From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 65AC9267F65; Tue, 8 Apr 2025 11:27:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744111652; cv=none; b=K4AnCADpDtE3BYL8Fxzvl3W1nBvn42dt0+mvFjOBXYH4PSHAmDozT8PWsgakg/+cFNHGFXT5j4FCEL6bEfpALdetLMWvmwzukCZ91U04IOEL30adak3cVjbVSbtzOSiZRAU9WKT9psGvppV4v38aU3ssbLZKiXg1Z7Kz2G53PWA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744111652; c=relaxed/simple; bh=O6K/vQLIyU7g0e0FWCrR6jYFew9AAvx95OGynDYTEnk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=QD7jl2oPoRs3hVSux9IT0IFwYPOE+H3onptKWkjVhYT76J4Z93bPN70xwMpZNVl5XRZceVvCHnbhH5M+vAxdMRnK8imxqWtlr8XZaXibGANpwRGDfknZHg+vvV0eethFJ3eF5tSl4ci33Ep8SBDbK8Sst//+Npe1PDlwrmbLnYI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=smxVv0D1; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="smxVv0D1" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B598EC4CEEE; Tue, 8 Apr 2025 11:27:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1744111652; bh=O6K/vQLIyU7g0e0FWCrR6jYFew9AAvx95OGynDYTEnk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=smxVv0D1cHzjcnoEthej+3UORa/2fc22dAflG/ISIHWm25PVn84Tc3A3Defo3TOqK JEbIJEHJAA0Wo5xISGgTM2My81DN9g0yaQOTGiM96M3ClWpMwiWc1+ZrPmzEgXmgk+ E1mvczMaqPFQ0SEn0EKAto333uDvvBTmRJQOGhhQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Luca Ceresoli , Charlie Jenkins , Namhyung Kim , Sasha Levin Subject: [PATCH 6.14 469/731] perf build: Fix in-tree build due to symbolic link Date: Tue, 8 Apr 2025 12:46:06 +0200 Message-ID: <20250408104925.187914198@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250408104914.247897328@linuxfoundation.org> References: <20250408104914.247897328@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Luca Ceresoli [ Upstream commit 75100d848ef4b8ca39bb6dd3a21181e37dea27e2 ] Building perf in-tree is broken after commit 890a1961c812 ("perf tools: Create source symlink in perf object dir") which added a 'source' symlink in the output dir pointing to the source dir. With in-tree builds, the added 'SOURCE = ...' line is executed multiple times (I observed 2 during the build plus 2 during installation). This is a minor inefficiency, in theory not harmful because symlink creation is assumed to be idempotent. But it is not. Considering with in-tree builds: srctree=/absolute/path/to/linux OUTPUT=/absolute/path/to/linux/tools/perf here's what happens: 1. ln -sf $(srctree)/tools/perf $(OUTPUT)/source -> creates /absolute/path/to/linux/tools/perf/source link to /absolute/path/to/linux/tools/perf => OK, that's what was intended 2. ln -sf $(srctree)/tools/perf $(OUTPUT)/source # same command as 1 -> creates /absolute/path/to/linux/tools/perf/perf link to /absolute/path/to/linux/tools/perf => Not what was intended, not idempotent 3. Now the build _should_ create the 'perf' executable, but it fails The reason is the tricky 'ln' command line. At the first invocation 'ln' uses the 1st form: ln [OPTION]... [-T] TARGET LINK_NAME and creates a link to TARGET *called LINK_NAME*. At the second invocation $(OUTPUT)/source exists, so 'ln' uses the 3rd form: ln [OPTION]... TARGET... DIRECTORY and creates a link to TARGET *called TARGET* inside DIRECTORY. Fix by adding -n/--no-dereference to "treat LINK_NAME as a normal file if it is a symbolic link to a directory", as the manpage says. Closes: https://lore.kernel.org/all/20241125182506.38af9907@booty/ Fixes: 890a1961c812 ("perf tools: Create source symlink in perf object dir") Signed-off-by: Luca Ceresoli Reviewed-by: Charlie Jenkins Tested-by: Charlie Jenkins Link: https://lore.kernel.org/r/20250124-perf-fix-intree-build-v1-1-485dd7a855e4@bootlin.com Signed-off-by: Namhyung Kim Signed-off-by: Sasha Levin --- tools/perf/Makefile.perf | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf index 05c083bb11220..eea8877c7cba3 100644 --- a/tools/perf/Makefile.perf +++ b/tools/perf/Makefile.perf @@ -158,7 +158,7 @@ ifneq ($(OUTPUT),) VPATH += $(OUTPUT) export VPATH # create symlink to the original source -SOURCE := $(shell ln -sf $(srctree)/tools/perf $(OUTPUT)/source) +SOURCE := $(shell ln -sfn $(srctree)/tools/perf $(OUTPUT)/source) endif # Do not use make's built-in rules -- 2.39.5