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 B94943B102F for ; Tue, 23 Jun 2026 21:46:56 +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=1782251218; cv=none; b=mpJDJEMTjJZXKzqgZIbdxkqefpj/NOpaVg0qzGqqRWIOIAz00M5O0ZE5zdpp4idyVc1kTi/nXC+D9DllpRAC27W+TZjbcvz0mj8V9PbLR0BeSjLfQeGnO/l6IXyueLdZZwWFOIuMTSArw0v/mWrJIAamZgx1WpkHcSs7iL3sBQs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782251218; c=relaxed/simple; bh=JXgxWQa95XIvCphWzvEbtA6e/RopWT1PDUGRYNBthcg=; h=From:Subject:To:Cc:In-Reply-To:References:Content-Type:Date: Message-Id; b=tmZpLb9zJlrjzv3zdW3odWuX8hheelPgVmtHNBNRAcTqp/BQME1/814NAJ3uVQUkgtvY5uVRnLr8BAoD+8fVtUOJoKVj50EoTM8Y1nlMyZixFZ2IMsQXzzo7uh+4xxYim99Tn3/WKlOBJ5GpBwvtvf1ZNGf82+Npvxf+Jroohc8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ISiS3b88; 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="ISiS3b88" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E522E1F000E9; Tue, 23 Jun 2026 21:46:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1782251216; bh=NliGj/nFWfb+7WeHEeLqJHTzSUW6uWRjKDfqfFfHw6I=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=ISiS3b889cicbswXQHPYWZfSGeeArOnWkAoje0RaPZnGJZFPIx7cG0pidERABlQ4P dsrA9QbvPSMMEBBk8d6RIDI1W0BT1nnTaUVIzexmps6ghcR862ABy2FcU4aWZZM/YW iohJU1a/ZBa39wu15e90bifPNB/dF9jywcj/lZOmpACWNJ9R0Kl3pzKOSCW86/fw49 DLvZJbVu2dxrHM/Jh0O1XQZddSL+UV+UtvGIHCqpPibTXXk1WzepBE+s4pXNH/e5Oi DqP9I26eDk7VZlLvZ3Pd+1MwQF1F+Ftt2rVtrtvirUrCZSgsEUq6NqI/LKxn+Cc7ej 7mh0zwFoaFz/A== From: sashiko-bot@kernel.org Subject: Re: [PATCH v2 4/6] perf kvm: Do not copy filename string Reply-To: sashiko-reviews@lists.linux.dev To: "Namhyung Kim" Cc: linux-perf-users@vger.kernel.org In-Reply-To: <20260623191439.3621593-5-namhyung@kernel.org> References: <20260623191439.3621593-1-namhyung@kernel.org> <20260623191439.3621593-5-namhyung@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Tue, 23 Jun 2026 21:46:55 +0000 Message-Id: <20260623214655.E522E1F000E9@smtp.kernel.org> Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Thank you for your contribution! Sashiko AI review found 1 potential issue(= s) to consider: - [Low] The error checking logic for `get_filename_for_perf_kvm()` is unrea= chable dead code. -- commit 0b8de0bac81d07f5d9beff7d22b8144187910bab Author: Namhyung Kim perf kvm: Do not copy filename string As it removed STRDUP_FAIL_EXIT(), it no longer calls free() for elements in the copied argv. Thus, the filename should not be allocated as well. In fact, it's a pointer to string literals and should be fine to pass the pointer. > diff --git a/tools/perf/builtin-kvm.c b/tools/perf/builtin-kvm.c > index 278543ca66a37..021af3c64acd0 100644 > --- a/tools/perf/builtin-kvm.c > +++ b/tools/perf/builtin-kvm.c > @@ -607,11 +607,11 @@ static const char *get_filename_for_perf_kvm(void) > const char *filename; > =20 > if (perf_host && !perf_guest) > - filename =3D strdup("perf.data.host"); > + filename =3D "perf.data.host"; > else if (!perf_host && perf_guest) > - filename =3D strdup("perf.data.guest"); > + filename =3D "perf.data.guest"; > else > - filename =3D strdup("perf.data.kvm"); > + filename =3D "perf.data.kvm"; > =20 > return filename; > } [Severity: Low] Does this change leave unreachable dead code in cmd_kvm()? Now that get_filename_for_perf_kvm() returns static string literals, it can never return NULL. However, its caller cmd_kvm() still checks for NULL and returns -ENOMEM: if (!file_name) { file_name =3D get_filename_for_perf_kvm(); if (!file_name) { pr_err("Failed to allocate memory for filename\n"); return -ENOMEM; } } Is it okay to clean up the redundant NULL check and error message from cmd_kvm() since this allocation failure is no longer possible? --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20260623191439.3621= 593-1-namhyung@kernel.org?part=3D4