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Date:   Sat, 30 Jul 2022 00:02:34 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Cc:     Jonathan Corbet <corbet@lwn.net>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        Dave Hansen <dave.hansen@linux.intel.com>, x86@kernel.org,
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        linux-kernel@vger.kernel.org, stable@vger.kernel.org,
        tony.luck@intel.com, antonio.gomez.iglesias@linux.intel.com,
        Daniel Sneddon <daniel.sneddon@linux.intel.com>,
        andrew.cooper3@citrix.com, Josh Poimboeuf <jpoimboe@kernel.org>
Subject: Re: [RESEND RFC PATCH] x86/bugs: Add "unknown" reporting for MMIO
 Stale Data
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On Fri, Jul 29, 2022 at 02:46:27PM -0700, Pawan Gupta wrote:
> Let me see if there is a way to distinguish between 4. and 5. below:
> 
>    CPU category				  X86_BUG_MMIO_STALE_DATA	X86_BUG_MMIO_UNKNOWN
> -----------------------------------------------------------------------------------------------
> 1. Known affected (in cpu list)			1				0
> 2. CPUs with HW immunity (MMIO_NO=1)		0				0
> 3. Other vendors				0				0
> 4. Older Intel CPUs				0				1
> 5. Not affected current CPUs (but MMIO_NO=0)	0				?

Not affected current CPUs should be arch_cap_mmio_immune() == true, no?

-- 
Regards/Gruss,
    Boris.

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