Re: missing boot rom: is it really a fatal error?

[Michael S. Tsirkin]

On Mon, May 15, 2023 at 10:02:43AM -0600, Warner Losh wrote:
> 
> 
> On Mon, May 8, 2023 at 5:48 AM Michael S. Tsirkin <mst@redhat.com> wrote:
> 
>     On Mon, May 08, 2023 at 01:42:04PM +0300, Michael Tokarev wrote:
>     > 08.05.2023 13:28, Michael S. Tsirkin wrote:
>     > > On Sun, May 07, 2023 at 08:56:23PM +0300, Michael Tokarev wrote:
>     > ..
>     >
>     > > > I'm about to revert that old change on debian, to make it just a
>     warning instead
>     > > > of an error (the code is different now, but the same principle
>     applies), - because
>     > > > I dislike dependencies which are useless 99.9% of the time and are
>     trivial to
>     > > > install when actually needed.
>     > ..
>     > > I advise against it.
>     > > If you boot guest on a system with boot rom not installed you will not
>     > > be able to migrate to a system with boot rom installed.
>     > > why not? because we don't know how big to make the rom BAR.
>     > > And users will not discover until much much later after they have
>     > > painted themselves into a corner.
>     >
>     > Yes, I know about the migration. Actually there's an old bug report open
>     > against debian qemu package, - the context is similar to the old bios128
>     > vs bios256 thing in qemu upstream, - boot roms might change in size too.
>     >
>     > In this context though, the talk is not about migration at all. The
>     missing
>     > dep is in Xen HVM qemu package, a xen-only build of qemu-system-i386. 
> And
>     > this one fails to start unless the boot roms are provided. It is not 
> even
>     > capable of migration to begin with :)
>     >
>     > Thank you for the reminder, - very useful.
>     >
>     > /mjt
> 
>     I guess we decided we'd rather not handle reports from users about net
>     boot not working. It's true most users don't need net boot but then
>     that's true for most qemu functionality - 99% of users
>     probably need 1% of the functionality. It's just a different 1% for each
>     user...
> 
> 
> Yea, but to every user, their 1% is the most important thing ever...
> Or so it seems some days :)
> 
> Warner

Yep. So I do not think we will be reverting this change in QEMU.

-- 
MST