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Date:   Thu, 28 Sep 2023 06:22:54 -0700
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Subject: Re: [RFC PATCH v2 0/7] Introduce persistent memory pool
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To:     Stanislav Kinsburskii <skinsburskii@linux.microsoft.com>,
        Baoquan He <bhe@redhat.com>
Cc:     tglx@linutronix.de, mingo@redhat.com, bp@alien8.de,
        dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com,
        ebiederm@xmission.com, akpm@linux-foundation.org,
        stanislav.kinsburskii@gmail.com, corbet@lwn.net,
        linux-kernel@vger.kernel.org, kexec@lists.infradead.org,
        linux-mm@kvack.org, kys@microsoft.com, jgowans@amazon.com,
        wei.liu@kernel.org, arnd@arndb.de, gregkh@linuxfoundation.org,
        graf@amazon.de, pbonzini@redhat.com
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From:   Dave Hansen <dave.hansen@intel.com>
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On 9/27/23 09:13, Stanislav Kinsburskii wrote:
> Once deposited, these pages can't be accessed by Linux anymore and thus
> must be preserved in "used" state across kexec, as hypervisor state is
> unware of kexec.

If Linux can't access them, they're not RAM any more.  I'd much rather
remove them from the memory map and move on with life rather than
implement a bunch of new ABI that's got to be handed across kernels.