Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758761AbXFMOoB (ORCPT ); Wed, 13 Jun 2007 10:44:01 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758504AbXFMOnf (ORCPT ); Wed, 13 Jun 2007 10:43:35 -0400 Received: from saraswathi.solana.com ([198.99.130.12]:55902 "EHLO saraswathi.solana.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758179AbXFMOne (ORCPT ); Wed, 13 Jun 2007 10:43:34 -0400 Date: Wed, 13 Jun 2007 10:42:45 -0400 From: Jeff Dike To: Andrew Morton Cc: Eduard-Gabriel Munteanu , LKML , uml-devel Subject: [PATCH 1/2] UML - DEBUG_SHIRQ fixes Message-ID: <20070613144245.GA5777@c2.user-mode-linux.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.4.2.3i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3749 Lines: 98 From: Eduard-Gabriel Munteanu DEBUG_SHIRQ generates spurious interrupts, triggering handlers such as mconsole_interrupt() or line_interrupt(). They expect data to be available to be read from their sockets/pipes, but in the case of spurious interrupts, the host didn't actually send anything, so UML hangs in read() and friends. Setting those fd's as O_NONBLOCK makes DEBUG_SHIRQ-enabled UML kernels boot and run correctly. The patch was written and tested on Linux 2.6.22-rc2-mm1. I have also included a couple of short/minor fixes for potential problems. Signed-off-by: Eduard-Gabriel Munteanu Signed-off-by: Jeff Dike -- arch/um/drivers/chan_user.c | 8 +++++++- arch/um/drivers/mconsole_user.c | 5 +++-- arch/um/drivers/ubd_user.c | 6 ++++++ arch/um/drivers/xterm.c | 7 +++++++ 4 files changed, 23 insertions(+), 3 deletions(-) Index: linux-2.6.21-mm/arch/um/drivers/chan_user.c =================================================================== --- linux-2.6.21-mm.orig/arch/um/drivers/chan_user.c 2007-06-06 09:28:13.000000000 -0400 +++ linux-2.6.21-mm/arch/um/drivers/chan_user.c 2007-06-11 13:51:29.000000000 -0400 @@ -170,7 +170,13 @@ static int winch_tramp(int fd, struct tt err = -EINVAL; goto out_close; } - return err ; + + if (os_set_fd_block(*fd_out, 0)) { + printk("winch_tramp: failed to set thread_fd non-blocking.\n"); + goto out_close; + } + + return err; out_close: os_close_file(fds[1]); Index: linux-2.6.21-mm/arch/um/drivers/mconsole_user.c =================================================================== --- linux-2.6.21-mm.orig/arch/um/drivers/mconsole_user.c 2007-06-06 09:28:13.000000000 -0400 +++ linux-2.6.21-mm/arch/um/drivers/mconsole_user.c 2007-06-11 13:38:19.000000000 -0400 @@ -86,8 +86,9 @@ int mconsole_get_request(int fd, struct int len; req->originlen = sizeof(req->origin); - req->len = recvfrom(fd, &req->request, sizeof(req->request), 0, - (struct sockaddr *) req->origin, &req->originlen); + req->len = recvfrom(fd, &req->request, sizeof(req->request), + MSG_DONTWAIT, (struct sockaddr *) req->origin, + &req->originlen); if (req->len < 0) return 0; Index: linux-2.6.21-mm/arch/um/drivers/ubd_user.c =================================================================== --- linux-2.6.21-mm.orig/arch/um/drivers/ubd_user.c 2007-06-06 09:28:13.000000000 -0400 +++ linux-2.6.21-mm/arch/um/drivers/ubd_user.c 2007-06-11 13:44:56.000000000 -0400 @@ -43,6 +43,12 @@ int start_io_thread(unsigned long sp, in kernel_fd = fds[0]; *fd_out = fds[1]; + err = os_set_fd_block(*fd_out, 0); + if (err) { + printk("start_io_thread - failed to set nonblocking I/O.\n"); + goto out_close; + } + pid = clone(io_thread, (void *) sp, CLONE_FILES | CLONE_VM | SIGCHLD, NULL); if(pid < 0){ Index: linux-2.6.21-mm/arch/um/drivers/xterm.c =================================================================== --- linux-2.6.21-mm.orig/arch/um/drivers/xterm.c 2007-06-06 09:28:13.000000000 -0400 +++ linux-2.6.21-mm/arch/um/drivers/xterm.c 2007-06-12 12:25:44.000000000 -0400 @@ -151,6 +151,13 @@ int xterm_open(int input, int output, in goto out; } + err = os_set_fd_block(new, 0); + if (err) { + printk("xterm_open : failed to set xterm descriptor " + "non-blocking, err = %d\n", -err); + goto out; + } + CATCH_EINTR(err = tcgetattr(new, &data->tt)); if(err){ new = err; - 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/