From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ingo Molnar <mingo@kernel.org>
Subject: Re: [PATCH v2 00/12] treewide: break dependencies on x86's RM header
Date: Wed, 27 Nov 2019 08:20:57 +0100
Message-ID: <20191127072057.GB94748@gmail.com>
References: <20191126165417.22423-1-sean.j.christopherson@intel.com>
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To: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>, x86@kernel.org, "Rafael J. Wysocki" <rjw@rjwysocki.net>, Len Brown <len.brown@intel.com>, Pavel Machek <pavel@ucw.cz>, Tony Luck <tony.luck@intel.com>, Fenghua Yu <fenghua.yu@intel.com>, Peter Zijlstra <peterz@infradead.org>, Arnaldo Carvalho de Melo <acme@kernel.org>, Mark Rutland <mark.rutland@arm.com>, Alexander Shishkin <alexander.shishkin@linux.intel.com>, Jiri Olsa <jolsa@redhat.com>, Namhyung Kim <namhyung@kernel.org>, "H. Peter Anvin" <hpa@zytor.com>, Steven Rostedt <rostedt@goodmis.org>, Ard Biesheuvel <ard.biesheuvel@linaro.org>, Darren Hart <dvhart@infradead.org>, Andy Shevchenko <andy@infradead.org>, Nadav Amit <nadav.amit@gmail.com>
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* Sean Christopherson <sean.j.christopherson@intel.com> wrote:

> x86's asm/realmode.h, which defines low level structures, variables and
> helpers used to bring up APs during SMP boot, ends up getting included in
> practically every nook and cranny of the kernel because the address used
> by ACPI for resuming from S3 also happens to be stored in the real mode
> header, and ACPI bleeds the dependency into its widely included headers.
> 
> As a result, modifying realmode.h for even the most trivial change to the
> boot code triggers a full kernel rebuild, which is frustrating to say the
> least as it some of the most difficult code to get exactly right *and* is
> also some of the most functionally isolated code in the kernel.
> 
> To break the kernel's widespread dependency on realmode.h, add a wrapper
> in the aforementioned ACPI S3 code to access the real mode header instead
> of derefencing the header directly in asm/acpi.h and thereby exposing it
> to the world via linux/acpi.h.
> 
> v2:
>   - Rebased on tip/x86/cleanups, commit b74374fef924 ("x86/setup: Enhance
>     the comments").
>   - Use acpi_get_wakeup_address() as new function name. [Boris and Pavel]
>   - Capture acpi_get_wakeup_address() in a local address. [Pavel]
>   - Collect acks.  I didn't add Rafael's acks on patches 11 and 12 due to
>     the above changes.
>   - Explicitly call out the removal of <asm/realmode.h> from <asm/acpi.h>
>     in patch 12. [Ingo]
>   - Remove superfluous Fixes: tags. [Ard]

You didn't include every patch from v1 though, such us my fix to Quark:

  [PATCH] x86/platform/intel/quark: Explicitly include linux/io.h for virt_to_phys()

I've applied that one too and your updated patches, and it's now all 
pushed out into tip:WIP.core/headers.

Thanks,

	Ingo