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From: Leonardo Bras <leo.bras@arm.com>
To: Mark Brown <broonie@kernel.org>
Cc: Leonardo Bras <leo.bras@arm.com>,
	Catalin Marinas <catalin.marinas@arm.com>,
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Subject: Re: [PATCH v20 05/14] KVM: arm64: Set PSTATE.EXLOCK when entering an exception
Date: Thu,  3 Sep 2026 17:40:12 +0100
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On Thu, Sep 03, 2026 at 05:20:32PM +0100, Mark Brown wrote:
> > > +	// PSTATE.EXLOCK is set to 0 upon any exception to a higher
> > > +	// EL, or to GCSCR_ELx.EXLOCKEN for an exception to the same
> > > +	// exception level.  See ARM DDI 0487 R_WTXBY.
> > > +	new |= compute_exlock(vcpu, mode, target_mode);
> 
> > Same nit: am I really setting one bit here? or could be 
> > more stuff depending on the parameters? Having an "if (cond) new |= bit"
> > seems more clear to what is being done, without needing to read the comment 
> > above.
> 
> The goal with the comment is to explain the rule that the code is
> implementing in a style similar to all the other field updates in the
> same function.

Oh, right, to be clear:
I am not questioning the usefulness of the comment here.

It's more about "new |= function()" thing, as it's not immediately clear 
what is being set unless I read the comment or read the function, as in the 
case "if (function()) new |= bit" I may not immediately see the condition 
but I know whatever it can be, it will only decide if I do or don't set 
this given bit.

Thanks!
Leo