Re: git: 76887e84be97 - main - cpuset: increase userland maximum size to 1024

From: Corvin Köhne <corvink_at_FreeBSD.org>
Date: Tue, 09 May 2023 07:43:27 UTC
On Tue, 2023-05-09 at 08:59 +0200, Corvin Köhne wrote:
> On Mon, 2023-05-08 at 18:26 +0000, Ed Maste wrote:
> > The branch main has been updated by emaste:
> > 
> > URL:
> > https://cgit.FreeBSD.org/src/commit/?id=76887e84be975698b14699d7d0dfb157d73e9990
> > 
> > commit 76887e84be975698b14699d7d0dfb157d73e9990
> > Author:     Ed Maste <emaste@FreeBSD.org>
> > AuthorDate: 2023-05-02 20:57:12 +0000
> > Commit:     Ed Maste <emaste@FreeBSD.org>
> > CommitDate: 2023-05-08 18:25:15 +0000
> > 
> >     cpuset: increase userland maximum size to 1024
> >     
> >     Hardware with more than 256 CPU cores is now available and will
> > become
> >     increasingly common.  Bump CPU_MAXSIZE (used for userland
> > cpuset_t
> >     sizing) to 1024 to define the ABI for FreeBSD 14.
> >     
> >     PR:             269572, 271213 [exp-run]
> >     Reviewed by:    mjg, jhb
> >     Relnotes:       yes
> >     Sponsored by:   The FreeBSD Foundation
> >     Differential Revision: https://reviews.freebsd.org/D39941
> > ---
> >  sys/sys/_cpuset.h | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/sys/sys/_cpuset.h b/sys/sys/_cpuset.h
> > index b75ee595da3c..676f9855f384 100644
> > --- a/sys/sys/_cpuset.h
> > +++ b/sys/sys/_cpuset.h
> > @@ -40,7 +40,7 @@
> >  #define        CPU_SETSIZE     MAXCPU
> >  #endif
> >  
> > -#define        CPU_MAXSIZE     256
> > +#define        CPU_MAXSIZE     1024
> >  
> >  #ifndef        CPU_SETSIZE
> >  #define        CPU_SETSIZE     CPU_MAXSIZE
> 
> Hi Ed,
> 
> this somehow breaks bhyve on my system. It immediately exits with
> "vm_run error -1" on startup.
> 
> 

Setting MAXCPU [1] to 1024 as well, solves the issue. Not sure if it's
a regression of your commit or a bhyve bug.

[1]
https://github.com/freebsd/freebsd-src/blob/20d8d9809a8c0a3ddd1d0156e77ec53a1ed95747/sys/amd64/include/param.h#L68


-- 
Kind regards,
Corvin