Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763812AbXFJXAG (ORCPT ); Sun, 10 Jun 2007 19:00:06 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1760205AbXFJW74 (ORCPT ); Sun, 10 Jun 2007 18:59:56 -0400 Received: from max.aladin.ro ([80.96.155.2]:58751 "EHLO aladin.ro" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759215AbXFJW7z (ORCPT ); Sun, 10 Jun 2007 18:59:55 -0400 Subject: [PATCH 1/1] UML: fix missing non-blocking I/O, now DEBUG_SHIRQ works From: Eduard-Gabriel Munteanu To: jdike@karaya.com Cc: linux-kernel@vger.kernel.org Content-Type: text/plain Date: Mon, 11 Jun 2007 01:01:57 +0300 Message-Id: <1181512917.3157.8.camel@localhost> Mime-Version: 1.0 X-Mailer: Evolution 2.8.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4562 Lines: 139 *This message was transferred with a trial version of CommuniGate(r) Pro* 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 --- arch/um/drivers/chan_user.c | 6 ++++++ arch/um/drivers/mconsole_kern.c | 11 +++++------ arch/um/drivers/mconsole_user.c | 5 +++-- arch/um/drivers/ubd_user.c | 6 ++++++ arch/um/drivers/xterm.c | 7 +++++++ 5 files changed, 27 insertions(+), 8 deletions(-) diff --git a/arch/um/drivers/chan_user.c b/arch/um/drivers/chan_user.c index 13f0bf8..0a8b785 100644 --- a/arch/um/drivers/chan_user.c +++ b/arch/um/drivers/chan_user.c @@ -170,6 +170,12 @@ static int winch_tramp(int fd, struct tty_struct *tty, int *fd_out) err = -EINVAL; goto out_close; } + + 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: diff --git a/arch/um/drivers/mconsole_kern.c b/arch/um/drivers/mconsole_kern.c index 542c9ef..02d132e 100644 --- a/arch/um/drivers/mconsole_kern.c +++ b/arch/um/drivers/mconsole_kern.c @@ -74,12 +74,11 @@ static DECLARE_WORK(mconsole_work, mc_work_proc); static irqreturn_t mconsole_interrupt(int irq, void *dev_id) { - /* long to avoid size mismatch warnings from gcc */ - long fd; + int fd; struct mconsole_entry *new; static struct mc_request req; /* that's OK */ - fd = (long) dev_id; + fd = *((int *) dev_id); while (mconsole_get_request(fd, &req)){ if(req.cmd->context == MCONSOLE_INTR) (*req.cmd->handler)(&req); @@ -798,10 +797,10 @@ void mconsole_stack(struct mc_request *req) */ static char *notify_socket = NULL; +static int sock; + static int mconsole_init(void) { - /* long to avoid size mismatch warnings from gcc */ - long sock; int err; char file[256]; @@ -818,7 +817,7 @@ static int mconsole_init(void) err = um_request_irq(MCONSOLE_IRQ, sock, IRQ_READ, mconsole_interrupt, IRQF_DISABLED | IRQF_SHARED | IRQF_SAMPLE_RANDOM, - "mconsole", (void *)sock); + "mconsole", &sock); if (err){ printk("Failed to get IRQ for management console\n"); return(1); diff --git a/arch/um/drivers/mconsole_user.c b/arch/um/drivers/mconsole_user.c index 62e5ad6..f31e715 100644 --- a/arch/um/drivers/mconsole_user.c +++ b/arch/um/drivers/mconsole_user.c @@ -86,8 +86,9 @@ int mconsole_get_request(int fd, struct mc_request *req) 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; diff --git a/arch/um/drivers/ubd_user.c b/arch/um/drivers/ubd_user.c index 4707b3f..56f2c23 100644 --- a/arch/um/drivers/ubd_user.c +++ b/arch/um/drivers/ubd_user.c @@ -43,6 +43,12 @@ int start_io_thread(unsigned long sp, int *fd_out) 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){ diff --git a/arch/um/drivers/xterm.c b/arch/um/drivers/xterm.c index 571c2b3..2b65b57 100644 --- a/arch/um/drivers/xterm.c +++ b/arch/um/drivers/xterm.c @@ -151,6 +151,13 @@ int xterm_open(int input, int output, int primary, void *d, 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); + return(err); + } + 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/