RE: [PATCH] x86/hyperv: Suspend/resume the VP assist page for hibernation

[Dexuan Cui]

> From: Wei Liu <wei.liu@xxxxxxxxxx>
> Sent: Monday, April 20, 2020 5:08 AM
> 
> I would suggest make this clear in the commit message to not give the
> impression that Hyper-V has this weird behaviour of corrupting guest
> memory for no reason.
> 
> We can replace the paragraph starting with "The issue is: ..." with:
> 
> ---
> Linux needs to update Hyper-V the correct VP assist page to prevent
> Hyper-V from writing to a stale page, which causes guest memory
> corruption.  The memory corruption may have caused some of the hangs and
> triple faults we saw during non-boot CPUs resume.
> ---
> This What do you think?

This version is much better. I'll use it. Thanks, Wei!

I'll post a v2 with the updated comments. I'll document Vitaly's concern about
nested virtualization in the comment.
 
Thanks,
-- Dexuan