From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out30-97.freemail.mail.aliyun.com (out30-97.freemail.mail.aliyun.com [115.124.30.97]) (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 ACB5D233713 for ; Tue, 8 Jul 2025 15:32:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.97 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751988732; cv=none; b=fPOsj3L+uml4eDCECg5zOsvvj14K2Jiau5kq6HzRFi27ETTzz0ylS8dGLCD6XbYcsETFEDhE9NZfNjSVGd1lf3ua0UJDloRIZ1w2YGDwhYedxqwR7rK/dh5XpY++TvVfMtE5m+1PD92rHCTDyumuLWHx1eleaYfPaC+2Z/+MVKw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751988732; c=relaxed/simple; bh=/wv1ujVVYsKxfD9Gx4YbkGRQTRO9miJk819wGwlJTuQ=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=Cx6wcsnX/XEmwR6pdcQBQvOQZHcBYlbCNFBETZXGRHDzXOLRJLIv3HcpYl/xnAisXVM9Dn6iRgbrelkyYLtRM/ZEN8Dse/M3e+e0N8pdlZr0LnB9znNXSY9CxgDUqerlJlmtVjY9jAR+K00KFMU/AeW8LrSdtiahJwy3K7isah0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=tBmnK4KD; arc=none smtp.client-ip=115.124.30.97 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="tBmnK4KD" DKIM-Signature:v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1751988726; h=Message-ID:Date:MIME-Version:Subject:To:From:Content-Type; bh=EeG7VhJ+3VL+xoKGwYSETtPL5tcP8qm4ksM/Bn5qQkg=; b=tBmnK4KDH636pBRDuHr9aNhj5NP9hTS7VRSodi/5kFhl0Ik5tH0xLK4R1+x7N7Ux+oxPq414uVHqE8DzkXtmTxeY/TxsZNRAomPO+Xqpwn4So1HSu7KA/x87SL1W+SYXPU/0VQtipJxmtILVDWtRcf8ZV31nLJ7O84oUysMlpmU= Received: from 30.170.233.0(mailfrom:hsiangkao@linux.alibaba.com fp:SMTPD_---0WiPlTZ4_1751988724 cluster:ay36) by smtp.aliyun-inc.com; Tue, 08 Jul 2025 23:32:05 +0800 Message-ID: <6216008a-dc0c-4f90-a67c-36bead99d7f2@linux.alibaba.com> Date: Tue, 8 Jul 2025 23:32:03 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: Executable loading issues with erofs on arm? To: Jan Kiszka , Gao Xiang , Chao Yu , linux-erofs@lists.ozlabs.org Cc: Linux Kernel Mailing List References: <38d43fae-1182-4155-9c5b-ffc7382d9917@siemens.com> <452a2155-ab3b-43d1-8783-0f1db13a675f@siemens.com> <81a3d28b-4570-4d44-8ed6-51158353c0ff@siemens.com> From: Gao Xiang In-Reply-To: <81a3d28b-4570-4d44-8ed6-51158353c0ff@siemens.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 2025/7/8 23:22, Jan Kiszka wrote: > On 08.07.25 17:12, Gao Xiang wrote: >> Hi Jan, >> >> On 2025/7/8 20:43, Jan Kiszka wrote: >>> On 08.07.25 14:41, Jan Kiszka wrote: >>>> Hi all, >>>> >>>> for some days, I'm trying to understand if we have an integration issue >>>> with erofs or rather some upstream bug. After playing with various >>>> parameters, it rather looks like the latter: >>>> >>>> $ ls -l erofs-dir/ >>>> total 132 >>>> -rwxr-xr-x 1 1000 users 132868 Jul  8 10:50 dash >>>> (from Debian bookworm) >>>> $ mkfs.erofs -z lz4hc erofs.img erofs-dir/ >>>> mkfs.erofs 1.8.6 (trixie version, but same happens with bookworm 1.5) >>>> Build completed. >>>> ------ >>>> Filesystem UUID: aae0b2f0-4ee4-4850-af49-3c1aad7fa30c >>>> Filesystem total blocks: 17 (of 4096-byte blocks) >>>> Filesystem total inodes: 2 >>>> Filesystem total metadata blocks: 1 >>>> Filesystem total deduplicated bytes (of source files): 0 >>>> >>>> Now I have 6.15-rc5 and a defconfig-close setting for the 32-bit ARM >>>> target BeagleBone Black. When booting into init=/bin/sh, then running >>>> >>>> # mount -t erofs /dev/mmcblk0p1 /mnt >>>> erofs (device mmcblk0p1): mounted with root inode @ nid 36. >>>> # /mnt/dash >>>> Segmentation fault >>>> >>>> I once also got this: >>>> >>>> Alignment trap: not handling instruction 2b00 at [<004debc0>] >>>> 8<--- cut here --- >>>> Unhandled fault: alignment exception (0x001) at 0x000004d9 >>>> [000004d9] *pgd=00000000 >>>> Bus error >>>> >>>> All is fine if I >>>>   - run the command once more >>>>   - dump the file first (cat /mnt/dash > /dev/null; /mnt/dash) >>> >>> Forgot to mention: That first dump when done via md5sum or so actually >>> gives the right checksum. So pure reading of the binary is also ok, just >>> trying to load it for execution fails on the first attempt. >> >> Thanks for your report.  I rarely take care arm32 platform >> because I don't have such setup. >> >> but could you share a reproducible rootfs image and >> I wonder if qemu could reproduce this? > > The image can be generated from isar-cip-core > (https://gitlab.com/cip-project/cip-core/isar-cip-core), bbb image with > swupdate extension and erofs as immutable rootfs. As I wrote, those will > be 6.12 or 6.1 based, but I also injected a mainline kernel into that > with the same result. But all that only helps if you have some > beaglebone black in reach right now. Could you check 5.4 lts, 5.15 lts, 5.10 lts if possible? I wonder if it's a regression or it does not work from the beginning. Anyway, I have no chance to look after arm32 due to lack of use cases and hardware resource. > > The same configuration, just for qemuarm as target, unfortunately does > not reproduce the issue. That is too bad for me honestly because I do think it's much easier for me to quickly shooting down with a reproducable environment on my side... > >> >> Otherwise it's hard for me to debug this issue... > > If you tell me how I could do that, I'm happy to instrument and analyze. > I just have no understanding of erofs yet, specifically how reading > files might be different from loading executables. I have no idea too. But it seems this issue is quite similar to https://lore.kernel.org/r/76f0ea6f-d4c2-434a-8ca5-4bd93921209f@linux.alibaba.com/T/#t I've given several ways to help finding the cause, but it seems that data checksum is all good, and that issue is still not resolved now either. Thanks, Gao Xiang > > Jan >