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Date:   Mon, 18 May 2020 14:37:16 +0100
From:   Mark Rutland <mark.rutland@arm.com>
To:     Will Deacon <will@kernel.org>
Cc:     linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        Sami Tolvanen <samitolvanen@google.com>,
        Kees Cook <keescook@chromium.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Mark Rutland <mark.rutland@am.com>,
        Jann Horn <jannh@google.com>, Ard Biesheuvel <ardb@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>, kernel-team@android.com
Subject: Re: [PATCH 6/6] scs: Move DEFINE_SCS macro into core code
Message-ID: <20200518133716.GD2787@C02TD0UTHF1T.local>
References: <20200515172756.27185-1-will@kernel.org>
 <20200515172756.27185-7-will@kernel.org>
 <20200518121441.GE1957@C02TD0UTHF1T.local>
 <20200518132612.GE32394@willie-the-truck>
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On Mon, May 18, 2020 at 02:26:12PM +0100, Will Deacon wrote:
> On Mon, May 18, 2020 at 01:14:41PM +0100, Mark Rutland wrote:
> > On Fri, May 15, 2020 at 06:27:56PM +0100, Will Deacon wrote:
> > > Defining static shadow call stacks is not architecture-specific, so move
> > > the DEFINE_SCS() macro into the core header file.
> > > 
> > > Signed-off-by: Will Deacon <will@kernel.org>
> > 
> > I think that we'll have to pull this back into arch code if/when we deal
> > with VMAP'd stacks, so I'm not sure this is worthwhile given the
> > diffstat is balanced.
> 
> I dunno, if another architecture wants to use this then having the stuff
> in the core code makes sense to me. I also want to kill asm/scs.h entirely
> and move our asm macros somewhere else where they're not mixed up with the
> C headers.

Thinking about it a bit further, we'd have to make bigger changes anyhow
(to dynamically allocate), but given we can do that for regular stacks
we can probably do something similar here.

So no strong feelings either way on this patch.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>

Mark.