From mboxrd@z Thu Jan  1 00:00:00 1970
From: Arnd Bergmann <arnd@arndb.de>
Subject: Re: Installing kernel headers in kvm-kmod
Date: Thu, 10 Dec 2009 15:50:22 +0100
Message-ID: <200912101550.22930.arnd@arndb.de>
References: <4B20F27D.3000006@codemonkey.ws> <4B20F914.8020003@siemens.com>
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Cc: Anthony Liguori <anthony@codemonkey.ws>,
	Avi Kivity <avi@redhat.com>,
	Marcelo Tosatti <mtosatti@redhat.com>,
	"kvm-devel" <kvm@vger.kernel.org>
To: Jan Kiszka <jan.kiszka@siemens.com>
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On Thursday 10 December 2009, Jan Kiszka wrote:
> Anthony Liguori wrote:
> > QEMU 0.12.0-rc1 does not support KVM
> > https://bugs.launchpad.net/bugs/494500
> > 
> > Boils down to the fact that 1) we don't include kernel headers in qemu
> > (whereas qemu-kvm does) and 2) kvm-kmod does not install those headers
> > on make install.
> > 
> > I think we've discussed (2) as being the preferred solution.  Does
> > everyone agree with that?  Anyone care to volunteer to make the change? :-)
> > 
> I've pushed a half-tested approach into kvm-kmod's next branch. Feel
> free to test/fix/enhance it.

This would work, but installing to /usr/include/linux/kvm.h will confuse
distro package managers a lot, because that location belongs to the glibc
or libc-linux-headers or some other package already.

If you want to install the headers from kvm-kmod, I would recommend
doing it in a different path, e.g. /usr/include/kvm-kmod/{linux,asm}.
qemu can then add -I/usr/include/kvm-kmod to it's default include
path and get the kvm-kmod version if that's installed or the distro
version otherwise.

It may also be useful to do the equivalent of 'make headers_install'
from the kernel, to remove all "#ifdef __KERNEL__" sections and
sparse annotations from the header files, but it should also work
without that.

	Arnd