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 868603DFC89; Wed, 25 Mar 2026 15:25:39 +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=1774452339; cv=none; b=nkLedi0fIpl0SZckOiYVP6v/VGDeKVTMZt/ergLRrt7iZ19DMVrJdurfmGDFeOQLhxo7I0K/lV46B0y4NOnw5HxSugnE/SvaDVsSP9zYtJN8+ROkZe7LNaEJdH1wuIJ2gZ7UjQE3SUe2QSjk+6V/aJO8sgSHWOjtOTzn1Yj29D4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774452339; c=relaxed/simple; bh=Bp43AgZh625BebjEYuEfUvU7Z+ABBYjp5XZE++ckXaY=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=gLiXG2c/z7YRo5PhJapJ0f291+7N5EkMelncRlHnP5eWFlsLNh6+7CJ2bMhoWM3dZe9gu31g+cAfKjA63RIAG7BoS9lUgo7L+ngIXhUD+1Y/aLL50/NGx0d/WsAJW56Fjna1C3xo0zYFrR4MlRzvXPhoIgrICSNOC6N5ffsjJQ0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Exb8sdjh; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Exb8sdjh" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B3FFCC4CEF7; Wed, 25 Mar 2026 15:25:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1774452339; bh=Bp43AgZh625BebjEYuEfUvU7Z+ABBYjp5XZE++ckXaY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Exb8sdjh6qbSTeRdnrzcZNx+5lwh/HhjQemU9ifjvf/6/yVrjixTN1xe4Ai5GZtL2 v+xFtbxJsLVV93UclSIQ1EzaJJxqRhuL33aF03sDm4VI0A4ZyRGONhh0x2JosNphi0 1nUX3YQlL70ppLLgO0IQvpl4YdeDaj1BvBWvAJcDvIq4aiQ6ciisv2lcdXPzIGompu IcmX11aU+5UELXxqjog211kwSMPSMsXSoyT77oAj4UqiJswd6tI5Zy9K22ZYBxZ2f3 SZ35nVe6Q0SpRIx4kZqLpwwRNhqB2y1rV3U83UcR1kVmXVwk/YTo+7+GhYW0tNfmuz TwCPiAsFkY5cw== Date: Wed, 25 Mar 2026 16:25:29 +0100 From: Nicolas Schier To: Janne Grunau Cc: Nathan Chancellor , Ahmad Fatoum , Sascha Hauer , Simon Glass , Thomas =?iso-8859-1?Q?Wei=DFschuh?= , linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] kbuild: modules-cpio-pkg: Respect INSTALL_MOD_PATH Message-ID: Mail-Followup-To: Nicolas Schier , Janne Grunau , Nathan Chancellor , Ahmad Fatoum , Sascha Hauer , Simon Glass , Thomas =?iso-8859-1?Q?Wei=DFschuh?= , linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org References: <20260320-kbuild-modules-cpio-pkg-usr-merge-v1-1-cee1ad1bb7cb@jannau.net> <20260325144826.GA2137845@robin.jannau.net> Precedence: bulk X-Mailing-List: linux-kbuild@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260325144826.GA2137845@robin.jannau.net> On Wed, Mar 25, 2026 at 03:48:26PM +0100, Janne Grunau wrote: > On Sat, Mar 21, 2026 at 04:18:46PM +0100, Nicolas Schier wrote: > > On Fri, Mar 20, 2026 at 03:30:32PM +0100, Janne Grunau wrote: > > > The modules-cpio-pkg target added in commit 2a9c8c0b59d3 ("kbuild: add > > > target to build a cpio containing modules") is incompatible with > > > initramfs with merged /lib and /usr/lib directories [1]. "/lib" cannot > > > be a link and directory at the same time. > > > Respect a non-empty INSTALL_MOD_PATH in the modules-cpio-pkg target so > > > that `make INSTALL_MOD_PATH=/usr modules-cpio-pkg` results in the same > > > module install location as `make INSTALL_MOD_PATH=/usr modules_install`. > > > > > > Tested with Fedora distribution initramfs produced by dracut. > > > > > > Link: https://systemd.io/THE_CASE_FOR_THE_USR_MERGE/ [1] > > > Signed-off-by: Janne Grunau > > > --- > > > Hej, > > > > > > this patch allows to produce modules-cpio initramfs which are compatible > > > with initramfs with merged /lib and /usr/lib (/lib as symlink to > > > /usr/lib). I expect initramfs of distributions with merged /usr to have > > > a merged /usr as well. This is at least true for Fedora initramfs built > > > with dracut. > > > > > > I'm not sure whether the trickery to avoid repeated '/' is justified. It > > > is necessary to add a slash between "$@" and a non empty > > > $(INSTALL_MOD_PATH) to avoid make failures due to non existing > > > .tmp_modules_cpio when INSTALL_MOD_PATH without leading slash is used. > > > modules-cpio-pkg`. > > > > > > Better or shorter ways to document this not completely obvious behavior > > > would be appreciated. > > > > > > Janne > > > --- > > > scripts/Makefile.package | 6 ++++-- > > > 1 file changed, 4 insertions(+), 2 deletions(-) > > > > > > diff --git a/scripts/Makefile.package b/scripts/Makefile.package > > > index 0ec946f9b905f74f8698d8d6967d22f5b76f64e0..ab18cf81622ae319380528c401f9aeb6d32070c6 100644 > > > --- a/scripts/Makefile.package > > > +++ b/scripts/Makefile.package > > > @@ -195,7 +195,9 @@ tar%-pkg: linux-$(KERNELRELEASE)-$(ARCH).tar.% FORCE > > > .tmp_modules_cpio: FORCE > > > $(Q)$(MAKE) -f $(srctree)/Makefile > > > $(Q)rm -rf $@ > > > - $(Q)$(MAKE) -f $(srctree)/Makefile INSTALL_MOD_PATH=$@ modules_install > > > + $(Q)$(MAKE) -f $(srctree)/Makefile \ > > > + INSTALL_MOD_PATH=$@$(if $(INSTALL_MOD_PATH),/$(INSTALL_MOD_PATH:/%=%)) \ > > > + modules_install > > > > Thanks for the patch along with its detailed description! > > > > For completeness: I'd rather use $(addprefix): > > > > INSTALL_MOD_PATH=$@$(addprefix /,$(INSTALL_MOD_PATH:/%=%)) > > > > but as POSIX states: > > > > | Multiple successive characters are considered to be the same > > | as one , except it is implementation-defined whether the case > > | of exactly two leading characters is treated specially. > > https://pubs.opengroup.org/onlinepubs/9799919799.2024edition/ > > argh, I did read this but confused myself by the second part to think it > was only for leading slashes. :) you are by far not the only one who gets confused by that. -- Nicolas