Re: khubd zombie

[Patrik Weiskircher]

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On Mon, 2002-02-18 at 19:14, Greg KH wrote:
> On Mon, Feb 18, 2002 at 02:33:13PM +0100, Patrik Weiskircher wrote:
> > killall khubd results to:
> > 10 ?        Z      0:00 [khubd <defunct>]
> > 
> > is this ok?
> > if not, how can i solve this?
> 
> What kernel version is this?
> And why are you trying to kill khubd from userspace?  Unloading the
> usbcore module will do the same thing.
> 
> thanks,
> 
> greg k-h

I tried it with 2.4.5, 2.4.12, 2.4.17.
And I have to kill everything except init.
I need a "clean" system.

Anyway, I don't think that it should behave like that.
Killing something from userspace should not affect the kernel, or did I
miss something?

I fixed it, it works, patch file attached.

Best Regards,
Patrik

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diff -Naur linux-2.4.17/drivers/usb/hub.c linux/drivers/usb/hub.c
--- linux-2.4.17/drivers/usb/hub.c	Mon Feb 18 20:43:48 2002
+++ linux/drivers/usb/hub.c	Mon Feb 18 20:38:50 2002
@@ -826,6 +826,8 @@
=20
 static int usb_hub_thread(void *__hub)
 {
+	struct task_struct *tsk =3D current;
+
 	lock_kernel();
=20
 	/*
@@ -835,6 +837,13 @@
=20
 	daemonize();
=20
+	/* avoid getting signals */
+	spin_lock_irq(&tsk->sigmask_lock);
+	flush_signals(tsk);
+	sigfillset(&tsk->blocked);
+	recalc_sigpending(tsk);
+	spin_unlock_irq(&tsk->sigmask_lock);
+
 	/* Setup a nice name */
 	strcpy(current->comm, "khubd");
=20
@@ -879,7 +888,7 @@
 	}
=20
 	pid =3D kernel_thread(usb_hub_thread, NULL,
-		CLONE_FS | CLONE_FILES | CLONE_SIGHAND);
+		CLONE_FS | CLONE_FILES | CLONE_SIGNAL);
 	if (pid >=3D 0) {
 		khubd_pid =3D pid;
=20

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