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Subject: Re: [PATCH v7 08/12] x86/tdx: Add HLT support for TDX guest
From:   "Kuppuswamy, Sathyanarayanan" 
        <sathyanarayanan.kuppuswamy@linux.intel.com>
To:     Borislav Petkov <bp@alien8.de>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, x86@kernel.org,
        Paolo Bonzini <pbonzini@redhat.com>,
        Juergen Gross <jgross@suse.com>, Deep Shah <sdeep@vmware.com>,
        VMware Inc <pv-drivers@vmware.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Joerg Roedel <joro@8bytes.org>, Peter H Anvin <hpa@zytor.com>,
        Dave Hansen <dave.hansen@intel.com>,
        Tony Luck <tony.luck@intel.com>,
        Dan Williams <dan.j.williams@intel.com>,
        Andi Kleen <ak@linux.intel.com>,
        Kirill Shutemov <kirill.shutemov@linux.intel.com>,
        Sean Christopherson <seanjc@google.com>,
        Kuppuswamy Sathyanarayanan <knsathya@kernel.org>,
        linux-kernel@vger.kernel.org
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On 9/23/21 12:33 PM, Kuppuswamy, Sathyanarayanan wrote:
>> Is that explained in the comment in _tdx_halt() where irqs_disabled
>> tells the VMM what to do with the guest - to wake it up or to keep it in
>> virtual halt?
> 
> I think it is left in halt state. Sean, any comment?

I inquired about it and found that the guest will be left in halt
state after non-safe halt call. It is mainly used in CPU off-lining
process.

-- 
Sathyanarayanan Kuppuswamy
Linux Kernel Developer