um: Reap winch thread if it fails

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 <benjamin@sipsolutions.net>
Signed-off-by: Richard Weinberger <richard@nod.at>
This commit is contained in:
Benjamin Berg 2023-11-10 12:03:43 +01:00 committed by Richard Weinberger
parent 1818b84066
commit 139e6e8ef6
2 changed files with 19 additions and 10 deletions

View File

@ -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 +214,12 @@ 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,

View File

@ -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;