[PATCH 4/7] qemu: Enable iTCO watchdog by disabling its noreboot pin strap

[Daniel P. Berrangé]

On Mon, Jan 23, 2023 at 03:57:53PM +0100, Martin Kletzander wrote:
> In order for the iTCO watchdog to be operational we must disable the noreboot
> pin strap in qemu.  This is the default starting from 8.0 machine types, but
> desirable for older ones as well.  And we can safely do that since that is not
> guest-visible.

Nit-pick, it is not a guest machine ABI visible change. It is a guest
visible behaviour change, in that until now the iTCO watchdog always
existed but was a no-op. Now the iTCO watchdog will fire.

Conceivably someone could have been using the watchdog until now and
not realizing their guest was making it fire.

None the less, I consider it deeply conceptually flawed to be exposing
a watchdog whose action is forced to be a no-op, because it is telling
guests they have a safety net without actually providing the safety
net.  IOW, I think can call this a bug fix, because people have indeed
filed bug reports complaining that the watchdog is broken.

Lets just be very clear in release notes that the default enable
watchdog is a guest visible change, and explain how users might get
it disabled in the worst case (setting action=none)


With regards,
Daniel
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