On Mon, Jul 12, 2021 at 04:57:37PM +0200, Andrew Jones wrote: > On Fri, Jul 02, 2021 at 06:07:34PM +0800, Yanan Wang wrote: > > It is currently allowed to explicitly specified the topology parameters > > as 0 in the -smp cmdlines, such as -smp cpus=8,maxcpus=0,sockets=0. And > > for the values of cpus/sockets/cores/threads, we always determine that > > they are ommited if either set to 0 in the cmdline(e.g. sockets=0) or > > just not explicitly specified, then we compute the ommited values. > > > > We probably should also treat "maxcpus=0" as ommited and then set the > > value to match smp cpus. This makes cmdlines like "-smp 8, maxcpus=0" > > start to work as "-smp 8,maxcpus=8,sockets=8,cores=1,threads=1". > > > > Note that this patch won't affect any existing working cmdlines, but > > will allow configuration like "-smp cpus=n,maxcpus=0" to be valid. > > Personally, I'd rather see -smp cpus=n,sockets=0 become an error than to > "fix" -smp cpus=n,maxcpus=0.
Yes, a value of 0 is not really something a user should ever be explicitly setting. It is purely an internal default that is used by QEMU to identify when it needs to auto-fill a value. A user should give a non-zero value, or omit the parameter entirely Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|
