From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail1.bemta37.messagelabs.com (mail1.bemta37.messagelabs.com [85.158.142.1]) (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 99CA320EB for ; Fri, 24 Mar 2023 04:19:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fujitsu.com; s=170520fj; t=1679631597; i=@fujitsu.com; bh=QoSk5cd0BqHUsY/u1N/oQyosJhqZq47WDn7uQS+DbOM=; h=Message-ID:Date:MIME-Version:Subject:To:CC:References:From: In-Reply-To:Content-Type:Content-Transfer-Encoding; b=aLGRlTPcMXkcd8LJAQCVqX40oyA8ZybnTI5pfSu/63W7l4kV+jBpJCQVoV+ELVIbJ L4MHpHEOVj3o6zBBsDxp9IVkcpiwq82BxBOtqKgBBm0nX+T5+ZUkElzoZ2vK0gzzW7 sSGXoGrp3ySDq1ZAr+WnF3MlekP5L9OAOWo4jHSb2c2zchVgPNnByzZ3yks93FGmOZ 0DAVtmZiiYL6ewjTJ3Mwr8eqfVtvxmtzkogL/y7MYRz/FhA8RnDrYBYRzDS09oysKc FupQPm2KN2FhSggfF2GE/qgoWzhOsFO/KXRGC6cRUGCupDdkduQYk1qZQDmTx0x1LE 9VjFO57dorHog== X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFlrEKsWRWlGSWpSXmKPExsViZ8ORpPtaRTb F4MVtE4s569ewWUyfeoHRYvb0ZiaLPXtPslis/PGH1eL3jzlsDmwem1doeSze85LJ48SM3ywe LzbPZPQ4s+AIu8fnTXIBbFGsmXlJ+RUJrBlnVvUzFpxSqTh5/T9zA+NK+S5GLg4hgY2MEv8b2 hi7GDmBnCVMEk1/xSES2xgl3iz7xQyS4BWwk9j05SWYzSKgKtF6cxITRFxQ4uTMJywgtqhAss Sx861sILawgJ/E6lU9rCC2iICuxKrnu5hBhjILNDJKXJzZxgSx4TujxPWObrAONgEdiQsL/oJ 1cAp4S6zu+ga2gVnAQmLxm4PsELa8RPPW2WBXSAgoSVz8eocVwq6QaJx+iAnCVpO4em4T8wRG oVlIDpyFZNQsJKMWMDKvYjQrTi0qSy3SNdZLKspMzyjJTczM0Uus0k3USy3VzcsvKsnQNdRLL C/WSy0u1iuuzE3OSdHLSy3ZxAiMqJTiRKEdjN96/+odYpTkYFIS5ZUIlU4R4kvKT6nMSCzOiC 8qzUktPsQow8GhJMHrqiSbIiRYlJqeWpGWmQOMbpi0BAePkgivtBhQmre4IDG3ODMdInWK0Zh jbcOBvcwcGx4ASSGWvPy8VClx3gQpoFIBkNKM0jy4QbCkc4lRVkqYl5GBgUGIpyC1KDezBFX+ FaM4B6OSMG+2MtAUnsy8Erh9r4BOYQI6xblGBuSUkkSElFQD0xL3Uv+Y9sNb02yfHd3w4srKP L1kkZo/3kWrM2p8hOMSdC/M+rlm59ocY/v6wCWx95mZ0hKWRv34GfPYuE2w6q51ktSv+gzLg5 yvOBN33XuvmpB+ZPufM1qaAks9JL1L+5V6nS+mpaRPXjTNRvOH+KnAuV+dFrrrx7Lt/rytlUP xzcZpO77PcJE40fw5RidTf/FroYL9bM8fql9ebDShp4mzn0tuovvG6YsS11abbbi1riWj4paO 4pyU/FjFBann1ml4xjOE2rL/uNtSOP0Lp/TNfvFFX5Rqs7W+LWucet062TjrxmWpa+FvXE5M2 sZ5zunq+0zHhoCw1pogftYjdgl/Dk2ZtX/ivHaNzaeXKbEUZyQaajEXFScCANkKIqi1AwAA X-Env-Sender: ruansy.fnst@fujitsu.com X-Msg-Ref: server-3.tower-745.messagelabs.com!1679631595!658583!1 X-Originating-IP: [62.60.8.98] X-SYMC-ESS-Client-Auth: outbound-route-from=pass X-StarScan-Received: X-StarScan-Version: 9.104.1; banners=-,-,- X-VirusChecked: Checked Received: (qmail 23174 invoked from network); 24 Mar 2023 04:19:55 -0000 Received: from unknown (HELO n03ukasimr03.n03.fujitsu.local) (62.60.8.98) by server-3.tower-745.messagelabs.com with ECDHE-RSA-AES256-GCM-SHA384 encrypted SMTP; 24 Mar 2023 04:19:55 -0000 Received: from n03ukasimr03.n03.fujitsu.local (localhost [127.0.0.1]) by n03ukasimr03.n03.fujitsu.local (Postfix) with ESMTP id 2F5491B5; Fri, 24 Mar 2023 04:19:55 +0000 (GMT) Received: from R01UKEXCASM121.r01.fujitsu.local (R01UKEXCASM121 [10.183.43.173]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by n03ukasimr03.n03.fujitsu.local (Postfix) with ESMTPS id 23FE11AF; Fri, 24 Mar 2023 04:19:55 +0000 (GMT) Received: from [192.168.50.5] (10.167.234.230) by R01UKEXCASM121.r01.fujitsu.local (10.183.43.173) with Microsoft SMTP Server (TLS) id 15.0.1497.42; Fri, 24 Mar 2023 04:19:52 +0000 Message-ID: Date: Fri, 24 Mar 2023 12:19:46 +0800 Precedence: bulk X-Mailing-List: nvdimm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.7.1 Subject: Re: [PATCH] fsdax: dedupe should compare the min of two iters' length To: Andrew Morton CC: , , , , References: <1679469958-2-1-git-send-email-ruansy.fnst@fujitsu.com> <20230322161236.f90c21c8f668f551ee19d80b@linux-foundation.org> <0d219eb0-0f58-e667-0d86-be158ea2030f@fujitsu.com> <20230323151201.98d54f8d85f83c636568eacc@linux-foundation.org> From: Shiyang Ruan In-Reply-To: <20230323151201.98d54f8d85f83c636568eacc@linux-foundation.org> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-Originating-IP: [10.167.234.230] X-ClientProxiedBy: G08CNEXCHPEKD07.g08.fujitsu.local (10.167.33.80) To R01UKEXCASM121.r01.fujitsu.local (10.183.43.173) X-Virus-Scanned: ClamAV using ClamSMTP 在 2023/3/24 6:12, Andrew Morton 写道: > On Thu, 23 Mar 2023 14:48:25 +0800 Shiyang Ruan wrote: > >> >> >> 在 2023/3/23 7:12, Andrew Morton 写道: >>> On Wed, 22 Mar 2023 07:25:58 +0000 Shiyang Ruan wrote: >>> >>>> In an dedupe corporation iter loop, the length of iomap_iter decreases >>>> because it implies the remaining length after each iteration. The >>>> compare function should use the min length of the current iters, not the >>>> total length. >>> >>> Please describe the user-visible runtime effects of this flaw, thanks. >> >> This patch fixes fail of generic/561, with test config: >> >> export TEST_DEV=/dev/pmem0 >> export TEST_DIR=/mnt/test >> export SCRATCH_DEV=/dev/pmem1 >> export SCRATCH_MNT=/mnt/scratch >> export MKFS_OPTIONS="-m reflink=1,rmapbt=1" >> export MOUNT_OPTIONS="-o dax" >> export XFS_MOUNT_OPTIONS="-o dax" > > Again, how does the bug impact real-world kernel users? The dedupe command will fail with -EIO if the range is larger than one page size and not aligned to the page size. Also report warning in dmesg: [ 4338.498374] ------------[ cut here ]------------ [ 4338.498689] WARNING: CPU: 3 PID: 1415645 at fs/iomap/iter.c:16 iomap_iter+0x2b2/0x2c0 [ 4338.499216] Modules linked in: bfq ext4 mbcache jbd2 auth_rpcgss oid_registry nfsv4 algif_hash af_alg af_packet nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat iptable_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip_set nf_tables nfnetlink ip6table_filter ip6_tables iptable_filter ip_tables x_tables nd_pmem nd_btt dax_pmem sch_fq_codel configfs xfs libcrc32c fuse [last unloaded: