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Date: Fri, 3 Dec 2021 17:34:24 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Alexander Lobakin <alexandr.lobakin@intel.com>
Cc: linux-hardening@vger.kernel.org, x86@kernel.org,
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Subject: Re: [PATCH v8 05/14] x86: conditionally place regular ASM functions
 into separate sections
Message-ID: <20211203163424.GK16608@worktop.programming.kicks-ass.net>
References: <20211202223214.72888-1-alexandr.lobakin@intel.com>
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In-Reply-To: <20211203141051.82467-1-alexandr.lobakin@intel.com>

On Fri, Dec 03, 2021 at 03:10:51PM +0100, Alexander Lobakin wrote:
> From: Peter Zijlstra <peterz@infradead.org>
> Date: Fri, 3 Dec 2021 10:44:10 +0100
> 
> > On Thu, Dec 02, 2021 at 11:32:05PM +0100, Alexander Lobakin wrote:
> > > Use the newly introduces macros to create unique separate sections
> > > for (almost) every "regular" ASM function (i.e. for those which
> > > aren't explicitly put into a specific one).
> > > There should be no leftovers as input .text will be size-asserted
> > > in the LD script generated for FG-KASLR.
> > 
> > *groan*...
> > 
> > Please, can't we do something like:
> > 
> > #define SYM_PUSH_SECTION(name)	\
> > .if section == .text		\
> > .push_section .text.##name	\
> > .else				\
> > .push_section .text		\
> > .endif
> > 
> > #define SYM_POP_SECTION()	\
> > .pop_section
> > 
> > and wrap that inside the existing SYM_FUNC_START*() SYM_FUNC_END()
> > macros.
> 
> Ah I see. I asked about this in my previous mail and you replied
> already (: Cool stuff, I'll use it, it simplifies things a lot.

Note, I've no idea if it works. GAS and me aren't really on speaking
terms. It would be my luck for that to be totally impossible, hjl?