Date:   Wed, 8 Feb 2023 13:18:37 -0500
From:   "Michael S. Tsirkin" <mst@redhat.com>
To:     "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc:     qemu-devel@nongnu.org, x86@kernel.org,
        linux-kernel@vger.kernel.org, Dov Murik <dovmurik@linux.ibm.com>,
        Tom Lendacky <thomas.lendacky@amd.com>,
        Gerd Hoffmann <kraxel@redhat.com>,
        Daniel P =?iso-8859-1?Q?=2E_Berrang=E9?= <berrange@redhat.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Richard Henderson <richard.henderson@linaro.org>,
        "H . Peter Anvin" <hpa@zytor.com>,
        Philippe =?iso-8859-1?Q?Mathieu-Daud=E9?= <philmd@linaro.org>,
        Nathan Chancellor <nathan@kernel.org>,
        Borislav Petkov <bp@alien8.de>,
        Eric Biggers <ebiggers@kernel.org>
Subject: Re: [PATCH] x86: temporarily remove all attempts to provide
 setup_data
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 <CAHmME9rMnbGDZ+Rq8ao=gZd10kBp5ni=73HcPpFC58ChoKZObA@mail.gmail.com>
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On Wed, Feb 08, 2023 at 03:14:38PM -0300, Jason A. Donenfeld wrote:
> On Wed, Feb 8, 2023 at 3:13 PM Michael S. Tsirkin <mst@redhat.com> 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@redhat.com>
> > > Cc: Dov Murik <dovmurik@linux.ibm.com>
> > > Cc: Tom Lendacky <thomas.lendacky@amd.com>
> > > Cc: Gerd Hoffmann <kraxel@redhat.com>
> > > Cc: Daniel P. Berrang? <berrange@redhat.com>
> > > Cc: Paolo Bonzini <pbonzini@redhat.com>
> > > Cc: Richard Henderson <richard.henderson@linaro.org>
> > > Cc: H. Peter Anvin <hpa@zytor.com>
> > > Cc: Philippe Mathieu-Daud? <philmd@linaro.org>
> > > Cc: Nathan Chancellor <nathan@kernel.org>
> > > Cc: Borislav Petkov <bp@alien8.de>
> > > Cc: Eric Biggers <ebiggers@kernel.org>
> > > Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
> >
> > 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.

List of Fixes tags so people can at least figure out whether they
have a version that needs this fix then?

-- 
MST