scsi_debug] [ 4338.501419] CPU: 3 PID: 1415645 Comm: pool Kdump: loaded Tainted: G W 6.1.0-rc4+ #118 242c3ad9724cd53a53c9a3b3cd3050ef1060e37a [ 4338.502093] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS Arch Linux 1.16.0-3-3 04/01/2014 [ 4338.502610] RIP: 0010:iomap_iter+0x2b2/0x2c0 [ 4338.502933] Code: 0d 63 6f ce 7e 0f 85 d0 fe ff ff e8 f4 ea cc ff e9 c6 fe ff ff 0f 0b e9 a0 fe ff ff 0f 0b e9 a5 fe ff ff 0f 0b e9 85 fe ff ff <0f> 0b b8 fb ff ff ff e9 aa fe ff ff cc cc 0f 1f 44 00 00 48 8b 42 [ 4338.503963] RSP: 0018:ffffc9000317faa8 EFLAGS: 00010287 [ 4338.504318] RAX: 0000000000000178 RBX: ffffc9000317fba8 RCX: 0000000000001000 [ 4338.504701] RDX: 0000000000000178 RSI: 0000000000399000 RDI: ffffc9000317fba8 [ 4338.505062] RBP: ffffffffa0321b30 R08: ffffc9000317fae0 R09: 0000000000000000 [ 4338.505490] R10: 0000000000000004 R11: ffff888102577740 R12: ffffc9000317fd00 [ 4338.505956] R13: 0000000000399000 R14: 0000000000001000 R15: 0000000000000000 [ 4338.506460] FS: 00007f57ce200640(0000) GS:ffff88817bd80000(0000) knlGS:0000000000000000 [ 4338.507126] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 4338.507490] CR2: 00007f57b4a00e88 CR3: 0000000153669002 CR4: 00000000003706e0 [ 4338.507887] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 4338.508288] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 4338.508717] Call Trace: [ 4338.508962] [ 4338.509234] dax_dedupe_file_range_compare+0xd9/0x210 [ 4338.509589] __generic_remap_file_range_prep+0x2af/0x760 [ 4338.509942] xfs_reflink_remap_prep+0xeb/0x240 [xfs 4155ff90e551a4608ed7504e9f2aa737a690cfa3] [ 4338.510505] xfs_file_remap_range+0x83/0x320 [xfs 4155ff90e551a4608ed7504e9f2aa737a690cfa3] [ 4338.511118] vfs_dedupe_file_range_one+0x196/0x1b0 [ 4338.511407] vfs_dedupe_file_range+0x170/0x1e0 [ 4338.511719] do_vfs_ioctl+0x48d/0x8f0 [ 4338.511975] ? kmem_cache_free+0x2a1/0x460 [ 4338.512278] ? do_sys_openat2+0x7d/0x150 [ 4338.512556] __x64_sys_ioctl+0x40/0xa0 [ 4338.512829] do_syscall_64+0x2b/0x80 [ 4338.513109] entry_SYSCALL_64_after_hwframe+0x46/0xb0 [ 4338.513421] RIP: 0033:0x7f57ce50748f [ 4338.513687] Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 18 48 8b 44 24 18 64 48 2b 04 25 28 00 00 [ 4338.514582] RSP: 002b:00007f57ce1ffbb0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 4338.515067] RAX: ffffffffffffffda RBX: 00007f57b4885870 RCX: 00007f57ce50748f [ 4338.515441] RDX: 00007f57b4885870 RSI: 00000000c0189436 RDI: 000000000000000e [ 4338.516300] RBP: 00007f57b486f648 R08: 0000000000000001 R09: 00007f57b486f650 [ 4338.516694] R10: 0000000000000000 R11: 0000000000000246 R12: 00007f57b486f650 [ 4338.517108] R13: 00007f57b486f610 R14: 00007f57b486f650 R15: 00007f57b486f610 [ 4338.518781] [ 4338.519037] ---[ end trace 0000000000000000 ]--- -- Thanks, Ruan. > > Thanks.