[fedora-arm] kernel build on fc19 aarch64 model

[Sandeepa Prabhu]

On 2 January 2014 17:00, Richard W.M. Jones <rjones at redhat.com> wrote:
> On Thu, Jan 02, 2014 at 04:37:45PM +0530, Sandeepa Prabhu wrote:
>> Hi,
>>
>> I am trying to build kernel on fc19 aarch64 image based on v8 Foundation model.
>> kernel branch is based on "armv8-uefi-v3.13rc" and toolchain: gcc
>> version 4.8.1 20130920 (Red Hat 4.8.1-10) (GCC)   - using 8GB RAM.
>>
>> Kernel build is taking for me more than 12 hours, and adding more
>> threads (-j6 etc) does not improve the build speed. Is this expected ?
>
> Yes :-(
>
>> or is there a step to improve kernel build?
>
> qemu-arm64 userspace emulation[1] is a little bit faster than the
> Foundation Model, but (a) it's limited to userspace emulation (fine
> for compiling things) and (b) it's still damn slow.  It will still
> take you hours to compile this way.
>
> So ... cross-compiling, assuming you just want to build the kernel and
> don't want to build an RPM.  On your fast x86-64 host, install
> gcc-aarch64-linux-gnu and do something like this:
>
>   make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu-
Ok, so cross-compiling would work for me, how do I install the built
kernel image (EFI version) on the disk image, is it just copying
vmlinux onto /boot/vmlinux-***?

Thanks,
Sandeepa
>
> Rich.
>
> [1] http://rwmj.wordpress.com/2013/12/22/how-to-run-aarch64-binaries-on-an-x86-64-host-using-qemu-userspace-emulation/#content
>
> --
> Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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