From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E3912C43334 for ; Wed, 8 Jun 2022 05:28:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232777AbiFHF2c (ORCPT ); Wed, 8 Jun 2022 01:28:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52338 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233792AbiFHF2P (ORCPT ); Wed, 8 Jun 2022 01:28:15 -0400 Received: from mail-pj1-x102d.google.com (mail-pj1-x102d.google.com [IPv6:2607:f8b0:4864:20::102d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DFE2D1775C1 for ; Tue, 7 Jun 2022 19:42:42 -0700 (PDT) Received: by mail-pj1-x102d.google.com with SMTP id gd1so17362193pjb.2 for ; Tue, 07 Jun 2022 19:42:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=eACAcP76K1gXeQHMPXfrh6MRwMHogkqclcM3ucohxaU=; b=DtL5BKl38TK1JmQCoo9VNTuilRXtIQQb8aA+2j5JWDKkTJMcHWV5I4ayrf85wEAp/D +SPamuT0V/GS1H3+TGA7bsJrj/vQJTAzHMhmUFqbAjw6QppecD8ydZLJWGxGusTbuS3B DrmzebuZhbfui1ZylFkqA44lBIOUX+RiD7kEk= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=eACAcP76K1gXeQHMPXfrh6MRwMHogkqclcM3ucohxaU=; b=fUw32q+Q7c6tFXyhNDTf05XFpnDdb9ODdxXkppjy2mSurHv2AUnn87rG8juRqZwT6c KnZnUiLnEuAspJ926S3ocVBhXgUra/I5wbpXPSPOBvAbFlxlzY7AmI3yZb1szwc/Xfeg RRc1ydgao+sNctSoA4T+pc1x8Rfn6QOXvqjNbXfbzCXz+MLGP0uGZ6oxc5VEAp1iEY6o rXuAkjFyqRoD5YMvOQKKRoKL/w+WEfdpHG68iJ/L4SdA9Y7uSJLY7Jd+2jqNDk69RbVE /R6MSHLXE0yg8hFAR7BAWOCm+i5qh+J7ZfqsbHrx5VSn/YlI3+hzh9yTGZgTLkd66NYg vrWw== X-Gm-Message-State: AOAM5337THlFqPKSK7GYmQKHxED1Aio8bKpvaw1p8eRIo6oBp5XarCxH ywB0Xgi617/7qx9HzZFIJl+PoQ== X-Google-Smtp-Source: ABdhPJzYCcpDtcoi5LZAO+0GSYALVef0pXg5v/EV8ii/oeXqYV5OV4RF4wJ5iDiynw1qdkxhjkSp7A== X-Received: by 2002:a17:902:6bc6:b0:166:3c39:50a1 with SMTP id m6-20020a1709026bc600b001663c3950a1mr31493176plt.36.1654656158650; Tue, 07 Jun 2022 19:42:38 -0700 (PDT) Received: from google.com ([2401:fa00:8f:203:463d:a192:6128:66e]) by smtp.gmail.com with ESMTPSA id n7-20020aa78a47000000b0051bb61c0eacsm13512317pfa.20.2022.06.07.19.42.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 07 Jun 2022 19:42:38 -0700 (PDT) Date: Wed, 8 Jun 2022 11:42:33 +0900 From: Sergey Senozhatsky To: Minchan Kim Cc: Naresh Kamboju , open list , linux-fsdevel@vger.kernel.org, Linux ARM , "open list:KERNEL SELFTEST FRAMEWORK" , linux-block , regressions@lists.linux.dev, Jens Axboe , Nitin Gupta , Sergey Senozhatsky Subject: Re: qemu-arm: zram: mkfs.ext4 : Unable to handle kernel NULL pointer dereference at virtual address 00000140 Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On (22/06/08 11:39), Sergey Senozhatsky wrote: > On (22/06/07 16:52), Minchan Kim wrote: > > > rootfs: https://oebuilds.tuxbuild.com/29zhlbEc3EWq2wod9Uy964Bp27q/images/am57xx-evm/rpb-console-image-lkft-am57xx-evm-20220601222434.rootfs.ext4.gz > > > kernel: https://builds.tuxbuild.com/29zhqJJizU2Y7Ka7ArhryUOrNDC/zImage > > > > > > Boot command, > > > /usr/bin/qemu-system-aarch64 -cpu host,aarch64=off -machine > > > virt-2.10,accel=kvm -nographic -net > > > nic,model=virtio,maaacaddr=BA:DD:AD:CC:09:04 -net tap -m 2048 -monitor > > > none -kernel kernel/zImage --append "console=ttyAMA0 root=/dev/vda rw" > > > -hda rootfs/rpb-console-image-lkft-am57xx-evm-20220601222434.rootfs.ext4 > > > -m 4096 -smp 2 > > > > > > # cd /opt/kselftests/default-in-kernel/zram > > > # ./zram.sh > > > > > > Allow me sometime I will try to bisect this problem. > > > > Thanks for sharing the info. > > > > I managed to work your rootfs with my local arm build > > based on the problematic git tip. > > However, I couldn't suceed to reproduce it. > > > > I needed to build zsmalloc/zram built-in instead of modules > > Is it related? Hmm, > > > > Yeah, It would be very helpful if you could help to bisect it. > > This looks like a NULL lock->name dereference in lockdep. I suspect > that somehow local_lock doesn't get .dep_map initialized. Maybe running > the kernel with CONFIG_DEBUG_LOCK_ALLOC would help us? Naresh, can you > help us with this? Hmm, actually, hold on. mapping_area is per-CPU, so what happens if CPU get offlined and onlined again? I don't see us re-initializing mapping_area local_lock_init(&zs_map_area.lock) and so on.