[syzbot] upstream boot error: BUG: unable to handle kernel NULL pointer dereference in update_sd_lb_stats

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: ac9a78681b92 Linux 6.4-rc1
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1160fb12280000
kernel config: https://syzkaller.appspot.com/x/.config?x=cc86fee67199911d
dashboard link: https://syzkaller.appspot.com/bug?extid=cfb5d190e457dc724e57
compiler: arm-linux-gnueabi-gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
userspace arch: arm

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/c35b5b2731d2/non_bootable_disk-ac9a7868.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/c04bec59d77d/vmlinux-ac9a7868.xz
kernel image: https://storage.googleapis.com/syzbot-assets/070113b307f3/zImage-ac9a7868.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+cfb5d1...@syzkaller.appspotmail.com

8<--- cut here ---
Unable to handle kernel NULL pointer dereference at virtual address 00000004 when read
[00000004] *pgd=80000080004003, *pmd=00000000
Internal error: Oops: 206 [#1] PREEMPT SMP ARM
Modules linked in:
CPU: 1 PID: 15 Comm: rcu_preempt Not tainted 6.4.0-rc1-syzkaller #0
Hardware name: ARM-Versatile Express
PC is at update_sd_lb_stats.constprop.0+0/0
LR is at update_sd_lb_stats.constprop.0+0/0
pc : [<8028aa74>] lr : [<8028a8ec>] psr: a0000193
sp : df855ba8 ip : df855c0c fp : df855c3c
r10: ffff8e76 r9 : df855d34 r8 : 830b4640
r7 : 8309a800 r6 : ddddb400 r5 : df855bdc r4 : 00000000
r3 : 00000000 r2 : fffffff0 r1 : 00000000 r0 : df855bdc
Flags: NzCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment none
Control: 30c5387d Table: 80003000 DAC: 00000000
Register r0 information: non-paged memory
Register r1 information:
8<--- cut here ---
Unable to handle kernel NULL pointer dereference at virtual address 000001ff when read
[000001ff] *pgd=80000080004003, *pmd=00000000
Internal error: Oops: 206 [#2] PREEMPT SMP ARM
Modules linked in:


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[syzbot]

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