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Date:   Mon, 31 Jul 2023 18:06:28 +0100
From:   Mark Brown <broonie@kernel.org>
To:     "Edgecombe, Rick P" <rick.p.edgecombe@intel.com>
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Subject: Re: [PATCH v3 21/36] arm64/mm: Implement map_shadow_stack()
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References: <20230731-arm64-gcs-v3-0-cddf9f980d98@kernel.org>
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On Mon, Jul 31, 2023 at 03:56:50PM +0000, Edgecombe, Rick P wrote:
> On Mon, 2023-07-31 at 14:43 +0100, Mark Brown wrote:

> Any thoughts on the questions at the end of this mail?

> https://lore.kernel.org/lkml/7a4c97f68347d4188286c543cdccaa12577cdb9e.camel@intel.com/

Those are:

> Someday when the x86 side is finally upstream I have a manpage for
> map_shadow_stack. Any differences on the arm side would need to be
> documented, but I'm not sure why there should be any differences. Like,
> why not use the same flags? Or have a new flag for token+end marker
> that x86 can use as well?

Ah, it wasn't clear to me that this was a question rather than just
open decisions about the eventual manpage.  Looking again I think what
you're asking about is that I see that at some point in development I
lost the SHADOW_STACK_SET_TOKEN flag which x86 has.  I suspect that was
a rebasing issue as it wasn't a deliberate decision, there's no reason
we couldn't have that.  Other than that and the fact that we add both a
stack swap token and a top of stack marker I'm not aware of any
differences.

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