipi_mask+0x2fd/0x3c0 arch/x86/kernel/kvm.c:555
hardirqs last disabled at (2612): [<ffffffff83d9d1ce>] __raw_spin_lock_irq include/linux/spinlock_api_smp.h:126 [inline]
hardirqs last disabled at (2612): [<ffffffff83d9d1ce>] _raw_spin_lock_irq+0x3e/0x40 kernel/locking/spinlock.c:167
softirqs last  enabled at (2552): [<ffffffff83e00f92>] asm_call_irq_on_stack+0x12/0x20
softirqs last disabled at (2543): [<ffffffff83e00f92>] asm_call_irq_on_stack+0x12/0x20
---[ end trace 110247195d41ffa8 ]---

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