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Subject: Re: [PATCH v11 18/20] x86: Handle TDX erratum to reset TDX private
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To:     "Huang, Kai" <kai.huang@intel.com>,
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From:   Dave Hansen <dave.hansen@intel.com>
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On 6/19/23 17:56, Huang, Kai wrote:
> Any comments to below?

Nothing that I haven't already said in this thread:

> Just use a normal old atomic_t or set_bit()/test_bit().  They have
> built-in memory barriers are are less likely to get botched.

I kinda made a point of literally suggesting "atomic_t or
set_bit()/test_bit()".  I even told you why: "built-in memory barriers".

Guess what READ/WRITE_ONCE() *don't* have.  Memory barriers.