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 55292C678D5 for ; Wed, 8 Mar 2023 01:31:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230104AbjCHBb1 (ORCPT ); Tue, 7 Mar 2023 20:31:27 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48922 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230043AbjCHBbX (ORCPT ); Tue, 7 Mar 2023 20:31:23 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 640ED32CDC for ; Tue, 7 Mar 2023 17:31:21 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 25F16B81B4F for ; Wed, 8 Mar 2023 01:31:20 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D9BD5C433EF; Wed, 8 Mar 2023 01:31:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1678239078; bh=I10H3LCRynxbID+LAh2eXQNF43+fQKoY+xvwLhKFR5c=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=jCpFjJZtSzM3h3ToioEEQGRsNEC4NWiKXflrV6Y49nzZzn8WGmoxZ//hXVssshpz2 9iCXUnVA8TPWU77K5VIGmZGbnllwlc0m2BeppetfkmyHWzV5s9zv5Dv/YEG7Mpq+Lw JbT7xO+J2Z0z2toKR+/NHy9UYV9D1xRIs+DFLDAleXAaBn48cmRIYlsomH4yAPC00Z voc5n3dNe3Ac2ndx2TW++F+PYyTBrx0rw+CUOOTlz6uNGvUNFm0YFkSmn9cYRQS6l3 gXtkjdgHPS+9TBCu//G5e8TsVDbslJKFuuVTginj+y9SEnUnEiGLOtICNWiHTqA4v8 HmviJLVjWhCgw== Message-ID: Date: Wed, 8 Mar 2023 09:31:15 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.7.2 Subject: Re: [PATCH] f2fs: fix unaligned field offset in 32-bits platform Content-Language: en-US To: Jaegeuk Kim Cc: linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, Zhiguo Niu References: <20230307151408.58490-1-chao@kernel.org> From: Chao Yu In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2023/3/8 1:26, Jaegeuk Kim wrote: > Cc'ed stable. Thanks. Oh, thanks for adding the missed tag! Jaegeuk. Thanks, > > On 03/07, Chao Yu wrote: >> F2FS-fs (dm-x): inconsistent rbtree, cur(3470333575168) next(3320009719808) >> ------------[ cut here ]------------ >> kernel BUG at fs/f2fs/gc.c:602! >> Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM >> PC is at get_victim_by_default+0x13c0/0x1498 >> LR is at f2fs_check_rb_tree_consistence+0xc4/0xd4 >> .... >> [] (get_victim_by_default) from [] (f2fs_gc+0x220/0x6cc) >> [] (f2fs_gc) from [] (gc_thread_func+0x2ac/0x708) >> [] (gc_thread_func) from [] (kthread+0x1a8/0x1b4) >> [] (kthread) from [] (ret_from_fork+0x14/0x20) >> >> The reason is there is __packed attribute in struct rb_entry, but there >> is no __packed attribute in struct victim_entry, so wrong offset of key >> field will be parsed in struct rb_entry in f2fs_check_rb_tree_consistence, >> it describes memory layouts of struct rb_entry and struct victim_entry in >> 32-bits platform as below: >> >> struct rb_entry { >> [0] struct rb_node rb_node; >> union { >> struct {...}; >> [12] unsigned long long key; >> } __packed; >> } >> size of struct rb_entry: 20 >> >> struct victim_entry { >> [0] struct rb_node rb_node; >> union { >> struct {...}; >> [16] struct victim_info vi; >> }; >> [32] struct list_head list; >> } >> size of struct victim_entry: 40 >> >> This patch tries to add __packed attribute in below structure: >> - discard_info, discard_cmd >> - extent_info, extent_node >> - victim_info, victim_entry >> in order to fix this unaligned field offset issue in 32-bits platform. >> >> Fixes: 004b68621897 ("f2fs: use rb-tree to track pending discard commands") >> Fixes: 13054c548a1c ("f2fs: introduce infra macro and data structure of rb-tree extent cache") >> Fixes: 093749e296e2 ("f2fs: support age threshold based garbage collection") >> Signed-off-by: Zhiguo Niu >> Signed-off-by: Chao Yu >> --- >> fs/f2fs/f2fs.h | 6 +++--- >> fs/f2fs/gc.h | 4 ++-- >> 2 files changed, 5 insertions(+), 5 deletions(-) >> >> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h >> index b0ab2062038a..17fa7572ceed 100644 >> --- a/fs/f2fs/f2fs.h >> +++ b/fs/f2fs/f2fs.h >> @@ -349,7 +349,7 @@ struct discard_info { >> block_t lstart; /* logical start address */ >> block_t len; /* length */ >> block_t start; /* actual start address in dev */ >> -}; >> +} __packed; >> >> struct discard_cmd { >> struct rb_node rb_node; /* rb node located in rb-tree */ >> @@ -361,7 +361,7 @@ struct discard_cmd { >> }; >> struct discard_info di; /* discard info */ >> >> - }; >> + } __packed; >> struct list_head list; /* command list */ >> struct completion wait; /* compleation */ >> struct block_device *bdev; /* bdev */ >> @@ -660,7 +660,7 @@ struct extent_info { >> unsigned long long last_blocks; >> }; >> }; >> -}; >> +} __packed; >> >> struct extent_node { >> struct rb_node rb_node; /* rb node located in rb-tree */ >> diff --git a/fs/f2fs/gc.h b/fs/f2fs/gc.h >> index 15bd1d680f67..304937d9a084 100644 >> --- a/fs/f2fs/gc.h >> +++ b/fs/f2fs/gc.h >> @@ -58,7 +58,7 @@ struct gc_inode_list { >> struct victim_info { >> unsigned long long mtime; /* mtime of section */ >> unsigned int segno; /* section No. */ >> -}; >> +} __packed; >> >> struct victim_entry { >> struct rb_node rb_node; /* rb node located in rb-tree */ >> @@ -68,7 +68,7 @@ struct victim_entry { >> unsigned int segno; /* segment No. */ >> }; >> struct victim_info vi; /* victim info */ >> - }; >> + } __packed; >> struct list_head list; >> }; >> >> -- >> 2.36.1