mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-26 02:39:48 +00:00
tty/hvc: Use IRQF_SHARED for OPAL hvc consoles
Commit 2def86a720
("hvc: Convert to using interrupts instead of opal
events") enabled the use of interrupts in the hvc_driver for OPAL
platforms. However on machines with more than one hvc console, any
console after the first will fail to register an interrupt handler in
notifier_add_irq() since all consoles share the same IRQ number but do
not set the IRQF_SHARED flag:
genirq: Flags mismatch irq 31. 00000000 (hvc_console) vs. 00000000 (hvc_console)
hvc_open: request_irq failed with rc -16.
This error propagates up to hvc_open() and the console is closed, but
OPAL will still generate interrupts that are not handled, leading to
rcu_sched stall warnings.
Set IRQF_SHARED when calling request_irq(), allowing additional consoles
to start properly. This is only set for consoles handled by
hvc_opal_probe(), leaving other types unaffected.
Signed-off-by: Samuel Mendoza-Jonas <sam@mendozajonas.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
parent
a431b946db
commit
bbc3dfe880
3 changed files with 11 additions and 2 deletions
|
@ -60,6 +60,7 @@ struct hvc_struct {
|
|||
struct winsize ws;
|
||||
struct work_struct tty_resize;
|
||||
struct list_head next;
|
||||
unsigned long flags;
|
||||
};
|
||||
|
||||
/* implemented by a low level driver */
|
||||
|
|
|
@ -14,6 +14,11 @@ static irqreturn_t hvc_handle_interrupt(int irq, void *dev_instance)
|
|||
/* if hvc_poll request a repoll, then kick the hvcd thread */
|
||||
if (hvc_poll(dev_instance))
|
||||
hvc_kick();
|
||||
|
||||
/*
|
||||
* We're safe to always return IRQ_HANDLED as the hvcd thread will
|
||||
* iterate through each hvc_struct.
|
||||
*/
|
||||
return IRQ_HANDLED;
|
||||
}
|
||||
|
||||
|
@ -28,8 +33,8 @@ int notifier_add_irq(struct hvc_struct *hp, int irq)
|
|||
hp->irq_requested = 0;
|
||||
return 0;
|
||||
}
|
||||
rc = request_irq(irq, hvc_handle_interrupt, 0,
|
||||
"hvc_console", hp);
|
||||
rc = request_irq(irq, hvc_handle_interrupt, hp->flags,
|
||||
"hvc_console", hp);
|
||||
if (!rc)
|
||||
hp->irq_requested = 1;
|
||||
return rc;
|
||||
|
|
|
@ -224,6 +224,9 @@ static int hvc_opal_probe(struct platform_device *dev)
|
|||
hp = hvc_alloc(termno, irq, ops, MAX_VIO_PUT_CHARS);
|
||||
if (IS_ERR(hp))
|
||||
return PTR_ERR(hp);
|
||||
|
||||
/* hvc consoles on powernv may need to share a single irq */
|
||||
hp->flags = IRQF_SHARED;
|
||||
dev_set_drvdata(&dev->dev, hp);
|
||||
|
||||
return 0;
|
||||
|
|
Loading…
Reference in a new issue