From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8F210C433DB for ; Mon, 8 Feb 2021 18:27:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3DE8064E6D for ; Mon, 8 Feb 2021 18:27:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232499AbhBHS1I (ORCPT ); Mon, 8 Feb 2021 13:27:08 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37322 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235621AbhBHS0R (ORCPT ); Mon, 8 Feb 2021 13:26:17 -0500 Received: from sipsolutions.net (s3.sipsolutions.net [IPv6:2a01:4f8:191:4433::2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0FF44C061786; Mon, 8 Feb 2021 10:25:31 -0800 (PST) Received: by sipsolutions.net with esmtpsa (TLS1.3:ECDHE_SECP256R1__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.94) (envelope-from ) id 1l9BDz-000AHc-Jg; Mon, 08 Feb 2021 19:25:27 +0100 Message-ID: <69e7fbb93740c0116c358a2f40aadb2dbde702fe.camel@sipsolutions.net> Subject: Re: [PATCH AUTOSEL 4.9 4/4] init/gcov: allow CONFIG_CONSTRUCTORS on UML to fix module gcov From: Johannes Berg To: Sasha Levin , "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" Cc: Peter Oberparleiter , Arnd Bergmann , Jessica Yu , Andrew Morton , Linus Torvalds Date: Mon, 08 Feb 2021 19:25:21 +0100 In-Reply-To: <20210208180000.2092497-4-sashal@kernel.org> References: <20210208180000.2092497-1-sashal@kernel.org> <20210208180000.2092497-4-sashal@kernel.org> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.36.5 (3.36.5-2.fc32) MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-malware-bazaar: not-scanned Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Mon, 2021-02-08 at 18:00 +0000, Sasha Levin wrote: > From: Johannes Berg > > [ Upstream commit 55b6f763d8bcb5546997933105d66d3e6b080e6a ] > > On ARCH=um, loading a module doesn't result in its constructors getting > called, which breaks module gcov since the debugfs files are never > registered. On the other hand, in-kernel constructors have already been > called by the dynamic linker, so we can't call them again. > > Get out of this conundrum by allowing CONFIG_CONSTRUCTORS to be > selected, but avoiding the in-kernel constructor calls. > > Also remove the "if !UML" from GCOV selecting CONSTRUCTORS now, since we > really do want CONSTRUCTORS, just not kernel binary ones. > > Link: https://lkml.kernel.org/r/20210120172041.c246a2cac2fb.I1358f584b76f1898373adfed77f4462c8705b736@changeid > While I don't really *object* to this getting backported, it's also a (development) corner case that somebody wants gcov and modules in ARCH=um ... I'd probably not backport this. johannes