From 89df6bfc04059716de2eb2fe529f05b3e124fafd Mon Sep 17 00:00:00 2001 From: Eduard-Gabriel Munteanu Date: Sun, 15 Jul 2007 23:38:51 -0700 Subject: [PATCH] uml: DEBUG_SHIRQ fixes 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. Signed-off-by: Eduard-Gabriel Munteanu Signed-off-by: Jeff Dike Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- 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(-) diff --git a/arch/um/drivers/chan_user.c b/arch/um/drivers/chan_user.c index 13f0bf8..5d1289d 100644 --- a/arch/um/drivers/chan_user.c +++ b/arch/um/drivers/chan_user.c @@ -170,7 +170,13 @@ static int winch_tramp(int fd, struct tty_struct *tty, int *fd_out) 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]); 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..41d254b 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..fe238e0 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); + goto out; + } + CATCH_EINTR(err = tcgetattr(new, &data->tt)); if(err){ new = err; -- 2.7.4