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Date:   Tue, 5 Dec 2023 08:53:48 -0800
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Subject: Re: [PATCH v15 22/23] x86/mce: Improve error log of kernel space TDX
 #MC due to erratum
From:   Sean Christopherson <seanjc@google.com>
To:     Dave Hansen <dave.hansen@intel.com>
Cc:     Kai Huang <kai.huang@intel.com>,
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On Tue, Dec 05, 2023, Dave Hansen wrote:
> On 12/4/23 18:04, Sean Christopherson wrote:
> > Joking aside, why shove TDX module ownership into KVM?  It honestly sounds like
> > a terrible fit, even without the whole TDX-IO mess.  KVM state is largely ephemeral,
> > in the sense that loading and unloading kvm.ko doesn't allocate/free much memory
> > or do all that much initialization or teardown.
> 
> Yeah, you have a good point there.  We really do need some core code to
> manage VMXON/OFF now that there is increased interest outside of
> _purely_ running VMs.
> 
> For the purposes of _this_ patch, I think I'm happy to leave open the
> possibility that SEAMCALL can simply fail due to VMXOFF.  For now, it
> means that we can't attribute #MC's to the PAMT unless a VM is running
> but that seems like a reasonable compromise for the moment.

+1

> Once TDX gains the ability to "pin" VMXON, the added precision here will
> be appreciated.