assert "map->limit == rtmap_limit" failed in ker

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 135881df8fe2 To work with bounce buffers, xen_bus_dmamap_s..
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=171f9b7a580000
kernel config: https://syzkaller.appspot.com/x/.config?x=7058272de1526588
dashboard link: https://syzkaller.appspot.com/bug?extid=d9d78e99fd12959fca93

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/e8ad7c482ce1/disk-135881df.raw.xz
bsd.gdb: https://storage.googleapis.com/syzbot-assets/4e442582f983/bsd-135881df.gdb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/2ba9a814b47a/kernel-135881df.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+d9d78e...@syzkaller.appspotmail.com

panic: kernel diagnostic assertion "map->limit == rtmap_limit" failed: file "/syzkaller/managers/multicore/ker


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