Re: [PATCH qemu.git 0/1] hw/arm/virt: add 2x sp804 timer

[Peter Maydell]

On Wed, 30 Nov 2022 at 18:56, ~axelheider <axelheider@git.sr.ht> wrote:
>
> This patch adds timer peripherals to the arm-virt machine. The
> use case is, that this machine is quite useful for testing purposes
> when it comes to non-Linux operating system (seL4 in our case).
> However, is currently lacks a dedicates timer peripheral, so some
> scenarios cannot be tested easily with QEMU. The RTC cannot be
> used, because he resolution is too low. Since the sp804 supposed
> already exists in QEMU, adding these peripherals seems easy and
> it does not appear to break any existing use cases.

Is there a reason you can't use the CPU's built-in generic timer
device ? That is what typical guest code does on this system.
I'm a bit reluctant to add more devices to the virt board
because over time it gradually gets increasingly complicated,
and every new device model we expose to the guest is another
thing that's part of the security attack surface for guest
code trying to escape from a KVM VM.

thanks
-- PMM