Re: [Qemu-devel] [PATCH] ppc/pnv: Warn when using -initrd and low ram

[Joel Stanley]

On Tue, 16 Jul 2019 at 08:53, David Gibson <address@hidden> wrote:
>
> On Tue, Jul 16, 2019 at 09:39:36AM +0200, Cédric Le Goater wrote:
> > > Provide a helpful message for users so they don't go reporting bugs to
> > > kernel developers.
> > >
> > > Signed-off-by: Joel Stanley <address@hidden>
> > > ---
> > > We could solve this in other ways, such as warn when loading the initrd
> > > outside of RAM, or load it within the known boundaries or RAM, but after
> > > hitting this myself I wanted to start the discussion.
> >
> > We should also increase :
> >
> >     mc->default_ram_size = 1 * GiB;
> >
> > to 2 or 4 GiB. I always use 4.
>
> It seems to be increasing the default addresses the real problem in
> practice.  Putting in a warning but still letting you do it, rather
> than relocating where we load the image based on the ram size seems
> kind of roundabout.

I agree. I'll send a patch to do that.

> > at the beginning of this routine we have :
> >
> >     /* allocate RAM */
> >     if (machine->ram_size < (1 * GiB)) {
> >         warn_report("skiboot may not work with < 1GB of RAM");
> >     }
> >
> > and we should exit instead.

Yeah, perhaps. If someone is playing with some other bit of firmware
code then there's no reason not to continue. I'll leave this one alone
for now.

Cheers,

Joel