On Thu, 5 May 2022 at 11:17, Jan Kiszka <jan.kis...@siemens.com> wrote: > > On 05.05.22 10:40, Peter Maydell wrote: > > On Sun, 1 May 2022 at 19:07, Jan Kiszka <jan.kis...@web.de> wrote: > >> > >> From: Jan Kiszka <jan.kis...@siemens.com> > >> > >> The virt machine lacks a watchdog so far while the sbsa-ref has a simple > >> model that is also supported by Linux and even U-Boot. Let's take it to > >> allow, e.g., system integration tests of A/B software update under > >> watchdog monitoring. > >> > >> Signed-off-by: Jan Kiszka <jan.kis...@siemens.com> > > > > The virt board has a PCI bus, and QEMU has a model of a > > PCI watchdog device -- the i6300esb. Can you use that? > > While one could do that, it implies using completely alien Intel x86 > host controller bits on this platform. And, thus, would require changes > in firmware (e.g. adding a driver to U-Boot).
> > In general I much prefer it if we can support use cases in > > virt via pluggable PCI devices rather than hard-wired MMIO > > devices -- it means that only users who want the functionality > > need to have the exposed attack surface area of the device > > present in their VM. > > Valid point - would making this opt-in via a machine feature be sufficient? I really strongly prefer the PCI device solution. If you don't like the i6300esb you could write a model of some other PCI device. thanks -- PMM