Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755826AbaKYLkZ (ORCPT ); Tue, 25 Nov 2014 06:40:25 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:58407 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753180AbaKYKl1 (ORCPT ); Tue, 25 Nov 2014 05:41:27 -0500 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Mikulas Patocka , Al Viro , Luis Henriques Subject: [PATCH 3.16.y-ckt 084/254] fs: make cont_expand_zero interruptible Date: Tue, 25 Nov 2014 10:37:14 +0000 Message-Id: <1416912004-5928-85-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1416912004-5928-1-git-send-email-luis.henriques@canonical.com> References: <1416912004-5928-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.7-ckt2 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Mikulas Patocka commit c2ca0fcd202863b14bd041a7fece2e789926c225 upstream. This patch makes it possible to kill a process looping in cont_expand_zero. A process may spend a lot of time in this function, so it is desirable to be able to kill it. It happened to me that I wanted to copy a piece data from the disk to a file. By mistake, I used the "seek" parameter to dd instead of "skip". Due to the "seek" parameter, dd attempted to extend the file and became stuck doing so - the only possibility was to reset the machine or wait many hours until the filesystem runs out of space and cont_expand_zero fails. We need this patch to be able to terminate the process. Signed-off-by: Mikulas Patocka Signed-off-by: Al Viro Signed-off-by: Luis Henriques --- fs/buffer.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/fs/buffer.c b/fs/buffer.c index 19a78d074e0d..4752094053f9 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -2328,6 +2328,11 @@ static int cont_expand_zero(struct file *file, struct address_space *mapping, err = 0; balance_dirty_pages_ratelimited(mapping); + + if (unlikely(fatal_signal_pending(current))) { + err = -EINTR; + goto out; + } } /* page covers the boundary, find the boundary offset */ -- 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/