From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from s3.sipsolutions.net ([2a01:4f8:191:4433::2] helo=sipsolutions.net) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lHTqx-005UJN-KI for linux-um@lists.infradead.org; Wed, 03 Mar 2021 15:56:05 +0000 From: Benjamin Berg Subject: [PATCH 08/27] um: Reap winch thread if it fails Date: Wed, 3 Mar 2021 16:55:04 +0100 Message-Id: <20210303155523.124277-9-benjamin@sipsolutions.net> In-Reply-To: <20210303155523.124277-1-benjamin@sipsolutions.net> References: <20210303155523.124277-1-benjamin@sipsolutions.net> MIME-Version: 1.0 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-um" Errors-To: linux-um-bounces+geert=linux-m68k.org@lists.infradead.org To: linux-um@lists.infradead.org Cc: Benjamin Berg When the winch thread runs into an error condition, it would exit(1) and never be reaped until shutdown time. Change this to write a command byte which causes the driver to kill it, therefore reaping the child. Signed-off-by: Benjamin Berg --- arch/um/drivers/chan_user.c | 15 ++++++++++----- arch/um/drivers/line.c | 13 ++++++++----- 2 files changed, 18 insertions(+), 10 deletions(-) diff --git a/arch/um/drivers/chan_user.c b/arch/um/drivers/chan_user.c index 9d87c9998741..57547bdcb5c6 100644 --- a/arch/um/drivers/chan_user.c +++ b/arch/um/drivers/chan_user.c @@ -141,7 +141,7 @@ struct winch_data { int pipe_fd; }; -static int winch_thread(void *arg) +static __noreturn int winch_thread(void *arg) { struct winch_data *data = arg; sigset_t sigs; @@ -168,7 +168,7 @@ static int winch_thread(void *arg) if (sigprocmask(SIG_SETMASK, &sigs, NULL) < 0) { os_info("winch_thread : sigprocmask failed, errno = %d\n", errno); - exit(1); + goto wait_kill; } /* In sigsuspend(), block anything else than SIGWINCH. */ sigdelset(&sigs, SIGWINCH); @@ -176,19 +176,19 @@ static int winch_thread(void *arg) if (setsid() < 0) { os_info("winch_thread : setsid failed, errno = %d\n", errno); - exit(1); + goto wait_kill; } if (ioctl(pty_fd, TIOCSCTTY, 0) < 0) { os_info("winch_thread : TIOCSCTTY failed on " "fd %d err = %d\n", pty_fd, errno); - exit(1); + goto wait_kill; } if (tcsetpgrp(pty_fd, os_getpid()) < 0) { os_info("winch_thread : tcsetpgrp failed on fd %d err = %d\n", pty_fd, errno); - exit(1); + goto wait_kill; } /* @@ -214,6 +214,11 @@ static int winch_thread(void *arg) os_info("winch_thread : write failed, err = %d\n", errno); } + +wait_kill: + c = 2; + count = write(pipe_fd, &c, sizeof(c)); + while (1) { pause(); }; } static int winch_tramp(int fd, struct tty_port *port, int *fd_out, diff --git a/arch/um/drivers/line.c b/arch/um/drivers/line.c index 1c70a31e7c5b..b2800a085a3b 100644 --- a/arch/um/drivers/line.c +++ b/arch/um/drivers/line.c @@ -629,15 +629,18 @@ static irqreturn_t winch_interrupt(int irq, void *data) if (fd != -1) { err = generic_read(fd, &c, NULL); - if (err < 0) { + /* A read of 2 means the winch thread failed and has warned */ + if (err < 0 || (err = 1 && c == 2)) { if (err != -EAGAIN) { winch->fd = -1; list_del(&winch->list); os_close_file(fd); - printk(KERN_ERR "winch_interrupt : " - "read failed, errno = %d\n", -err); - printk(KERN_ERR "fd %d is losing SIGWINCH " - "support\n", winch->tty_fd); + if (err < 0) { + printk(KERN_ERR "winch_interrupt : read failed, errno = %d\n", + -err); + printk(KERN_ERR "fd %d is losing SIGWINCH support\n", + winch->tty_fd); + } INIT_WORK(&winch->work, __free_winch); schedule_work(&winch->work); return IRQ_HANDLED; -- 2.29.2 _______________________________________________ linux-um mailing list linux-um@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-um