Re: Bhyve: SMBIOS area too small for 65+ vCPUs

On Sun, 2023-05-07 at 11:12 -0600, Rebecca Cran wrote:
> I have a machine with enough cores that I'm able to run large VMs
> with 
> up to 128 or more vCPUs.
> 
> However, it looks like bhyve's SMBIOS area is too small once we reach
> 65 
> vCPUs since I get the following assert failure on boot:
> 
> 
> bcran@maxamd:~/bhyve % sudo ./runbhyve.sh
> fbuf frame buffer base: 0xde214e00000 [sz 16777216]
> Assertion failed: (curaddr - startaddr < SMBIOS_MAX_LENGTH), function
> smbios_build, file /usr/src/usr.sbin/bhyve/smbiostbl.c, line 936.
> Abort trap
> 
> 
>  From looking through the code it appears we can't simply make it
> larger 
> because the ACPI tables after after it.
> 
> 

Hi Rebecca,

I've already ported qemu's fwcfg interface and qemu's acpi table loader
to bhyve. It shouldn't be hard to do the same for smbios.

Do you know how qemu passes his smbios tables to the guest? Is it just
a binary blob or does it requires some patch instruction like acpi?


-- 
Kind regards,
Corvin