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Subject: Re: [PATCH v3 06/21] x86/virt/tdx: Shut down TDX module in case of
 error
From:   Kai Huang <kai.huang@intel.com>
To:     Sathyanarayanan Kuppuswamy 
        <sathyanarayanan.kuppuswamy@linux.intel.com>,
        linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc:     seanjc@google.com, pbonzini@redhat.com, dave.hansen@intel.com,
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        rafael.j.wysocki@intel.com, reinette.chatre@intel.com,
        dan.j.williams@intel.com, peterz@infradead.org, ak@linux.intel.com,
        kirill.shutemov@linux.intel.com, isaku.yamahata@intel.com
Date:   Tue, 26 Apr 2022 14:12:04 +1200
In-Reply-To: <c3619404-e1d7-6745-0ecc-a759d57d60bf@linux.intel.com>
References: <cover.1649219184.git.kai.huang@intel.com>
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         <82d3cb0b-cebc-d1da-abc1-e802cb8f8ff8@linux.intel.com>
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> > 
> > Prevent all SEAMCALLs on other LPs except TDH.SYS.LP.SHUTDOWN.  The spec defnies
> > shutting down the TDX module as running this SEAMCALl on all LPs, so why just
> > run on a single cpu?  What's the benefit?
> 
> If executing it in one LP prevents SEAMCALLs on all other LPs, I am
> trying to understand why spec recommends running it in all LPs?

Please see 3.1.2 Intel TDX Module Shutdown and Update

The "shutdown" case requires "Execute On" on "Each LP".

Also, TDH.SYS.LP.SHUTDOWN describe this is shutdown on *current* LP.
 
> 
> But the following explanation answers my query. I recommend making a
> note about  it in commit log or comments.

Is above enough to address your question?


-- 
Thanks,
-Kai