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Date: Wed, 11 Mar 2026 23:57:17 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Jann Horn <jannh@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>,
	Andrey Konovalov <andreyknvl@gmail.com>,
	Nathan Chancellor <nathan@kernel.org>,
	Nick Desaulniers <nick.desaulniers+lkml@gmail.com>,
	Bill Wendling <morbo@google.com>,
	Justin Stitt <justinstitt@google.com>, linux-kernel@vger.kernel.org,
	kasan-dev@googlegroups.com, llvm@lists.linux.dev,
	Ingo Molnar <mingo@redhat.com>,
	Josh Poimboeuf <jpoimboe@kernel.org>
Subject: Re: [PATCH 0/3] KCOV function entry/exit records
Message-ID: <20260311225717.GY606826@noisy.programming.kicks-ass.net>
References: <20260311-kcov-extrecord-v1-0-68f03c4a05ad@google.com>
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In-Reply-To: <20260311-kcov-extrecord-v1-0-68f03c4a05ad@google.com>

On Wed, Mar 11, 2026 at 10:06:13PM +0100, Jann Horn wrote:
> This series adds a KCOV feature that userspace can use to keep track of
> the current call stack. When userspace enables the new mode
> KCOV_TRACE_PC_EXT, collected instruction addresses are tagged with one
> of three types:
> 
>  - function entry
>  - non-entry basic block
>  - function exit
> 
> This requires corresponding LLVM support; an LLVM patch implementing
> this feature has been uploaded for review at
> <https://github.com/llvm/llvm-project/pull/185972>, but hasn't landed yet.

And I don't suppose KCOV will finally honour noinstr ?