Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933685AbaKRPNj (ORCPT ); Tue, 18 Nov 2014 10:13:39 -0500 Received: from cantor2.suse.de ([195.135.220.15]:57198 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754920AbaKROJd (ORCPT ); Tue, 18 Nov 2014 09:09:33 -0500 From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Mikulas Patocka , Al Viro , Jiri Slaby Subject: [PATCH 3.12 059/206] fs: make cont_expand_zero interruptible Date: Tue, 18 Nov 2014 15:06:54 +0100 Message-Id: X-Mailer: git-send-email 2.1.3 In-Reply-To: <28f04bcc068a44c5641c727883947960fb8dcbd5.1416319692.git.jslaby@suse.cz> References: <28f04bcc068a44c5641c727883947960fb8dcbd5.1416319692.git.jslaby@suse.cz> In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Mikulas Patocka 3.12-stable review patch. If anyone has any objections, please let me know. =============== 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: Jiri Slaby --- fs/buffer.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/fs/buffer.c b/fs/buffer.c index fe2182ec812d..dc1107fec557 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -2325,6 +2325,11 @@ 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 */ -- 2.1.3 -- 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/