From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 65B0215492 for ; Mon, 23 Oct 2023 11:24:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="vxRGoBy7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D43F8C433C7; Mon, 23 Oct 2023 11:24:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1698060282; bh=Z1SQ45qHpzJ2QYltwWA7vXA3S9Lz4dSRof8jE0QOXJ8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=vxRGoBy7zGo+G5F/Cv/aAq+fparbRMn0hLLxsg16g9+1ENWIN44ZI8oMWEdgpzRYQ n0jkBMtX/moIXIopJ6l50F9uxmGqs486IHwKcqW3nzVeF9h0PqqxLGIwD6oPE/OCSP HKzJlgfN6wzH/EMoajBVFJCX4P2soFNvy0IJXOP0= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Filipe Manana , David Sterba , Sasha Levin Subject: [PATCH 6.1 120/196] btrfs: error when COWing block from a root that is being deleted Date: Mon, 23 Oct 2023 12:56:25 +0200 Message-ID: <20231023104831.902305905@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20231023104828.488041585@linuxfoundation.org> References: <20231023104828.488041585@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Filipe Manana [ Upstream commit a2caab29884397e583d09be6546259a83ebfbdb1 ] At btrfs_cow_block() we check if the block being COWed belongs to a root that is being deleted and if so we log an error message. However this is an unexpected case and it indicates a bug somewhere, so we should return an error and abort the transaction. So change this in the following ways: 1) Abort the transaction with -EUCLEAN, so that if the issue ever happens it can easily be noticed; 2) Change the logged message level from error to critical, and change the message itself to print the block's logical address and the ID of the root; 3) Return -EUCLEAN to the caller; 4) As this is an unexpected scenario, that should never happen, mark the check as unlikely, allowing the compiler to potentially generate better code. Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Sasha Levin --- fs/btrfs/ctree.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index 98e3e0761a4e5..98f68bd1383a3 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -563,9 +563,13 @@ noinline int btrfs_cow_block(struct btrfs_trans_handle *trans, u64 search_start; int ret; - if (test_bit(BTRFS_ROOT_DELETING, &root->state)) - btrfs_err(fs_info, - "COW'ing blocks on a fs root that's being dropped"); + if (unlikely(test_bit(BTRFS_ROOT_DELETING, &root->state))) { + btrfs_abort_transaction(trans, -EUCLEAN); + btrfs_crit(fs_info, + "attempt to COW block %llu on root %llu that is being deleted", + buf->start, btrfs_root_id(root)); + return -EUCLEAN; + } /* * COWing must happen through a running transaction, which always -- 2.40.1