On Mon, 25 Oct 2021, Juergen Gross wrote:
> On 22.10.21 21:41, Stefano Stabellini wrote:
> > +Juergen
> > 
> > On Fri, 22 Oct 2021, Andrew Cooper wrote:
> > > On 22/10/2021 00:08, Stefano Stabellini wrote:
> > > > +# build depends
> > > > +RUN apt-get update && \
> > > > +    apt-get --quiet --yes install \
> > > > +        build-essential \
> > > > +        libssl-dev \
> > > > +        bc \
> > > > +        curl \
> > > > +        flex \
> > > > +        bison \
> > > > +        libelf-dev \
> > > > +        && \
> > > > +    \
> > > > +    # Build the kernel
> > > > +    curl -fsSLO
> > > > https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-"$LINUX_VERSION".tar.xz
> > > > && \
> > > > +    tar xvJf linux-"$LINUX_VERSION".tar.xz && \
> > > > +    cd linux-"$LINUX_VERSION" && \
> > > > +    make defconfig && \
> > > > +    make xen.config && \
> > > > +    cp .config .config.orig && \
> > > > +    cat .config.orig | grep XEN | grep =m |sed 's/=m/=y/g' >> .config
> > > > && \
> > > > +    make -j$(nproc) bzImage && \
> > > 
> > > defconfig is huuuuge.  Can we use tinyconfig instead?
> > > 
> > > Also, you want to turn off CONFIG_MODULES seeing as you only copy
> > > bzImage to the test.
> > > 
> > > This also fixes the fact that `grep XEN` also matches CONFIG_NETXEN_NIC
> > > which has nothing to do with Xen.
> > 
> > Tinyconfig would be a good idea but it crashes on QEMU with the appended
> > boot log. I did:
> > 
> > # make tinyconfig
> > # make xen.config
> > # make bzImage
> > 
> > Of course we could have our own tailored special kernel config for this
> > kernel but I like the simplicify of "make tinyconfig" or "make
> > defconfig" followed by "make xen.config".
> > 
> > Unless you know one kconfig option or two that we need to add to
> > tinyconfig to make it work my preference is to go with defconfig for
> > now.
> 
> You will need to add the dom0 and SMP related config options at least.
> 
> I'll have a look at config.xen, which is a little bit weird: it
> configures the backends, but not dom0.

Thanks, it would be good if make tinyconfig && make xen.config would
just work on QEMU. In the meantime I'll keep defconfig for this test, we
can always improve later.