From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail1.nippynetworks.com (mail1.nippynetworks.com [91.220.24.129]) (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 9390C2C326B for ; Tue, 17 Feb 2026 19:27:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.220.24.129 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771356464; cv=none; b=FzWd2HN36GXLhFC8mGgj6BbS6AOt+xWpwRe3RGbjisGiFnjYLbE7rR662xYelFUQ3ba2qnUiDbepkV0FKjQ8jdP0C70fcr1hd31crcY6M6ZZsDQqRDRJFfyxN4skMJz2xZka3S9mlC4hU7+kpojma9HUkstVc+9VCOn2bzTwRC8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771356464; c=relaxed/simple; bh=6ahUERcjA1hQD5QS68+Na6XAuwMNnMut354TTO8f+/w=; h=Message-ID:Date:MIME-Version:From:To:Subject:Content-Type; b=sTP5F66lNAOxK2kAnvSgpYuwLvKSZSuNTH1tf/35QRZ04kx7MUQr531V9eNb7bpQsNpdRG5tB9CmgvThGjJCrb+lXb+wRkmQuLePmp3E1UYxUnCmMnzCRPtn0cb84u14lmNNmV6e/Hns8t3UPK/uvtgUhH9tK8nCojwDmWgVh8s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=wildgooses.com; spf=pass smtp.mailfrom=wildgooses.com; dkim=pass (1024-bit key) header.d=wildgooses.com header.i=@wildgooses.com header.b=WeVdClFU; arc=none smtp.client-ip=91.220.24.129 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=wildgooses.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=wildgooses.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=wildgooses.com header.i=@wildgooses.com header.b="WeVdClFU" Received: from [192.168.105.108] (unknown [212.69.38.73]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature ECDSA (P-256) server-digest SHA256) (No client certificate requested) (Authenticated sender: ed@wildgooses.com) by mail1.nippynetworks.com (Postfix) with ESMTPSA id 4fFqMm6YHMzkk60; Tue, 17 Feb 2026 19:24:36 +0000 (GMT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=wildgooses.com; s=dkim; t=1771356277; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=6ahUERcjA1hQD5QS68+Na6XAuwMNnMut354TTO8f+/w=; b=WeVdClFU8oo5uKDoh8VTdm2HKfRmTiTmczezGI9GJcI4bTUEmJ7D/56X+A9DxXVDr6BUyx zCxv4By+fslm9jwPWquZvoR9tA2+N/aHOK+/1SMexRSgyzsS+FM8Uru1y5ocPC5yx2Gb2x 5nwV3iNtZesHYJcoGzjEpMJfw9XGsIQ= Message-ID: <587f25e0-a80e-46a5-9f01-87cb40cfa377@wildgooses.com> Date: Tue, 17 Feb 2026 19:24:36 +0000 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird From: Ed W Content-Language: en-GB To: Linux Kernel Mailing List , masahiroy@kernel.org, nathan@kernel.org Subject: extlinux can't boot kernel after commit "kbuild: keep .modinfo section in vmlinux.unstripped" Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Hi, I wonder if I can get some help debugging a problem post the followin= g commit. After trying to upgrade to a newer kernel build I encountered boot failures on my amd64 m= achine, booting via extlinux and git bisect narrowed it down to this commit: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?= h=3Dv6.19.2&id=3D3e86e4d74c0490e5fc5a7f8de8f29e7579c9ffe5 kbuild: keep .modinfo section in vmlinux.unstripped Keep the .modinfo section during linking, but strip it from the final vml= inux.=C2=A0 Adjust scripts/mksysmap to exclude modinfo symbols from kallsyms.=C2=A0 This change will allow the next commit to extract the .modinfo section fr= om the vmlinux.unstripped intermediate. The symptoms are that prior to this commit I can boot a kernel built usin= g gcc-15 and binutils 2.45.1, however, adding that commit, or trying kernels up to 6.18.12, all= fail to boot the bzImage file. =C2=A0 Extlinux apparently won't read (or otherwise rejects as invalid) the resu= lting bzImage kernel with error: =C2=A0 =C2=A0 failed: I/O error So it doesn't even try to run the kernel, it appears to fail reading from= disk (and presumably locating the entry point for execution?) Kernel is relocatable and hence ends up being built with=C2=A0 VMLINUX_NEEDS_RELOCS=3Dy Curiously, if I build with clang then the resulting kernels all seem to w= ork without a problem?? System is one of a cluster of Ryzen 9 5950X, but similar errors appear wi= th older Ryzen 9 3900 boxes. Underlying OS is gentoo, so packages approximately as per latest r= eleases with that. I'm not sure how to narrow down what precisely triggers the boot failure = though. For example I see similar results to the following on both a working 6.17.0 and a broken 6.= 18.12 # readelf -l vmlinux | grep -A3 LOAD =C2=A0 LOAD=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A00x0000000000200000 0x= ffffffff81000000 0x0000000001000000 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A00x000000000= 2a8b4d0 0x0000000002a8b4d0=C2=A0 R E=C2=A0 =C2=A0 0x200000 =C2=A0 LOAD=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A00x0000000002e00000 0x= ffffffff83c00000 0x0000000003c00000 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A00x000000000= 1a00000 0x0000000001a00000=C2=A0 RW=C2=A0 =C2=A0 =C2=A00x200000 =C2=A0 NOTE=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A00x0000000002c8b47c 0x= ffffffff83a8b47c 0x0000000003a8b47c =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A00x000000000= 0000054 0x0000000000000054=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A00x4 On the non working 6.18.12 I see: # readelf -S vmlinux.unstripped | grep modinfo =C2=A0 [70] .modinfo=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 PROGBITS=C2=A0 =C2= =A0 =C2=A0 =C2=A0 =C2=A0ffffffff85600000=C2=A0 04800000 # readelf -S vmlinux | grep modinfo So it seems as though the modinfo sectors ARE being stripped?! My guess is that something has moved or become re-ordered such that the e= xtlinux is rejecting the image??=C2=A0 At this point I'm honestly not quite sure what I am doing, so would some = kind soul please help me figure out what is happening? I apologise in advance that I've likely not= given enough information about the problem, please be gentle... Ed W