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Date:   Wed, 27 Apr 2022 07:24:03 -0700
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Subject: Re: [PATCH v3 05/21] x86/virt/tdx: Detect P-SEAMLDR and TDX module
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To:     Kai Huang <kai.huang@intel.com>, linux-kernel@vger.kernel.org,
        kvm@vger.kernel.org
Cc:     seanjc@google.com, pbonzini@redhat.com, len.brown@intel.com,
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        reinette.chatre@intel.com, dan.j.williams@intel.com,
        peterz@infradead.org, ak@linux.intel.com,
        kirill.shutemov@linux.intel.com,
        sathyanarayanan.kuppuswamy@linux.intel.com,
        isaku.yamahata@intel.com
References: <cover.1649219184.git.kai.huang@intel.com>
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 <98af78402861b1982607c5fd14b0c89403c042a6.camel@intel.com>
From:   Dave Hansen <dave.hansen@intel.com>
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On 4/26/22 17:01, Kai Huang wrote:
> On Tue, 2022-04-26 at 13:56 -0700, Dave Hansen wrote:
>> On 4/5/22 21:49, Kai Huang wrote:
>>> The P-SEAMLDR (persistent SEAM loader) is the first software module that
>>> runs in SEAM VMX root, responsible for loading and updating the TDX
>>> module.  Both the P-SEAMLDR and the TDX module are expected to be loaded
>>> before host kernel boots.
>>
>> Why bother with the P-SEAMLDR here at all?  The kernel isn't loading the
>> TDX module in this series.  Why not just call into the TDX module directly?
> 
> It's not absolutely needed in this series.  I choose to detect P-SEAMLDR because
> detecting it can also detect the TDX module, and eventually we will need to
> support P-SEAMLDR because the TDX module runtime update uses P-SEAMLDR's
> SEAMCALL to do that.
> 
> Also, even for this series, detecting the P-SEAMLDR allows us to provide the P-
> SEAMLDR information to user at a basic level in dmesg:
> 
> [..] tdx: P-SEAMLDR: version 0x0, vendor_id: 0x8086, build_date: 20211209,
> build_num 160, major 1, minor 0
> 
> This may be useful to users, but it's not a hard requirement for this series.

We've had a lot of problems in general with this code trying to do too
much at once.  I thought we agreed that this was going to only contain
the minimum code to make TDX functional.  It seems to be creeping to
grow bigger and bigger.

Am I remembering this wrong?