xen/events: fix error codes in xen_bind_pirq_msi_to_irq()

[PATCH] xen/events: fix error codes in xen_bind_pirq_msi_to_irq()

Posted by Dan Carpenter 1 year, 11 months ago

The error code needs to be set on these error paths.

Fixes: 5dd9ad32d775 ("xen/events: drop xen_allocate_irqs_dynamic()")
Fixes: d2ba3166f23b ("xen/events: move drivers/xen/events.c into drivers/xen/events/")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
---
Are we going to backport these to stable?  Should I split this into two
patches?

 drivers/xen/events/events_base.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c
index f5edb9e27e3c..aae62603b461 100644
--- a/drivers/xen/events/events_base.c
+++ b/drivers/xen/events/events_base.c
@@ -1105,13 +1105,17 @@ int xen_bind_pirq_msi_to_irq(struct pci_dev *dev, struct msi_desc *msidesc,
 	mutex_lock(&irq_mapping_update_lock);
 
 	irq = irq_alloc_descs(-1, 0, nvec, -1);
-	if (irq < 0)
+	if (irq < 0) {
+		ret = irq;
 		goto out;
+	}
 
 	for (i = 0; i < nvec; i++) {
 		info = xen_irq_init(irq + i);
-		if (!info)
+		if (!info) {
+			ret = -ENOMEM;
 			goto error_irq;
+		}
 
 		irq_set_chip_and_handler_name(irq + i, &xen_pirq_chip, handle_edge_irq, name);
 
-- 
2.42.0

Re: [PATCH] xen/events: fix error codes in xen_bind_pirq_msi_to_irq()

Posted by Juergen Gross 1 year, 11 months ago

On 27.11.23 13:57, Dan Carpenter wrote:
> The error code needs to be set on these error paths.
> 
> Fixes: 5dd9ad32d775 ("xen/events: drop xen_allocate_irqs_dynamic()")
> Fixes: d2ba3166f23b ("xen/events: move drivers/xen/events.c into drivers/xen/events/")

Please drop the last Fixes: tag. Said patch didn't introduce any new problem.

> Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
> ---
> Are we going to backport these to stable?  Should I split this into two
> patches?
> 
>   drivers/xen/events/events_base.c | 8 ++++++--
>   1 file changed, 6 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c
> index f5edb9e27e3c..aae62603b461 100644
> --- a/drivers/xen/events/events_base.c
> +++ b/drivers/xen/events/events_base.c
> @@ -1105,13 +1105,17 @@ int xen_bind_pirq_msi_to_irq(struct pci_dev *dev, struct msi_desc *msidesc,
>   	mutex_lock(&irq_mapping_update_lock);
>   
>   	irq = irq_alloc_descs(-1, 0, nvec, -1);
> -	if (irq < 0)
> +	if (irq < 0) {
> +		ret = irq;
>   		goto out;
> +	}

Why? The return value for the out: label is in irq.

>   
>   	for (i = 0; i < nvec; i++) {
>   		info = xen_irq_init(irq + i);
> -		if (!info)
> +		if (!info) {
> +			ret = -ENOMEM;
>   			goto error_irq;
> +		}

It would be easier to just preset ret with -ENOMEM when defining it.


Juergen

Re: [PATCH] xen/events: fix error codes in xen_bind_pirq_msi_to_irq()

Posted by Dan Carpenter 1 year, 11 months ago

On Mon, Nov 27, 2023 at 02:17:05PM +0100, Juergen Gross wrote:
> On 27.11.23 13:57, Dan Carpenter wrote:
> > The error code needs to be set on these error paths.
> > 
> > Fixes: 5dd9ad32d775 ("xen/events: drop xen_allocate_irqs_dynamic()")
> > Fixes: d2ba3166f23b ("xen/events: move drivers/xen/events.c into drivers/xen/events/")
> 
> Please drop the last Fixes: tag. Said patch didn't introduce any new problem.

Yup.

> 
> > Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
> > ---
> > Are we going to backport these to stable?  Should I split this into two
> > patches?
> > 
> >   drivers/xen/events/events_base.c | 8 ++++++--
> >   1 file changed, 6 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c
> > index f5edb9e27e3c..aae62603b461 100644
> > --- a/drivers/xen/events/events_base.c
> > +++ b/drivers/xen/events/events_base.c
> > @@ -1105,13 +1105,17 @@ int xen_bind_pirq_msi_to_irq(struct pci_dev *dev, struct msi_desc *msidesc,
> >   	mutex_lock(&irq_mapping_update_lock);
> >   	irq = irq_alloc_descs(-1, 0, nvec, -1);
> > -	if (irq < 0)
> > +	if (irq < 0) {
> > +		ret = irq;
> >   		goto out;
> > +	}
> 
> Why? The return value for the out: label is in irq.
> 

This patch is full of embarrassment.  I misread this code.  I thought
the out label was in the error handling block.

> >   	for (i = 0; i < nvec; i++) {
> >   		info = xen_irq_init(irq + i);
> > -		if (!info)
> > +		if (!info) {
> > +			ret = -ENOMEM;
> >   			goto error_irq;
> > +		}
> 
> It would be easier to just preset ret with -ENOMEM when defining it.
> 

That only works if it fails on the first iteration.

I'll fix this up and resend.

regards,
dan carpenter