From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262941AbUKXX2U (ORCPT ); Wed, 24 Nov 2004 18:28:20 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262932AbUKXX0S (ORCPT ); Wed, 24 Nov 2004 18:26:18 -0500 Received: from pool-151-203-245-3.bos.east.verizon.net ([151.203.245.3]:26116 "EHLO ccure.user-mode-linux.org") by vger.kernel.org with ESMTP id S262944AbUKXXUf (ORCPT ); Wed, 24 Nov 2004 18:20:35 -0500 Message-Id: <200411242307.iAON7Mbn005428@ccure.user-mode-linux.org> X-Mailer: exmh version 2.4 06/23/2000 with nmh-1.1-RC1 To: akpm@osdl.org cc: linux-kernel@vger.kernel.org, Blaisorblade Subject: [PATCH] UML - Unregister signal handlers at reboot Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Wed, 24 Nov 2004 18:07:22 -0500 From: Jeff Dike Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org From: Bodo Stroesser In most cases reboot failed on my system. After "Restarting system.", UML exited without further messages. I found an SIGIO being processed by sig_handler() resp. sig_handler_common_skas(). Don't know, why this exits, maybe the context is no longer valid at this time. So, I changed the sequence in the reboot part of main() to stop the timers and disable the fds before unblocking the signals. Since this wasn't enough, I also added set_handler(SIGXXX, SIG_IGN) calls to disable_timer() and deactivate_all_fds(). Now reboot works fine in SKAS and it still works in TT. Signed-off-by: Bodo Stroesser Signed-off-by: Jeff Dike Index: 2.6.9/arch/um/kernel/irq_user.c =================================================================== --- 2.6.9.orig/arch/um/kernel/irq_user.c 2004-11-24 12:29:17.000000000 -0500 +++ 2.6.9/arch/um/kernel/irq_user.c 2004-11-24 12:29:36.000000000 -0500 @@ -377,6 +377,8 @@ if(err) return(err); } + /* If there is a signal already queued, after unblocking ignore it */ + set_handler(SIGIO, SIG_IGN, 0, -1); return(0); } Index: 2.6.9/arch/um/kernel/main.c =================================================================== --- 2.6.9.orig/arch/um/kernel/main.c 2004-11-24 12:23:13.000000000 -0500 +++ 2.6.9/arch/um/kernel/main.c 2004-11-24 12:29:36.000000000 -0500 @@ -155,18 +155,20 @@ int err; printf("\n"); - - /* Let any pending signals fire, then disable them. This - * ensures that they won't be delivered after the exec, when - * they are definitely not expected. - */ - unblock_signals(); + /* stop timers and set SIG*ALRM to be ignored */ disable_timer(); + /* disable SIGIO for the fds and set SIGIO to be ignored */ err = deactivate_all_fds(); if(err) printf("deactivate_all_fds failed, errno = %d\n", -err); + /* Let any pending signals fire now. This ensures + * that they won't be delivered after the exec, when + * they are definitely not expected. + */ + unblock_signals(); + execvp(new_argv[0], new_argv); perror("Failed to exec kernel"); ret = 1; Index: 2.6.9/arch/um/kernel/time.c =================================================================== --- 2.6.9.orig/arch/um/kernel/time.c 2004-11-24 12:23:12.000000000 -0500 +++ 2.6.9/arch/um/kernel/time.c 2004-11-24 12:29:36.000000000 -0500 @@ -60,6 +60,9 @@ (setitimer(ITIMER_REAL, &disable, NULL) < 0)) printk("disnable_timer - setitimer failed, errno = %d\n", errno); + /* If there are signals already queued, after unblocking ignore them */ + set_handler(SIGALRM, SIG_IGN, 0, -1); + set_handler(SIGVTALRM, SIG_IGN, 0, -1); } void switch_timers(int to_real)