Re: [PATCH 3/6] arm64: scs: Use 'scs_sp' register alias for x18

[Will Deacon]

On Mon, May 18, 2020 at 12:55:47PM +0100, Mark Rutland wrote:
> On Fri, May 15, 2020 at 06:27:53PM +0100, Will Deacon wrote:
> > x18 holds the SCS stack pointer value, so introduce a register alias to
> > make this easier to read in assembly code.
> > 
> > Signed-off-by: Will Deacon <will@xxxxxxxxxx>
> 
> I scanned through arm64 for all instances of x18, and it looks like
> you've covered all the relevant uses here. In kvm we save/restore x18 a
> bunch becasue it might be a platform register, but we do that
> unconditionally and without knowledge of what it contains, so I think
> that's fine to leave as-is. Therefore:
> 
> Reviewed-by: Mark Rutland <mark.rutland@xxxxxxx>
> 
> As an aside, the comment in entry-ftrace.S is now stale where it says
> that x18 is safe to clobber. I can send a patch to clean that up, unless
> you want to do that yourself.

Thanks, I'll fix that up (see below). Also, apologies for typo'ing your
email address when I sent this out on Friday.

Will

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