Skip site navigation (1)Skip section navigation (2)
Date:      Sat, 28 Sep 2013 00:34:41 +0200
From:      "Justin T. Gibbs" <gibbs@freebsd.org>
To:        Benjamin Kaduk <bjkfbsd@gmail.com>
Cc:        "svn-src-head@freebsd.org" <svn-src-head@freebsd.org>, "svn-src-all@freebsd.org" <svn-src-all@freebsd.org>, "src-committers@freebsd.org" <src-committers@freebsd.org>, rmh@freebsd.org
Subject:   Re: svn commit: r255744 - in head/sys: amd64/amd64 amd64/conf amd64/include i386/conf i386/i386 i386/include kern x86/xen xen
Message-ID:  <A12EB34B-DBB6-4790-8EC0-705C7C8CE4C3@freebsd.org>
In-Reply-To: <CAJ5_RoAMpfmkwoeRQ4zvkTFKYvwmOxX5vpqKG-7LqVrAjz5S9Q@mail.gmail.com>
References:  <201309202259.r8KMxMP3084866@svn.freebsd.org> <CAJ5_RoAMpfmkwoeRQ4zvkTFKYvwmOxX5vpqKG-7LqVrAjz5S9Q@mail.gmail.com>

next in thread | previous in thread | raw e-mail | index | archive | help
On Sep 27, 2013, at 11:33 PM, Benjamin Kaduk <bjkfbsd@gmail.com> wrote:

> On Fri, Sep 20, 2013 at 6:59 PM, Justin T. Gibbs <gibbs@freebsd.org> =
wrote:
> Author: gibbs
> Date: Fri Sep 20 22:59:22 2013
> New Revision: 255744
> URL: http://svnweb.freebsd.org/changeset/base/255744
>=20
> Log:
>   Merge Xen PVHVM support into the GENERIC kernel config for both
>   amd64 and i386.
>=20
> I confess to a poor understanding of the reason for existence of =
sys/i386/conf/XEN -- in particular, does this change render that =
configuration obsolete as well as XENHVM?  Maybe -hackers would be a =
better place to ask...
>=20
> Thanks,
>=20
> Ben=20

sys/i386/conf/XEN is for a fully para-virtualized FreeBSD configuration. =
 This means that nothing is emulated and all aspects of the kernel (VM, =
device drivers, etc) are using hypervisor services to do their job.  =
FreeBSD's full PV implementation is not production ready.  However, full =
PV is currently required for DOM0 support and work is currently underway =
to improve it for at least amd64.

HVM with PV optimizations is another guest mode for Xen.  Recent changes =
make it possible for FreeBSD to cleanly detect it is running on Xen and =
enable these optimizations without having to build a custom kernel.  For =
this reason, the XENHVM config was removed.

--
Justin=



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?A12EB34B-DBB6-4790-8EC0-705C7C8CE4C3>