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Subject: Re: [Xen-devel] [PATCH v6 10/34] x86, x86/mm, x86/xen, olpc: Use
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Cc: Brijesh Singh <brijesh.singh@amd.com>,
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        Thomas Gleixner <tglx@linutronix.de>,
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        xen-devel <xen-devel@lists.xen.org>,
        Paolo Bonzini <pbonzini@redhat.com>
From: Boris Ostrovsky <boris.ostrovsky@oracle.com>
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Date: Fri, 9 Jun 2017 15:42:24 -0400
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>>
>> PV guests don't go through Linux x86 early boot code. They start at
>> xen_start_kernel() (well, xen-head.S:startup_xen(), really) and  merge
>> with baremetal path at x86_64_start_reservations() (for 64-bit).
>>
>
> Ok, I don't think anything needs to be done then. The sme_me_mask is set
> in sme_enable() which is only called from head_64.S. If the sme_me_mask
> isn't set then SME won't be active. The feature will just report the
> capability of the processor, but that doesn't mean it is active. If you
> still want the feature to be clobbered we can do that, though.

I'd prefer to explicitly clear to avoid any ambiguity.

-boris