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 35BDA248F7D; Tue, 16 Sep 2025 13:03:51 +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=1758027833; cv=none; b=Cvs4zv2C1Z7T4vN71MldVUQiNDyyBXWn67D18wB7pNNzbTH/DB9vNYp4GGjK5MMsBy1WXMpTW/E/xI1+rRkGNWETk12tCxANsXmb7TYYGhEaX+1mdcUgqxGL7rDkeuRybBx83XYiYItmR5I1qar4VRIULihagTbJEulEUqZgFMk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758027833; c=relaxed/simple; bh=xlae1wF0J130jtwg6EYfQcFhZjLwjiRFyW9NKgHZCAM=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=u+kLiWxlge6jbVHEDn71R4aBiFdZ94lhw98W1Iv5VdliYDk+RNiqAu7/mggpcEjckDrDAQIYm4uaMFW097yqIw3GTGtGAbsqb+zwO8uORnd7YdIK6bZKcs6Ln+pHriJJKOArQEETsSspQz00R4ZZE/5EGZIdDP5XFQ9mAA8nWUY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=lmRzLJuu; 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="lmRzLJuu" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 98E22C4CEEB; Tue, 16 Sep 2025 13:03:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1758027831; bh=xlae1wF0J130jtwg6EYfQcFhZjLwjiRFyW9NKgHZCAM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=lmRzLJuuhcwEe47TwLrX3dZEjy6Fyv1PHIAJbIjgd4V+mQeBkIYkg29UspxuCVvDB AcWbozXEYCGq5Iuk+7JKShUkRSfcJujoDjV5MGivkbC7v4sJ9Wt4OuBqZJNGopAs8M TJImjIQSHYxsWudqCRI2Jd/dHXEgoNxazg8LKkL71EfAa84fNJKPxp4H8B5Up43tFI PdLDLQcSqyPnAfkQ1m3zQDk7iMKd+S7+b35H/GCGSqq/UdeA2XcBLehBLxe4PoMZnE CjP8v/5VvQ+qNXZAkV5SRknrMSMOEkq5WyUfvGX5cgAHMnw3NKAG5mhjKFhLXMcoaS BE3gckgYx2y9Q== Date: Tue, 16 Sep 2025 15:03:46 +0200 From: Alexey Gladkov To: Nicolas Schier Cc: Nathan Chancellor , Petr Pavlu , Luis Chamberlain , Sami Tolvanen , Daniel Gomez , linux-kernel@vger.kernel.org, linux-modules@vger.kernel.org, linux-kbuild@vger.kernel.org, Masahiro Yamada Subject: Re: [PATCH v7 3/8] kbuild: keep .modinfo section in vmlinux.unstripped Message-ID: References: <4d53c72293d88b663257a0d723ebf3473a08b374.1755535876.git.legion@kernel.org> Precedence: bulk X-Mailing-List: linux-modules@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: On Tue, Sep 16, 2025 at 02:42:48PM +0200, Nicolas Schier wrote: > > > > > Hi Alexey, > > > > > > > > > > with this patch applied, I still get a warning from objcpy as Masahiro > > > > > and Stephen wrote [1,2] > > > > > > > > > > SORTTAB vmlinux.unstripped > > > > > + sorttable vmlinux.unstripped > > > > > + nm -S vmlinux.unstripped > > > > > + ./scripts/sorttable -s .tmp_vmlinux.nm-sort vmlinux.unstripped > > > > > + is_enabled CONFIG_KALLSYMS > > > > > + grep -q ^CONFIG_KALLSYMS=y include/config/auto.conf > > > > > + cmp -s System.map .tmp_vmlinux2.syms > > > > > + echo vmlinux.unstripped: ../scripts/link-vmlinux.sh > > > > > # OBJCOPY vmlinux > > > > > objcopy --remove-section=.modinfo vmlinux.unstripped vmlinux > > > > > objcopy: vmlinux.unstripped: warning: empty loadable segment detected at vaddr=0xffff8000807a0000, is this intentional? > > > > > > > > > > (arm64, allnoconfig) > > > > > > > > > > Kind regards, > > > > > Nicolas > > > > > > > > > > > > > > > [1]: https://lore.kernel.org/linux-kbuild/CAK7LNAR-gD2H6Kk-rZjo0R3weTHCGTm0a=u2tRH1WWW6Sx6=RQ@mail.gmail.com/ > > > > > [2]: https://lore.kernel.org/lkml/20250730164047.7c4a731a@canb.auug.org.au/ > > > > > > > > > > > > > Hm. I missed that. I need to investigate how to fix this. Nothing comes > > > > to mind right now. > > > > > > Same here. Only thing I could find until now is > > > > > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/diff/scripts/link-vmlinux.sh?id=90ceddcb495008ac8ba7a3dce297841efcd7d584 > > > > > > where '2>/dev/null' is appended exactly to prevent this very warning. > > > But for me, it doesn't feel good doing that when stripping to vmlinux. > > > > Yes, that's not a very good approach. It will hide other errors that will > > definitely need to be seen. I think the commit you mentioned is actually > > incorrect. I think there should be a different solution. > > > > I think in the case of .modinfo, we can change the flag in the section > > since we are going to delete it anyway. > > > > diff --git a/scripts/Makefile.vmlinux b/scripts/Makefile.vmlinux > > index dbbe3bf0cf23..9a118b31d0dc 100644 > > --- a/scripts/Makefile.vmlinux > > +++ b/scripts/Makefile.vmlinux > > @@ -87,7 +87,8 @@ remove-section-$(CONFIG_ARCH_VMLINUX_NEEDS_RELOCS) += '.rel*' > > remove-symbols := -w --strip-symbol='__mod_device_table__*' > > > > quiet_cmd_strip_relocs = OBJCOPY $@ > > - cmd_strip_relocs = $(OBJCOPY) $(addprefix --remove-section=,$(remove-section-y)) \ > > + cmd_strip_relocs = $(OBJCOPY) $(patsubst %,--set-section-flags %=noload,$(remove-section-y)) $< && \ > > + $(OBJCOPY) $(addprefix --remove-section=,$(remove-section-y)) \ > > $(remove-symbols) $< $@ > > > > targets += vmlinux > > Ah, great! I thought we had to fiddle around with linker scripts et al. > I needed to use an intermediate file: > > diff --git a/scripts/Makefile.vmlinux b/scripts/Makefile.vmlinux > index e2ceeb9e168d..516d51ca634b 100644 > --- a/scripts/Makefile.vmlinux > +++ b/scripts/Makefile.vmlinux > @@ -90,6 +90,9 @@ remove-section-y := .modinfo > remove-section-$(CONFIG_ARCH_VMLINUX_NEEDS_RELOCS) += '.rel*' > > quiet_cmd_strip_relocs = OBJCOPY $@ > - cmd_strip_relocs = $(OBJCOPY) $(addprefix --remove-section=,$(remove-section-y)) $< $@ > + cmd_strip_relocs = set -e; \ > + trap 'rm $<.noload' EXIT HUP INT; \ > + $(OBJCOPY) $(patsubst %,--set-section-flags %=noload,$(remove-section-y)) $< $<.noload && \ > + $(OBJCOPY) $(addprefix --remove-section=,$(remove-section-y)) $<.noload $@ > > targets += vmlinux according to man-page: If you do not specify outfile, objcopy creates a temporary file and destructively renames the result with the name of infile. That is true even in freebsd: https://man.freebsd.org/cgi/man.cgi?query=objcopy Do you want to support any other objcopy implementations ? -- Rgrds, legion