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 4D3B0CE7A8D for ; Sun, 24 Sep 2023 13:16:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230155AbjIXNRD (ORCPT ); Sun, 24 Sep 2023 09:17:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46036 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229968AbjIXNQh (ORCPT ); Sun, 24 Sep 2023 09:16:37 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0447710E4; Sun, 24 Sep 2023 06:16:08 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5C12AC433C9; Sun, 24 Sep 2023 13:16:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1695561367; bh=+xsTH2ykECo9CCImthEN6cot/fkcwZ33b/9vCNDxeO8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TUOaqYTRgWtY8sauJgqcU6MZkpGymcSz0/9bUmubMl95DSaTLI0C3NPLw48y0nYLA YYQhS6CRt65cKkgcap0mMzal+JxF5K7i/3ecc+bHUHggX6GjM8XS63Xj/oVCOD1pHU 4qAaHIWWblZSffshtGtiUa544mjZOfy29XmSL+9P7AnrPo8LAaZKCxLDAtL5iOl3yf V91ktpWTOUNZ94sXS2K2wL0JpqAK/HU5qpgpkcdDfXQWzK3wlY8OGGnKZaBnOz4EHv XZ0buNE1ybbIIbQJOUFVBjoRRZVMoOzJhKrK8OxWZCrWKhHi5O4XJRHPWkLOoPonYo zde0sDl1CobVw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Filipe Manana , Qu Wenruo , David Sterba , Sasha Levin , clm@fb.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org Subject: [PATCH AUTOSEL 6.5 15/41] btrfs: assert delayed node locked when removing delayed item Date: Sun, 24 Sep 2023 09:15:03 -0400 Message-Id: <20230924131529.1275335-15-sashal@kernel.org> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230924131529.1275335-1-sashal@kernel.org> References: <20230924131529.1275335-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.5.5 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Filipe Manana [ Upstream commit a57c2d4e46f519b24558ae0752c17eec416ac72a ] When removing a delayed item, or releasing which will remove it as well, we will modify one of the delayed node's rbtrees and item counter if the delayed item is in one of the rbtrees. This require having the delayed node's mutex locked, otherwise we will race with other tasks modifying the rbtrees and the counter. This is motivated by a previous version of another patch actually calling btrfs_release_delayed_item() after unlocking the delayed node's mutex and against a delayed item that is in a rbtree. So assert at __btrfs_remove_delayed_item() that the delayed node's mutex is locked. Reviewed-by: Qu Wenruo Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Sasha Levin --- fs/btrfs/delayed-inode.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/fs/btrfs/delayed-inode.c b/fs/btrfs/delayed-inode.c index 88db451697b0a..f7fb42833e9db 100644 --- a/fs/btrfs/delayed-inode.c +++ b/fs/btrfs/delayed-inode.c @@ -412,6 +412,7 @@ static void finish_one_item(struct btrfs_delayed_root *delayed_root) static void __btrfs_remove_delayed_item(struct btrfs_delayed_item *delayed_item) { + struct btrfs_delayed_node *delayed_node = delayed_item->delayed_node; struct rb_root_cached *root; struct btrfs_delayed_root *delayed_root; @@ -419,18 +420,21 @@ static void __btrfs_remove_delayed_item(struct btrfs_delayed_item *delayed_item) if (RB_EMPTY_NODE(&delayed_item->rb_node)) return; - delayed_root = delayed_item->delayed_node->root->fs_info->delayed_root; + /* If it's in a rbtree, then we need to have delayed node locked. */ + lockdep_assert_held(&delayed_node->mutex); + + delayed_root = delayed_node->root->fs_info->delayed_root; BUG_ON(!delayed_root); if (delayed_item->type == BTRFS_DELAYED_INSERTION_ITEM) - root = &delayed_item->delayed_node->ins_root; + root = &delayed_node->ins_root; else - root = &delayed_item->delayed_node->del_root; + root = &delayed_node->del_root; rb_erase_cached(&delayed_item->rb_node, root); RB_CLEAR_NODE(&delayed_item->rb_node); - delayed_item->delayed_node->count--; + delayed_node->count--; finish_one_item(delayed_root); } -- 2.40.1