RE: [PATCH 4.4 05/27] x86/efi: Build our own page table structures

Ghannam, Yazen
2017-12-12T17:24:38Z

> -----Original Message-----
> From: Greg Kroah-Hartman [mailto:gregkh@linuxfoundation.org]
> Sent: Sunday, December 10, 2017 4:27 PM
> To: Ben Hutchings <ben.hutchings@codethink.co.uk>; Ghannam, Yazen
> <Yazen.Ghannam@amd.com>
> Cc: linux-kernel@vger.kernel.org; stable@vger.kernel.org; Matt Fleming
> <matt@codeblueprint.co.uk>; Borislav Petkov <bp@suse.de>; Andrew
> Morton <akpm@linux-foundation.org>; Andy Lutomirski
> <luto@amacapital.net>; Andy Lutomirski <luto@kernel.org>; Ard Biesheuvel
> <ard.biesheuvel@linaro.org>; Borislav Petkov <bp@alien8.de>; Brian Gerst
> <brgerst@gmail.com>; Dave Jones <davej@codemonkey.org.uk>; Denys
> Vlasenko <dvlasenk@redhat.com>; H. Peter Anvin <hpa@zytor.com>; Linus
> Torvalds <torvalds@linux-foundation.org>; Peter Zijlstra
> <peterz@infradead.org>; Sai Praneeth Prakhya
> <sai.praneeth.prakhya@intel.com>; Stephen Smalley <sds@tycho.nsa.gov>;
> Thomas Gleixner <tglx@linutronix.de>; Toshi Kani <toshi.kani@hp.com>;
> linux-efi@vger.kernel.org; Ingo Molnar <mingo@kernel.org>; Ghannam,
> Yazen <Yazen.Ghannam@amd.com>; Alex Thorlton <athorlton@sgi.com>
> Subject: Re: [PATCH 4.4 05/27] x86/efi: Build our own page table structures
>
> On Thu, Dec 07, 2017 at 10:43:49PM +0000, Ben Hutchings wrote:
> > On Mon, 2017-12-04 at 16:59 +0100, Greg Kroah-Hartman wrote:
> > > 4.4-stable review patch.  If anyone has any objections, please let me
> know.
> > >
> > > ------------------
> > >
> > > From: Matt Fleming <matt@codeblueprint.co.uk>
> > >
> > > commit 67a9108ed4313b85a9c53406d80dc1ae3f8c3e36 upstream.
> > [...]
> >
> > It looks like this will cause regressions unless you also apply:
> >
> > 21cdb6b56843 x86/mm: Page align the '_end' symbol to avoid pfn
> conversion bugs
> > b61a76f8850d x86/efi: Map RAM into the identity page table for mixed
> mode
> > 753b11ef8e92 x86/efi: Setup separate EFI page tables in kexec paths
> >
> > and possibly also:
> >
> > 08914f436bdd x86/platform/UV: Bring back the call to map_low_mmrs in
> uv_system_init
> > 683ad8092cd2 x86/efi: Fix 7-parameter efi_call()s
> > 80e75596079f efi: Convert efi_call_virt() to efi_call_virt_pointer()
> > d1be84a232e3 x86/uv: Update uv_bios_call() to use efi_call_virt_pointer()
>
> Ugh, that's a mess. Yazen is the one who reported this patch, and 2
> others, were needed to resolve an issue on their hardware.
>
> Yazen, any thoughts here? Should I just revert the 3 patches, or do you
> also feel I need all 7 of these to ensure everything works properly?
>

I think it's okay to revert the 3 patches.

Thanks,
Yazen