RE: [PATCH v11 18/20] x86: Handle TDX erratum to reset TDX private memory during kexec() and reboot

[David Laight]

From: kirill.shutemov@xxxxxxxxxxxxxxx
> Sent: 12 June 2023 12:49
> 
> On Mon, Jun 12, 2023 at 10:27:44AM +0000, Huang, Kai wrote:
> > Does it make sense?
> 
> I understand your logic. AFAICS, it is correct (smp_mb() instead of __mb()
> would be better), but it is not justified from complexity PoV.

Given that x86 performs writes pretty much in code order.
Do you need anything more than a compile barrier?

> This lockless exercise gave me a pause to understand.
> 
> Lockless doesn't buy you anything here, only increases complexity.
> Just take a lock.

Indeed...

	David

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