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