kernel: protection fault trap, code=NUM

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: afd4d70f932f Implement __builtin_clear_cache() on riscv64
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=11d40ef3300000
kernel config: https://syzkaller.appspot.com/x/.config?x=bf87b6915a88cd0d
dashboard link: https://syzkaller.appspot.com/bug?extid=a07dbe976a1d62ecc324

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

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+a07dbe...@syzkaller.appspotmail.com

kernel: protection fault trap, code=0
Stopped at sched_choosecpu+0x222: movl 0x20(%rbx),%ecx
ddb{0}>
ddb{0}> SeaBIOS (version 1.8.2-google)
Total RAM Size = 0x0000000080000000 = 2048 MiB
CPUs found: 2 Max CPUs supported: 2
SeaBIOS (version 1.8.2-google)
Machine UUID 003a59b7-54eb-38ca-1cfb-72bc238e03e5
found virtio-scsi at 0:3
virtio-scsi vendor='Google' product='PersistentDisk' rev='1' type=0 removable=0
virtio-scsi blksize=512 sectors=4194304 = 2048 MiB
drive 0x000f2430: PCHS=0/0/0 translation=lba LCHS=520/128/63 s=4194304
Sending Seabios boot VM event.
Booting from Hard Disk 0...
>> OpenBSD/amd64 BOOT 3.53
boot> set $lines = 0
set: syntax error
boot> set $maxwidth = 0
set: syntax error
boot> show panic
boot: illegal argument panic
boot> trace
boot> show registers
boot> show proc
boot> ps
boot> show all locks
boot> show malloc
boot> show all pools
boot> machine ddbcpu 0
machine: syntax error
boot> trace
boot> machine ddbcpu 1
machine: syntax error
boot> trace


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

[Anton Lindqvist]

#syz invalid