iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

fix spinlock recursion in hvc_console

Browse Source 
commit 611e097d77
Author: Christian Borntraeger <borntraeger@de.ibm.com>
hvc_console: rework setup to replace irq functions with callbacks
introduced a spinlock recursion problem.

request_irq tries to call the handler if the IRQ is shared.
The irq handler of hvc_console calls hvc_poll and hvc_kill
which might take the hvc_struct spinlock. Therefore, we have
to call request_irq outside the spinlock.

We can move the notifier_add safely outside the spinlock as ->data must
not be changed by the backend. Otherwise, tty_hangup would fail anyway.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This commit is contained in:
Christian Borntraeger 2008-08-07 09:18:34 +02:00 committed by Rusty Russell
parent ed6d68763b
commit b1b135c8d6
1 changed files with 2 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
drivers/char/hvc_console.c
View File

@ -322,11 +322,10 @@ static int hvc_open(struct tty_struct *tty, struct file * filp)
hp->tty = tty;
if (hp->ops->notifier_add)
rc = hp->ops->notifier_add(hp, hp->data);
spin_unlock_irqrestore(&hp->lock, flags);
if (hp->ops->notifier_add)
rc = hp->ops->notifier_add(hp, hp->data);
/*
* If the notifier fails we return an error. The tty layer