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Tue, 6 Oct 2026 11:14:43 -0400 (EDT) X-Mailer: MessagingEngine.com Webmail Interface Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ThreadId: A8p1gvDKPv03 Date: Tue, 06 Oct 2026 15:14:23 +0000 From: "Chuck Wolber" To: kasan-dev@googlegroups.com, nathan@kernel.org, akpm@linux-foundation.org, anton.ivanov@cambridgegreys.com, oberpar@linux.ibm.com, ardb@kernel.org, arnd@arndb.de, bhelgaas@google.com, bp@alien8.de, dave.hansen@linux.intel.com, dvyukov@google.com, hpa@zytor.com, jinghao7@illinois.edu, johannes@sipsolutions.net, jpoimboe@kernel.org, justinstitt@google.com, kees@kernel.org, kent.overstreet@linux.dev, linux-arch@vger.kernel.org, linux-efi@vger.kernel.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-um@lists.infradead.org, llvm@lists.linux.dev, luto@kernel.org, marinov@illinois.edu, masahiroy@kernel.org, maskray@google.com, mathieu.desnoyers@efficios.com, mhiramat@kernel.org, mingo@redhat.com, morbo@google.com, ndesaulniers@google.com, paulmck@kernel.org, richard@nod.at, rostedt@goodmis.org, samitolvanen@google.com, tglx@linutronix.de, tingxur@illinois.edu, tyxu@illinois.edu, wentaoz5@illinois.edu, x86@kernel.org, peterz@infradead.org, sashal@kernel.org, elver@google.com Message-Id: <00ed0b57-ad05-4c5d-b152-7c81df94b23a@app.fastmail.com> Subject: [PROPOSAL] Replace gcov and kcov with llvm-cov Content-Type: text/plain Content-Transfer-Encoding: 7bit Stemming from some hallway track conversations with maintainers at LPC 2026, I propose replacing gcov and kcov in the kernel with llvm-cov. llvm-cov instruments at the AST which enables precise mapping back to source code regardless of optimization level. We have a set of patches [1] that implements kernel based llvm-cov. They need to be updated and some additional patches are required to address some stubs that are missing noinstr annotation. But otherwise I should be able to send a full set of patches (including taking on the maintainer role) to remove gcov and kcov and replace it with llvm-cov in fairly short order. If there is a desire to take this in pieces or implement other intermediate steps, let me know. Otherwise I can generate a monolithic set all at once. [1] https://lore.kernel.org/lkml/20240905043245.1389509-1-wentaoz5@illinois.edu/ Thank you, ..Ch:W..