From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261873AbTJIBwn (ORCPT ); Wed, 8 Oct 2003 21:52:43 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261875AbTJIBwn (ORCPT ); Wed, 8 Oct 2003 21:52:43 -0400 Received: from mail.jlokier.co.uk ([81.29.64.88]:53386 "EHLO mail.shareable.org") by vger.kernel.org with ESMTP id S261873AbTJIBwl (ORCPT ); Wed, 8 Oct 2003 21:52:41 -0400 Date: Thu, 9 Oct 2003 02:52:32 +0100 From: Jamie Lokier To: Linus Torvalds Cc: linux-kernel@vger.kernel.org Subject: [PATCH] set sigio target to current->pid and only if not already set Message-ID: <20031009015232.GA18112@mail.shareable.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Patch: f_setown-2.6.0-test6.patch Dear Linus, Two minor changes: 1. send_sigio() sends to a specific thread, _not_ a process. (It can also send to a process group, but that's not relevant here). This is useful, and should stay as it is. Therefore it makes _no sense_ to call f_setown() with current->tgid. Presently the kernel is inconsistent about it, with some places using current->pid and some others using current->tgid. This patch changes f_setown() calls to use current->pid. 2. In some places, f_setown() is called not at the user's direct request, but as a side effect of another function. Specifically: dnotify and file leases. It is good to allow a program the flexibility to specify a different pid than the default, using F_SETOWN. Presently they can do this after the dnotify or lease call, but there is a small time window when it will be temporarily set to current->tgid (which as pointed out above, is not always right). The window is avoidable if the program can use F_SETOWN prior to the dnotify or lease call. This is exactly what the "force" argument to f_setown() is for, and this patch changes it to zero in those callers. This change is not likely to affect any existing programs. Please apply. -- Jamie diff -urN --exclude-from=dontdiff orig-2.6.0-test6/fs/dnotify.c f_setown-2.6.0-test6/fs/dnotify.c --- orig-2.6.0-test6/fs/dnotify.c 2003-09-13 21:21:25.000000000 +0100 +++ f_setown-2.6.0-test6/fs/dnotify.c 2003-10-09 01:49:13.000000000 +0100 @@ -92,7 +92,7 @@ prev = &odn->dn_next; } - error = f_setown(filp, current->tgid, 1); + error = f_setown(filp, current->pid, 0); if (error) goto out_free; diff -urN --exclude-from=dontdiff orig-2.6.0-test6/fs/locks.c f_setown-2.6.0-test6/fs/locks.c --- orig-2.6.0-test6/fs/locks.c 2003-09-30 05:40:50.000000000 +0100 +++ f_setown-2.6.0-test6/fs/locks.c 2003-10-09 01:49:37.000000000 +0100 @@ -1268,7 +1268,7 @@ locks_insert_lock(before, fl); - error = f_setown(filp, current->tgid, 1); + error = f_setown(filp, current->pid, 0); out_unlock: unlock_kernel(); return error; diff -urN --exclude-from=dontdiff orig-2.6.0-test6/kernel/futex.c f_setown-2.6.0-test6/kernel/futex.c --- orig-2.6.0-test6/kernel/futex.c 2003-09-30 05:41:14.000000000 +0100 +++ f_setown-2.6.0-test6/kernel/futex.c 2003-10-09 01:52:37.000000000 +0100 @@ -500,7 +500,7 @@ if (signal) { int err; - err = f_setown(filp, current->tgid, 1); + err = f_setown(filp, current->pid, 1); if (err < 0) { put_unused_fd(ret); put_filp(filp);