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 1FF9BCD13D1 for ; Sun, 17 Sep 2023 19:55:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240168AbjIQTzN (ORCPT ); Sun, 17 Sep 2023 15:55:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40832 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240188AbjIQTyu (ORCPT ); Sun, 17 Sep 2023 15:54:50 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3E3279F for ; Sun, 17 Sep 2023 12:54:45 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6A27AC433C7; Sun, 17 Sep 2023 19:54:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1694980484; bh=4subH2Gkn5jc7akX48FKXvWC2lyQJxi13NOtw5M2KXs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=covYjwqj7Ris9i+ahS6pAWa6alVRP4PuhrbAHkAKQ00kKs7YSC9uB0o/k++uqqfbX vyCul9Z0obdSANyrRu57WsZz/iefjs1DxcZup1zq5XRiOy2qmDAo0p4FnPboNbJV0z xRafJJOajLbZqRO8F7duKY5l4l9aodLt9DLP2d2M= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Filipe Manana , Josef Bacik , David Sterba Subject: [PATCH 6.5 206/285] btrfs: set page extent mapped after read_folio in relocate_one_page Date: Sun, 17 Sep 2023 21:13:26 +0200 Message-ID: <20230917191058.702058453@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20230917191051.639202302@linuxfoundation.org> References: <20230917191051.639202302@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 6.5-stable review patch. If anyone has any objections, please let me know. ------------------ From: Josef Bacik commit e7f1326cc24e22b38afc3acd328480a1183f9e79 upstream. One of the CI runs triggered the following panic assertion failed: PagePrivate(page) && page->private, in fs/btrfs/subpage.c:229 ------------[ cut here ]------------ kernel BUG at fs/btrfs/subpage.c:229! Internal error: Oops - BUG: 00000000f2000800 [#1] SMP CPU: 0 PID: 923660 Comm: btrfs Not tainted 6.5.0-rc3+ #1 pstate: 61400005 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--) pc : btrfs_subpage_assert+0xbc/0xf0 lr : btrfs_subpage_assert+0xbc/0xf0 sp : ffff800093213720 x29: ffff800093213720 x28: ffff8000932138b4 x27: 000000000c280000 x26: 00000001b5d00000 x25: 000000000c281000 x24: 000000000c281fff x23: 0000000000001000 x22: 0000000000000000 x21: ffffff42b95bf880 x20: ffff42b9528e0000 x19: 0000000000001000 x18: ffffffffffffffff x17: 667274622f736620 x16: 6e69202c65746176 x15: 0000000000000028 x14: 0000000000000003 x13: 00000000002672d7 x12: 0000000000000000 x11: ffffcd3f0ccd9204 x10: ffffcd3f0554ae50 x9 : ffffcd3f0379528c x8 : ffff800093213428 x7 : 0000000000000000 x6 : ffffcd3f091771e8 x5 : ffff42b97f333948 x4 : 0000000000000000 x3 : 0000000000000000 x2 : 0000000000000000 x1 : ffff42b9556cde80 x0 : 000000000000004f Call trace: btrfs_subpage_assert+0xbc/0xf0 btrfs_subpage_set_dirty+0x38/0xa0 btrfs_page_set_dirty+0x58/0x88 relocate_one_page+0x204/0x5f0 relocate_file_extent_cluster+0x11c/0x180 relocate_data_extent+0xd0/0xf8 relocate_block_group+0x3d0/0x4e8 btrfs_relocate_block_group+0x2d8/0x490 btrfs_relocate_chunk+0x54/0x1a8 btrfs_balance+0x7f4/0x1150 btrfs_ioctl+0x10f0/0x20b8 __arm64_sys_ioctl+0x120/0x11d8 invoke_syscall.constprop.0+0x80/0xd8 do_el0_svc+0x6c/0x158 el0_svc+0x50/0x1b0 el0t_64_sync_handler+0x120/0x130 el0t_64_sync+0x194/0x198 Code: 91098021 b0007fa0 91346000 97e9c6d2 (d4210000) This is the same problem outlined in 17b17fcd6d44 ("btrfs: set_page_extent_mapped after read_folio in btrfs_cont_expand") , and the fix is the same. I originally looked for the same pattern elsewhere in our code, but mistakenly skipped over this code because I saw the page cache readahead before we set_page_extent_mapped, not realizing that this was only in the !page case, that we can still end up with a !uptodate page and then do the btrfs_read_folio further down. The fix here is the same as the above mentioned patch, move the set_page_extent_mapped call to after the btrfs_read_folio() block to make sure that we have the subpage blocksize stuff setup properly before using the page. CC: stable@vger.kernel.org # 6.1+ Reviewed-by: Filipe Manana Signed-off-by: Josef Bacik Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman --- fs/btrfs/relocation.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) --- a/fs/btrfs/relocation.c +++ b/fs/btrfs/relocation.c @@ -3006,9 +3006,6 @@ static int relocate_one_page(struct inod if (!page) return -ENOMEM; } - ret = set_page_extent_mapped(page); - if (ret < 0) - goto release_page; if (PageReadahead(page)) page_cache_async_readahead(inode->i_mapping, ra, NULL, @@ -3024,6 +3021,15 @@ static int relocate_one_page(struct inod } } + /* + * We could have lost page private when we dropped the lock to read the + * page above, make sure we set_page_extent_mapped here so we have any + * of the subpage blocksize stuff we need in place. + */ + ret = set_page_extent_mapped(page); + if (ret < 0) + goto release_page; + page_start = page_offset(page); page_end = page_start + PAGE_SIZE - 1;