Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Arvind Sankar <nivedita@alum.mit.edu>
Date:   Wed, 4 Mar 2020 13:50:42 -0500
To:     Ard Biesheuvel <ardb@kernel.org>
Cc:     Arvind Sankar <nivedita@alum.mit.edu>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Andy Lutomirski <luto@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        "H. Peter Anvin" <hpa@zytor.com>,
        the arch/x86 maintainers <x86@kernel.org>,
        linux-efi <linux-efi@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 1/4] x86/mm/pat: Handle no-GBPAGES case correctly in
 populate_pud
Message-ID: <20200304185042.GA281042@rani.riverdale.lan>
References: <20200303205445.3965393-1-nivedita@alum.mit.edu>
 <20200303205445.3965393-2-nivedita@alum.mit.edu>
 <CAKv+Gu_LmntqGjkakR0-SFSCR+JF+CFeKyc=5qzOdpn4wTvKhw@mail.gmail.com>
 <20200304154908.GB998825@rani.riverdale.lan>
 <CAKv+Gu-Xo2zj9_N+K8FrpBstgU57GZvWO-pDr4tRAODhsYzW-A@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
In-Reply-To: <CAKv+Gu-Xo2zj9_N+K8FrpBstgU57GZvWO-pDr4tRAODhsYzW-A@mail.gmail.com>
User-Agent: Mutt/1.10.1 (2018-07-13)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Wed, Mar 04, 2020 at 07:44:50PM +0100, Ard Biesheuvel wrote:
> 
> I've tried a couple of different ways, but I can't seem to get my
> memory map organized in the way that will trigger the error.

What does yours look like? efi_merge_regions doesn't merge everything
that will eventually be mapped the same way, so if there are some
non-conventional memory regions scattered over the address space, it
might be breaking up the mappings to the point where this doesn't
trigger.