From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 492C533ADB4; Wed, 17 Dec 2025 09:58:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765965536; cv=none; b=WCkziEOQk3XqXXbcvgs6nFK9oY5am9J4jSOZVT7nAoNkwjqj0cQ98pk9O9Whw0rLKmLRM+RXEVw2CxIuMTrxJYjpnPGUoI3zDSxtPdviemZR6gqsaS3SKtNWSlEbMlvo4792Q8v9A2LCPb9ACJqPfGC8k16vKygRIqc/cXifG7g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765965536; c=relaxed/simple; bh=OATvUezWcwn2SPkaKqyVJ5IFoBchjNJmzx7gvYOlEac=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=UBajAikIMkr9F5VwNZ/iqNwFwvFdW7LiJvvoBj/WenAdHnpdDJaFKMPW9wsdxrLl2f5B0AgkOZalp+c7M//x477mPNax7VmEK+YDoOAf3qTaV4937a2ul4hDP9vz6ZUa2zNVSG8XIqRZrwGN9pVs5L8ciP675uKnnp6bwjUKKFM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 8038C14BF; Wed, 17 Dec 2025 01:58:46 -0800 (PST) Received: from [10.57.47.3] (unknown [10.57.47.3]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 2D2E43F73B; Wed, 17 Dec 2025 01:58:51 -0800 (PST) Message-ID: Date: Wed, 17 Dec 2025 10:58:48 +0100 Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 1/4] selftests/mm: remove flaky header check To: Yunsheng Lin , linux-mm@kvack.org, linux-kselftest@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Andrew Morton , David Hildenbrand , Lorenzo Stoakes , Mark Brown , Ryan Roberts , Shuah Khan , Paolo Abeni References: <20251216142633.2401447-1-kevin.brodsky@arm.com> <20251216142633.2401447-2-kevin.brodsky@arm.com> From: Kevin Brodsky Content-Language: en-GB In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 17/12/2025 04:18, Yunsheng Lin wrote: > On 2025/12/16 22:26, Kevin Brodsky wrote: >> Commit 96ed62ea0298 ("mm: page_frag: fix a compile error when kernel >> is not compiled") introduced a check to avoid attempting to build >> the page_frag module if is missing. >> >> Unfortunately this check only works if KDIR points to >> /lib/modules/... or an in-tree kernel build. It always fails if KDIR >> points to an out-of-tree build (i.e. when the kernel was built with >> O=$KDIR make) because only generated headers are present under >> $KDIR/include/ in that case. >> >> was added more than a year ago (v6.13) so >> we can probably live without that check. > As some commercial OS still uses v6.6, I am wondering if we need that Fair point, I hadn't considered that kselftests are supposed to be buildable against older stable kernels. > check for a little longer, is it possible to do something like below to > avoid the flaky check? > > @@ -46,7 +46,8 @@ CFLAGS += -U_FORTIFY_SOURCE > > KDIR ?= /lib/modules/$(shell uname -r)/build > ifneq (,$(wildcard $(KDIR)/Module.symvers)) > -ifneq (,$(wildcard $(KDIR)/include/linux/page_frag_cache.h)) > +KSRC := $(shell readlink -f $(KDIR)/source 2>/dev/null || echo $(KDIR)) > +ifneq (,$(wildcard $(KSRC)/include/linux/page_frag_cache.h)) > TEST_GEN_MODS_DIR := page_frag > else > PAGE_FRAG_WARNING = "missing page_frag_cache.h, please use a newer kernel" That seems reasonable, and it works for my out-of-tree setup. Will do that in v2, shall I add your Suggested-by, or maybe Co-developed-by? - Kevin