[syzbot] [kernel?] WARNING in kcov_task_exit

[syzbot <syzbot+47cf95ca1f9dcca872c8@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    cbf33b8e0b36 Merge tag 'bpf-fixes' of git://git.kernel.org..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=10440ee2580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=d4754d79c625c476
dashboard link: https://syzkaller.appspot.com/bug?extid=47cf95ca1f9dcca872c8
compiler:       Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/f8dd21bcf666/disk-cbf33b8e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/190c622f8270/vmlinux-cbf33b8e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/95c5beb798e9/bzImage-cbf33b8e.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+47cf95ca1f9dcca872c8@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 1 PID: 11596 at kernel/kcov.c:477 kcov_task_exit+0x13c/0x150 kernel/kcov.c:477
Modules linked in:
CPU: 1 UID: 0 PID: 11596 Comm: syz.4.1726 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:kcov_task_exit+0x13c/0x150 kernel/kcov.c:477
Code: c7 c7 40 98 a4 8e 48 c7 c6 3c c6 ba 8c 48 c7 c2 fa 9c b9 8c 4c 89 f9 e8 32 46 f0 02 4c 39 bb 98 00 00 00 0f 84 ff fe ff ff 90 <0f> 0b 90 4c 89 f7 5b 41 5e 41 5f e9 f4 9f f7 08 0f 1f 40 00 90 90
RSP: 0018:ffffc900055ffd00 EFLAGS: 00010287
RAX: f6d69a1b07268900 RBX: ffff88814131d800 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8b1dc0c0 RDI: 00000000ffffffff
RBP: ffffc900055ffe78 R08: 0000000000000000 R09: ffffffff8ab4d7a1
R10: dffffc0000000000 R11: fffffbfff1d6b527 R12: 1ffff11004c9279d
R13: 0000000000000000 R14: ffff88814131d808 R15: ffff888036835a00
FS:  000055557c98c500(0000) GS:ffff88812712f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005562f7e5e000 CR3: 00000000685d0000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 do_exit+0x105/0x2300 kernel/exit.c:905
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1107
 __do_sys_exit_group kernel/exit.c:1118 [inline]
 __se_sys_exit_group kernel/exit.c:1116 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1116
 x64_sys_call+0x21f7/0x2200 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f57eb2feec9
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffee660d918 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f57eb2feec9
RDX: 00007f57ea569000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffee660d97c R08: 00000000000123ac R09: 00000000000927c0
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000012a
R13: 00000000000927c0 R14: 000000000009ff7c R15: 00007ffee660d9d0
 </TASK>


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