Re: [PATCH] x86: temporarily remove all attempts to provide setup_data

[Jason A. Donenfeld]

On Wed, Feb 8, 2023 at 3:13 PM Michael S. Tsirkin <mst@xxxxxxxxxx> wrote:
>
> On Wed, Feb 08, 2023 at 03:08:35PM -0300, Jason A. Donenfeld wrote:
> > All attempts at providing setup_data have been made as an iteration on
> > whatever was there before, stretching back to the original
> > implementation used for DTBs that [mis]used the kernel image itself.
> > We've now had a dozen rounds of bugs and hacks, and the result is
> > turning into a pile of unmaintainable and increasingly brittle hacks.
> >
> > Let's just rip out all the madness and start over. We can re-architect
> > this based on having a separate standalone setup_data file, which is how
> > it should have been done in the first place. This is a larger project
> > with a few things to coordinate, but we can't really begin thinking
> > about that while trying to play whack-a-mole with the current buggy
> > implementation.
> >
> > So this commit removes the setup_data setting from x86_load_linux(),
> > while leaving intact the infrastructure we'll need in the future to try
> > again.
> >
> > Cc: Michael S. Tsirkin <mst@xxxxxxxxxx>
> > Cc: Dov Murik <dovmurik@xxxxxxxxxxxxx>
> > Cc: Tom Lendacky <thomas.lendacky@xxxxxxx>
> > Cc: Gerd Hoffmann <kraxel@xxxxxxxxxx>
> > Cc: Daniel P. Berrangé <berrange@xxxxxxxxxx>
> > Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> > Cc: Richard Henderson <richard.henderson@xxxxxxxxxx>
> > Cc: H. Peter Anvin <hpa@xxxxxxxxx>
> > Cc: Philippe Mathieu-Daudé <philmd@xxxxxxxxxx>
> > Cc: Nathan Chancellor <nathan@xxxxxxxxxx>
> > Cc: Borislav Petkov <bp@xxxxxxxxx>
> > Cc: Eric Biggers <ebiggers@xxxxxxxxxx>
> > Signed-off-by: Jason A. Donenfeld <Jason@xxxxxxxxx>
>
> I think I'll be happier if this is just a revert of
> the relevant commits in reverse order to make life easier
> for backporters.
> Unless that's too much work as we made other changes around
> this code?

I think that's going to be messy. And it won't handle the dtb stuff
either straightforwardly.