[syzbot] [fs?] WARNING in schedstat_start

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    fe15c26ee26e Linux 6.3-rc1
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
console output: https://syzkaller.appspot.com/x/log.txt?x=17eda014c80000
kernel config:  https://syzkaller.appspot.com/x/.config?x=7573cbcd881a88c9
dashboard link: https://syzkaller.appspot.com/bug?extid=184ec1dbe951014904b3
compiler:       Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2
userspace arch: arm64
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=12ef5932c80000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=16981670c80000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/89d41abd07bd/disk-fe15c26e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/fa75f5030ade/vmlinux-fe15c26e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/590d0f5903ee/Image-fe15c26e.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+184ec1dbe951014904b3@xxxxxxxxxxxxxxxxxxxxxxxxx

------------[ cut here ]------------
WARNING: CPU: 0 PID: 5944 at include/linux/cpumask.h:143 schedstat_start+0x1a0/0x20c kernel/sched/stats.c:206
Modules linked in:
CPU: 0 PID: 5944 Comm: syz-executor219 Not tainted 6.3.0-rc1-syzkaller-gfe15c26ee26e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : cpu_max_bits_warn kernel/sched/stats.c:206 [inline]
pc : cpumask_check include/linux/cpumask.h:150 [inline]
pc : cpumask_next include/linux/cpumask.h:212 [inline]
pc : schedstat_start+0x1a0/0x20c kernel/sched/stats.c:196
lr : seq_read_iter+0x378/0xc44 fs/seq_file.c:225
sp : ffff80001e4e7980
x29: ffff80001e4e7990 x28: ffff0000d49ea1f0 x27: 1fffe0001a93d43e
x26: ffff0000d49ea140 x25: dfff800000000000 x24: 0000000000000007
x23: ffff800015cdd558 x22: 1fffe0001a93d42a x21: dfff800000000000
x20: ffff800015cdd000 x19: ffff0000d49ea150 x18: 0000000000000000
x17: 0000000000000000 x16: ffff80000826e470 x15: 0000000000000000
x14: 1ffff00002b9c0b2 x13: dfff800000000000 x12: 0000000000000001
x11: 1ffff00002b9baab x10: 0000000000000002 x9 : ffff800008af6624
x8 : 0000000000000009 x7 : ffff800008af63c8 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000001 x3 : ffff80000830ba14
x2 : ffff0000d14c1b40 x1 : ffff0000d49ea150 x0 : ffff0000d49ea128
Call trace:
 schedstat_start+0x1a0/0x20c kernel/sched/stats.c:206
 seq_read_iter+0x378/0xc44 fs/seq_file.c:225
 proc_reg_read_iter+0x18c/0x2bc fs/proc/inode.c:305
 call_read_iter include/linux/fs.h:1845 [inline]
 new_sync_read fs/read_write.c:389 [inline]
 vfs_read+0x5bc/0x8ac fs/read_write.c:470
 ksys_read+0x15c/0x26c fs/read_write.c:613
 __do_sys_read fs/read_write.c:623 [inline]
 __se_sys_read fs/read_write.c:621 [inline]
 __arm64_sys_read+0x7c/0x90 fs/read_write.c:621
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x64/0x198 arch/arm64/kernel/syscall.c:193
 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:591
irq event stamp: 11872
hardirqs last  enabled at (11871): [<ffff800008064fd4>] local_daif_restore arch/arm64/include/asm/daifflags.h:75 [inline]
hardirqs last  enabled at (11871): [<ffff800008064fd4>] el0_svc_common+0x9c/0x258 arch/arm64/kernel/syscall.c:107
hardirqs last disabled at (11872): [<ffff80001245e098>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:405
softirqs last  enabled at (11864): [<ffff800008020ec0>] softirq_handle_end kernel/softirq.c:414 [inline]
softirqs last  enabled at (11864): [<ffff800008020ec0>] __do_softirq+0xd64/0xfbc kernel/softirq.c:600
softirqs last disabled at (11859): [<ffff80000802b524>] ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:80
---[ end trace 0000000000000000 ]---


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