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Date:   Fri, 22 Nov 2019 10:27:54 +0100
From:   Torsten Duwe <duwe@suse.de>
To:     Mark Rutland <mark.rutland@arm.com>
Cc:     linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        Steven Rostedt <rostedt@goodmis.org>,
        Ingo Molnar <mingo@redhat.com>
Subject: Re: KASAN_INLINE && patchable-function-entry
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Hi Mark!

On Thu, 21 Nov 2019 18:36:32 +0000
Mark Rutland <mark.rutland@arm.com> wrote:
[...]
> Was it intended that -fpatachable-function-entry behaved differently
> from -pg in this regard?

No way! I tried to model it as closely as possible along the established
instrumentation mechanism(s).

> Is this likely to be problematic for other users?

I don't think "likely" is the right word here. "rare" would be even
worse. One corner case is more than enough.

> Are there other implicitly-generated functions we need to look out for
> here, for which this would be a problem?
> 
> It looks like this also applies to __attribute__((naked)) on ARM,

IMHO gcc should instrument neither implicitly-generated nor naked
functions in this way. Anybody with reasonable objections please speak
up now.

I'd call it a gcc bug; but it may take a few days...

	Torsten