From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AD30837D12E; Mon, 14 Sep 2026 09:32:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789378368; cv=none; b=tl4ZbUm+va7vqIXBwUvZHmAl/FR+rzPoOWOpykCDjbPoABkeSE2MyxJtjNlkXFHoveuAbTw+oJIR94vWgRGhcZkg7gn0lZlYkOQRdLqW8W2wPtF8SL8cYCWn1kwPuXXdTo9nbGtWOB2wJkPKofnFODYLjwciKtycVXw500npFY0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789378368; c=relaxed/simple; bh=EGGLwfkvC/bmmdRr9joHnUFtlfZrZE1gg7U1RgrGHAE=; h=From:Subject:To:Cc:In-Reply-To:References:Content-Type:Date: Message-Id; b=I1WWfbd3ZANxKRvQMp9T8iX/phs0S37tcckPw+Zt+F2qSJQndMT105RkS20ZEExWaP4XdNWzbwQ784AXrCxQDvyi/tiWTKdT1BinHCjWOvHWTW1eVee84j9R+V46/4pMO+9TUNBUcoOCuCpVrCDdD4+d1CWrXDYfXhh5ml8DOZo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Th8wHv4J; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Th8wHv4J" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 661861F000FF; Mon, 14 Sep 2026 09:32:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789378367; bh=EGGLwfkvC/bmmdRr9joHnUFtlfZrZE1gg7U1RgrGHAE=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=Th8wHv4JNNKzyrlYUql3b+BYne0/udn0j0EUsxiSV3CUGcDnitBFbPjFP2Rj7e0qy rFT48xpZcwuFEn5DsHs2Fs3fgOLQCSmes7/uuTWxP4lh+lwWd6I12d9dmOsOgS/+WJ yCAotq4osVaMMdyeA+HgeOw4C5VsIl1hgVKEFKjKtRFaMIhScNU66sQw26n/BIXlUp drF60/ndtDPpi94lAFkqn8zIhdkqZszn97XsCNpa4d0+utIFCHTIUKsYFnp+hPv3hI 3NmVkW8p0TNTBx+wOIoD/Z0XoOOmBb+MyUaqzKNuuR5VsNV/ottLU5ZN95Cf18sZ6Z TM/8O7gCfw57w== From: sashiko-bot@kernel.org Subject: Re: [PATCH v6 2/7] riscv: stacktrace: disable KASAN and KCOV instrumentation for stacktrace.o Reply-To: sashiko-reviews@lists.linux.dev To: "Shuai Xue" Cc: linux-perf-users@vger.kernel.org, linux-trace-kernel@vger.kernel.org In-Reply-To: <20260914092648.51254-3-xueshuai@linux.alibaba.com> References: <20260914092648.51254-1-xueshuai@linux.alibaba.com> <20260914092648.51254-3-xueshuai@linux.alibaba.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Mon, 14 Sep 2026 09:32:46 +0000 Message-Id: <20260914093247.661861F000FF@smtp.kernel.org> Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: > From: Wang Han >=20 > KASAN records stack traces for every alloc/free, which means it walks > the unwinder very frequently. Instrumenting the stack trace collection > code itself adds substantial overhead and makes the traces themselves > noisier. >=20 > KCOV instruments every basic-block edge. The unwinder is a hot path, > especially with KASAN enabled, so KCOV instrumentation has the same kind > of cost and noise problem here. >=20 > Mark stacktrace.o as not KASAN- or KCOV-instrumented, matching the x86 > treatment of its stack unwinding code. RISC-V keeps the relevant unwinder > code in stacktrace.o, so a single translation-unit annotation covers the > equivalent scope. This is a prerequisite preference for the upcoming > reliable unwinder, but the change is valid on its own. >=20 > Reviewed-by: Shuai Xue > Assisted-by: Qoder:Qwen-3.8-MAX-Preview > Signed-off-by: Wang Han > Signed-off-by: Shuai Xue Sashiko has reviewed this patch and found no issues. It looks great! --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20260914092648.5125= 4-1-xueshuai@linux.alibaba.com?part=3D2