arm64 Kernel build for qemu-system-aarch64 ?

arm64 Kernel build for qemu-system-aarch64 ?

[Pintu Agarwal]

Hi All,

I want to build Linux Kernel 4.20 for arm64 and use it on qemu-arm64.
I see that there is a defconfig available in arch/arm64/configs/defconfig
But I am not sure whether it will work for qemu-arm64, and by default
which machine type is supported.

I already have working setup for qemu-arm for both versatile and
vexpress machine. There is already a defconfig available for these
under arch/arm.
So I can build the kernel for it.

But, whether these defconfig are supported for arm64 ?
If anybody have setup for qemu-arm64 kernel, please share the steps.
About rootfs, I am planning to use the arm32 version of busybox itself.


Thanks,
Pintu

Re: arm64 Kernel build for qemu-system-aarch64 ?

[Mark Rutland]

On Fri, Feb 22, 2019 at 07:17:00PM +0530, Pintu Agarwal wrote:
> Hi All,

Hi,

> I want to build Linux Kernel 4.20 for arm64 and use it on qemu-arm64.
> I see that there is a defconfig available in arch/arm64/configs/defconfig
> But I am not sure whether it will work for qemu-arm64, and by default
> which machine type is supported.
> 
> I already have working setup for qemu-arm for both versatile and
> vexpress machine. There is already a defconfig available for these
> under arch/arm.
> So I can build the kernel for it.
> 
> But, whether these defconfig are supported for arm64 ?
> If anybody have setup for qemu-arm64 kernel, please share the steps.
> About rootfs, I am planning to use the arm32 version of busybox itself.

The arm64 defconfig is intended to work for all platforms.

I use that with qemu's '-machine virt'. Assuming you use virtio-net and
virtio-block, no additional drivers are required.

For example, I can boot a defconfig kernel using the followign QEMU options:

qemu-system-aarch64 \
        -m 2048 -smp 4 \
        -net nic \
        -net user,host=10.0.2.10,hostfwd=tcp::65022-:22 \
        -nographic \
        -no-reboot \
        -machine virt,accel=kvm,gic_version=host \
        -cpu host \
        -hda ${FILESYSTEM} \
        -snapshot \
        -kernel ${KERNEL} \
        -append "earlycon root=/dev/vda panic_on_warn"

Thanks,
Mark.

Re: arm64 Kernel build for qemu-system-aarch64 ?

[Pintu Agarwal]

On Fri, Feb 22, 2019 at 7:41 PM Mark Rutland <mark.rutland@arm.com> wrote:
>
> On Fri, Feb 22, 2019 at 07:17:00PM +0530, Pintu Agarwal wrote:
> > Hi All,
>
> Hi,
>
> > I want to build Linux Kernel 4.20 for arm64 and use it on qemu-arm64.
> > I see that there is a defconfig available in arch/arm64/configs/defconfig
> > But I am not sure whether it will work for qemu-arm64, and by default
> > which machine type is supported.
> >
> > I already have working setup for qemu-arm for both versatile and
> > vexpress machine. There is already a defconfig available for these
> > under arch/arm.
> > So I can build the kernel for it.
> >
> > But, whether these defconfig are supported for arm64 ?
> > If anybody have setup for qemu-arm64 kernel, please share the steps.
> > About rootfs, I am planning to use the arm32 version of busybox itself.
>
> The arm64 defconfig is intended to work for all platforms.
>
> I use that with qemu's '-machine virt'. Assuming you use virtio-net and
> virtio-block, no additional drivers are required.
>
> For example, I can boot a defconfig kernel using the followign QEMU options:
>
> qemu-system-aarch64 \
>         -m 2048 -smp 4 \
>         -net nic \
>         -net user,host=10.0.2.10,hostfwd=tcp::65022-:22 \
>         -nographic \
>         -no-reboot \
>         -machine virt,accel=kvm,gic_version=host \
>         -cpu host \
>         -hda ${FILESYSTEM} \
>         -snapshot \
>         -kernel ${KERNEL} \
>         -append "earlycon root=/dev/vda panic_on_warn"
>
> Thanks,
> Mark.

oh thank you so much for your information.
I was exactly looking for this option.
Let me try it on Monday.


Thanks