panic: pmap_growkernel: no memory to grow kernel

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 62dd3c74 powerpc: Drop OPAL_HANDLE_HMI2 for now, to avoid ..
git tree: freebsd
console output: https://syzkaller.appspot.com/x/log.txt?x=137dd7cca00000
dashboard link: https://syzkaller.appspot.com/bug?extid=3ce299f73d5bbb5377ad

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

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+3ce299...@syzkaller.appspotmail.com

panic: pmap_growkernel: no memory to grow kernel
cpuid = 0
time = 122
KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0x47/frame
0xfffffe0030b08260
vpanic() at vpanic+0x1e0/frame 0xfffffe0030b082c0
panic() at panic+0x43/frame 0xfffffe0030b08320
pmap_growkernel() at pmap_growkernel+0x4b6/frame 0xfffffe0030b08360
vm_map_insert() at vm_map_insert+0x38c/frame 0xfffffe0030b08420
vm_map_find() at vm_map_find+0x9e1/frame 0xfffffe0030b08510
kva_import() at kva_import+0x5f/frame 0xfffffe0030b08560
vmem_xalloc() at vmem_xalloc+0x711/frame 0xfffffe0030b08650
vmem_alloc() at vmem_alloc+0xe3/frame 0xfffffe0030b086b0
kva_alloc() at kva_alloc+0x37/frame 0xfffffe0030b086e0
vm_thread_new() at vm_thread_new+0x132/frame 0xfffffe0030b08830
thread_alloc() at thread_alloc+0x4f/frame 0xfffffe0030b08860
fork1() at fork1+0x6ba/frame 0xfffffe0030b08920
sys_fork() at sys_fork+0x56/frame 0xfffffe0030b08980
amd64_syscall() at amd64_syscall+0x436/frame 0xfffffe0030b08ab0
fast_syscall_common() at fast_syscall_common+0x101/frame 0xfffffe0030b08ab0
--- syscall (2, FreeBSD ELF64, sys_fork), rip = 0x2000028d, rsp =
0x7fffdfffdeb8, rbp = 0x8 ---
KDB: enter: panic
[ thread pid 28070 tid 104637 ]
Stopped at kdb_enter+0x6a: movq $0,kdb_why


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[syzbot]

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