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Date:   Wed, 28 Jun 2023 15:35:41 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     "Huang, Kai" <kai.huang@intel.com>
Cc:     "kirill.shutemov@linux.intel.com" <kirill.shutemov@linux.intel.com>,
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        "Yamahata, Isaku" <isaku.yamahata@intel.com>,
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Subject: Re: [PATCH v12 07/22] x86/virt/tdx: Add skeleton to enable TDX on
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On Wed, Jun 28, 2023 at 12:28:12AM +0000, Huang, Kai wrote:
> On Tue, 2023-06-27 at 22:37 +0000, Huang, Kai wrote:
> > > > 
> > > > +/*
> > > > + * Do the module global initialization if not done yet.
> > > > + * It's always called with interrupts and preemption disabled.
> > > > + */
> > > 
> > > If interrupts are always disabled why do you need _irqsave()?
> > > 
> > 
> > I'll remove the _irqsave().
> > 
> > AFAICT Isaku preferred this for additional security, but this is not
> > necessary.
> > 
> > 
> 
> Damn.  I think we can change the comment to say this function is called with
> preemption being disabled, but _can_ be called with interrupt disabled.  And we
> keep using the _irqsave() version.
> 
> 	/*
> 	 * Do the module global initialization if not done yet.  It's always
> 	 * called with preemption disabled and can be called with interrupts
> 	 * disabled.
> 	 */

That's still not explaining *why*, what you want to say is:

	Can be called locally or through an IPI function call.