From mboxrd@z Thu Jan  1 00:00:00 1970
From: hch@lst.de (Christoph Hellwig)
Date: Fri, 17 May 2019 11:35:16 +0200
Subject: [PATCHv2 6/6] nvme-pci: Use host managed power state for suspend
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Message-ID: <20190517093516.GA17006@lst.de>

On Fri, May 17, 2019@11:17:52AM +0200, Rafael J. Wysocki wrote:
> AFAICS, using DMA while creating a hibernation snapshot image of
> memory would not be a good idea, so the host memory buffer should be
> disabled during the "freeze" stage or hibernation (and it can be
> re-enabled when that stage is complete).

Once we'd disable the HMB the harm is done, so no point in re-enabling
it.  What would this mean in terms of ops?  Only disable in
freeze_noirq?  Or stick to the simple ops and find another helper
that indicates we are doing a hibernation?