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Date:   Mon, 12 Jun 2023 06:47:08 -0700
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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 6/12/23 03:27, Huang, Kai wrote:
> So I think a __mb() after setting tdmr->pamt_4k_base should be good enough, as
> it guarantees when setting to any pamt_*_size happens, the valid pamt_4k_base
> will be seen by other cpus.
> 
> Does it make sense?

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.