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Date:   Wed, 1 Jan 2020 14:20:47 +0800
From:   Dave Young <dyoung@redhat.com>
To:     Dan Williams <dan.j.williams@intel.com>
Cc:     Ingo Molnar <mingo@redhat.com>,
        Taku Izumi <izumi.taku@jp.fujitsu.com>,
        Michael Weiser <michael@weiser.dinsnail.net>,
        Ard Biesheuvel <ard.biesheuvel@linaro.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-efi <linux-efi@vger.kernel.org>, kexec@lists.infradead.org,
        X86 ML <x86@kernel.org>
Subject: Re: [PATCH v2 4/4] efi: Fix handling of multiple efi_fake_mem=
 entries
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> > Does kexec preserve iomem? I.e. as long as the initial translation of
> > efi entries to e820, and resulting resource tree, is preserved by
> > successive kexec cycles then I think we're ok.
> 
> It will not preserve them automatically, but that can be fixed if
> needed.
> 
> There are two places:
> 1. the in kernel loader, we can do similar with below commit (for Soft
> Reseved instead):
> commit 980621daf368f2b9aa69c7ea01baa654edb7577b
> Author: Lianbo Jiang <lijiang@redhat.com>
> Date:   Tue Apr 23 09:30:07 2019 +0800
> 
>     x86/crash: Add e820 reserved ranges to kdump kernel's e820 table

Oops, that is for kdump only, for kexec, should update the kexec e820
table.  But before doing that we need first to see if this is necessary. 

Thanks
Dave