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Date:   Fri, 30 Jun 2023 11:22:32 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     "Huang, Kai" <kai.huang@intel.com>
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Subject: Re: [PATCH v12 07/22] x86/virt/tdx: Add skeleton to enable TDX on
 demand
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On Thu, Jun 29, 2023 at 12:15:13AM +0000, Huang, Kai wrote:

> > 	Can be called locally or through an IPI function call.
> > 
> 
> Thanks.  As in another reply, if using spinlock is OK, then I think we can say
> it will be called either locally or through an IPI function call.  Otherwise, we
> do via a new separate function tdx_global_init() and no lock is needed in that
> function.  The caller should call it properly.

IPI must use raw_spinlock_t. I'm ok with using raw_spinlock_t if there's
actual need for that, but the code as presented didn't -- in comments or
otherwise -- make it clear why it was as it was.

TDX not specifying time constraints on the various TD/SEAM-CALLs is
ofcourse sad, but alas.