From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932093AbYEMUPj (ORCPT ); Tue, 13 May 2008 16:15:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1761905AbYEMUNx (ORCPT ); Tue, 13 May 2008 16:13:53 -0400 Received: from cantor2.suse.de ([195.135.220.15]:37959 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761895AbYEMUNw (ORCPT ); Tue, 13 May 2008 16:13:52 -0400 Date: Tue, 13 May 2008 13:11:49 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: Justin Forbes , Zwane Mwaikambo , "Theodore Ts'o" , Randy Dunlap , Dave Jones , Chuck Wolber , Chris Wedgwood , Michael Krufky , Chuck Ebbert , Domenico Andreoli , torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, "David S. Miller" Subject: [patch 08/37] sparc: Fix fork/clone/vfork system call restart. Message-ID: <20080513201149.GI31167@suse.de> References: <20080513200453.064446337@mini.kroah.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline; filename="sparc-fix-fork-clone-vfork-system-call-restart.patch" In-Reply-To: <20080513201053.GA31167@suse.de> User-Agent: Mutt/1.5.16 (2007-06-09) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.25-stable review patch. If anyone has any objections, please let us know. ------------------ From: David S. Miller [ Upstream commit: 1e38c126c9252b612697e34f43b1b3371c8ee31d ] We clobber %i1 as well as %i0 for these system calls, because they give two return values. Therefore, on error, we have to restore %i1 properly or else the restart explodes since it uses the wrong arguments. This fixes glibc's nptl/tst-eintr1.c testcase. Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- arch/sparc/kernel/process.c | 20 ++++++++++++++++---- arch/sparc64/kernel/process.c | 18 +++++++++++++++--- 2 files changed, 31 insertions(+), 7 deletions(-) --- a/arch/sparc64/kernel/process.c +++ b/arch/sparc64/kernel/process.c @@ -507,6 +507,8 @@ asmlinkage long sparc_do_fork(unsigned l unsigned long stack_size) { int __user *parent_tid_ptr, *child_tid_ptr; + unsigned long orig_i1 = regs->u_regs[UREG_I1]; + long ret; #ifdef CONFIG_COMPAT if (test_thread_flag(TIF_32BIT)) { @@ -519,9 +521,19 @@ asmlinkage long sparc_do_fork(unsigned l child_tid_ptr = (int __user *) regs->u_regs[UREG_I4]; } - return do_fork(clone_flags, stack_start, - regs, stack_size, - parent_tid_ptr, child_tid_ptr); + ret = do_fork(clone_flags, stack_start, + regs, stack_size, + parent_tid_ptr, child_tid_ptr); + + /* If we get an error and potentially restart the system + * call, we're screwed because copy_thread() clobbered + * the parent's %o1. So detect that case and restore it + * here. + */ + if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK) + regs->u_regs[UREG_I1] = orig_i1; + + return ret; } /* Copy a Sparc thread. The fork() return value conventions --- a/arch/sparc/kernel/process.c +++ b/arch/sparc/kernel/process.c @@ -421,14 +421,26 @@ asmlinkage int sparc_do_fork(unsigned lo unsigned long stack_size) { unsigned long parent_tid_ptr, child_tid_ptr; + unsigned long orig_i1 = regs->u_regs[UREG_I1]; + long ret; parent_tid_ptr = regs->u_regs[UREG_I2]; child_tid_ptr = regs->u_regs[UREG_I4]; - return do_fork(clone_flags, stack_start, - regs, stack_size, - (int __user *) parent_tid_ptr, - (int __user *) child_tid_ptr); + ret = do_fork(clone_flags, stack_start, + regs, stack_size, + (int __user *) parent_tid_ptr, + (int __user *) child_tid_ptr); + + /* If we get an error and potentially restart the system + * call, we're screwed because copy_thread() clobbered + * the parent's %o1. So detect that case and restore it + * here. + */ + if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK) + regs->u_regs[UREG_I1] = orig_i1; + + return ret; } /* Copy a Sparc thread. The fork() return value conventions --