[fs?] WARNING in seq_read_iter

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 44889ba56cbb Merge tag 'net-6.3-rc2' of git://git.kernel.o..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=154905b8c80000
kernel config: https://syzkaller.appspot.com/x/.config?x=d677dcd743eef09
dashboard link: https://syzkaller.appspot.com/bug?extid=c92f8ec6edc988604b28
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
CC: [linux-...@vger.kernel.org linux-...@vger.kernel.org]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/b53b8f59ed19/disk-44889ba5.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/403e9d83e80c/vmlinux-44889ba5.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a6bcf466de63/bzImage-44889ba5.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c92f8e...@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 0 PID: 5064 at include/linux/cpumask.h:143 cpu_max_bits_warn include/linux/cpumask.h:143 [inline]
WARNING: CPU: 0 PID: 5064 at include/linux/cpumask.h:143 cpumask_check include/linux/cpumask.h:150 [inline]
WARNING: CPU: 0 PID: 5064 at include/linux/cpumask.h:143 cpumask_next include/linux/cpumask.h:212 [inline]
WARNING: CPU: 0 PID: 5064 at include/linux/cpumask.h:143 c_start+0x1da/0x250 arch/x86/kernel/cpu/proc.c:156
Modules linked in:
CPU: 0 PID: 5064 Comm: syz-fuzzer Not tainted 6.3.0-rc1-syzkaller-00106-g44889ba56cbb #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
Code: 49 11 8c e8 88 a9 51 00 4c 89 e0 5b 5d 41 5c 41 5d 41 5e c3 f3 48 0f bc db e8 72 a9 51 00 89 db e9 38 ff ff ff e8 66 a9 51 00 <0f> 0b e9 c1 fe ff ff 48 c7 c7 80 7f 77 8e e8 d3 49 a2 00 e9 67 ff
RSP: 0018:ffffc900030efc68 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 0000000000000007 RCX: 0000000000000000
RDX: ffff888023096240 RSI: ffffffff813279da RDI: 0000000000000004
RBP: ffffffff8e777f80 R08: 0000000000000004 R09: 0000000000000007
R10: 0000000000000002 R11: 0000000000000000 R12: ffff88807e1cbb10
R13: 0000000000000008 R14: 0000000000000002 R15: 0000000000000000
FS: 0000000001ec53d0(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000d9dd43 CR3: 000000007ab89000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
seq_read_iter+0x2ca/0x12d0 fs/seq_file.c:225
proc_reg_read_iter+0x115/0x2d0 fs/proc/inode.c:301
call_read_iter include/linux/fs.h:1845 [inline]
new_sync_read fs/read_write.c:389 [inline]
vfs_read+0x681/0x930 fs/read_write.c:470
ksys_read+0x12b/0x250 fs/read_write.c:613
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x403ace
Code: 48 89 6c 24 38 48 8d 6c 24 38 e8 0d 00 00 00 48 8b 6c 24 38 48 83 c4 40 c3 cc cc cc 49 89 f2 48 89 fa 48 89 ce 48 89 df 0f 05 <48> 3d 01 f0 ff ff 76 15 48 f7 d8 48 89 c1 48 c7 c0 ff ff ff ff 48
RSP: 002b:000000c000af5308 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000403ace
RDX: 0000000000001000 RSI: 000000c0004e0000 RDI: 0000000000000003
RBP: 000000c000af5348 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000000c000af5488
R13: 0000000000000000 R14: 000000c0000061a0 R15: 0000040000000000
</TASK>


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.