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Date:   Thu, 28 Sep 2023 10:37:56 -0700
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Subject: Re: [RFC PATCH v2 0/7] Introduce persistent memory pool
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To:     David Hildenbrand <david@redhat.com>,
        Stanislav Kinsburskii <skinsburskii@linux.microsoft.com>,
        Baoquan He <bhe@redhat.com>
Cc:     tglx@linutronix.de, mingo@redhat.com, bp@alien8.de,
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        stanislav.kinsburskii@gmail.com, corbet@lwn.net,
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From:   Dave Hansen <dave.hansen@intel.com>
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On 9/28/23 10:35, David Hildenbrand wrote:
> On 28.09.23 15:22, Dave Hansen wrote:
>> 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.
> 
> The motivation of handling kexec (faster?) in a hyper-v domain doesn't
> sound particularly compelling got me for such features. If you inflated
> memory, just don't allow to kexec. It's been broken for years IIUC.

That's a good point.  What prevents deflating before kexec?