2024-04-19 14:12:58

by Markus Elfring

[permalink] [raw]
Subject: [PATCH] ibmvnic: Use -EBUSY in __ibmvnic_reset()

From: Markus Elfring <[email protected]>
Date: Fri, 19 Apr 2024 15:46:17 +0200

Add a minus sign before the error code “EBUSY”
so that a negative value will be used as in other cases.

This issue was transformed by using the Coccinelle software.

Signed-off-by: Markus Elfring <[email protected]>
---
drivers/net/ethernet/ibm/ibmvnic.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
index 5e9a93bdb518..737ae83a836a 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -3212,7 +3212,7 @@ static void __ibmvnic_reset(struct work_struct *work)
adapter->state == VNIC_REMOVED) {
spin_unlock_irqrestore(&adapter->state_lock, flags);
kfree(rwi);
- rc = EBUSY;
+ rc = -EBUSY;
break;
}

--
2.44.0



2024-04-23 11:03:41

by Paolo Abeni

[permalink] [raw]
Subject: Re: [PATCH] ibmvnic: Use -EBUSY in __ibmvnic_reset()

On Fri, 2024-04-19 at 16:08 +0200, Markus Elfring wrote:
> From: Markus Elfring <[email protected]>
> Date: Fri, 19 Apr 2024 15:46:17 +0200
>
> Add a minus sign before the error code “EBUSY”
> so that a negative value will be used as in other cases.
>
> This issue was transformed by using the Coccinelle software.
>
> Signed-off-by: Markus Elfring <[email protected]>
> ---
> drivers/net/ethernet/ibm/ibmvnic.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
> index 5e9a93bdb518..737ae83a836a 100644
> --- a/drivers/net/ethernet/ibm/ibmvnic.c
> +++ b/drivers/net/ethernet/ibm/ibmvnic.c
> @@ -3212,7 +3212,7 @@ static void __ibmvnic_reset(struct work_struct *work)
> adapter->state == VNIC_REMOVED) {
> spin_unlock_irqrestore(&adapter->state_lock, flags);
> kfree(rwi);
> - rc = EBUSY;
> + rc = -EBUSY;
> break;
>

AFAICS the error is always used as bool, so this will not change any
behavior in practice. I tend to think we should not merge this kind of
change outside some larger work in the same area, but I'd love a second
opinion from the driver owners.

Thanks,

Paolo
> }



2024-04-23 12:04:52

by Dan Carpenter

[permalink] [raw]
Subject: Re: [PATCH] ibmvnic: Use -EBUSY in __ibmvnic_reset()

On Tue, Apr 23, 2024 at 12:54:55PM +0200, Paolo Abeni wrote:
> On Fri, 2024-04-19 at 16:08 +0200, Markus Elfring wrote:
> > From: Markus Elfring <[email protected]>
> > Date: Fri, 19 Apr 2024 15:46:17 +0200
> >
> > Add a minus sign before the error code “EBUSY”
> > so that a negative value will be used as in other cases.
> >
> > This issue was transformed by using the Coccinelle software.
> >
> > Signed-off-by: Markus Elfring <[email protected]>
> > ---
> > drivers/net/ethernet/ibm/ibmvnic.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
> > index 5e9a93bdb518..737ae83a836a 100644
> > --- a/drivers/net/ethernet/ibm/ibmvnic.c
> > +++ b/drivers/net/ethernet/ibm/ibmvnic.c
> > @@ -3212,7 +3212,7 @@ static void __ibmvnic_reset(struct work_struct *work)
> > adapter->state == VNIC_REMOVED) {
> > spin_unlock_irqrestore(&adapter->state_lock, flags);
> > kfree(rwi);
> > - rc = EBUSY;
> > + rc = -EBUSY;
> > break;
> >
>
> AFAICS the error is always used as bool, so this will not change any
> behavior in practice. I tend to think we should not merge this kind of
> change outside some larger work in the same area, but I'd love a second
> opinion from the driver owners.

I missed the original patch due to my procmail filters...

You're right that it doesn't affect the behavior of the driver except
for the debug output when we do:

netdev_dbg(adapter->netdev, "Reset failed, rc=%d\n", rc);

But the - was left off uninitentionally so I think we should apply it.

I have been trying to look for similar bugs where the - is left off.
It's a bit challenging because there places where we use positive
error codes deliberately. But in this case a static checker could
easily detect the bug with a low false positive ratio by saying, "We're
mixing normal negative error codes with positive EBUSY".

regards,
dan carpenter

2024-04-23 14:57:13

by Nick Child

[permalink] [raw]
Subject: Re: [PATCH] ibmvnic: Use -EBUSY in __ibmvnic_reset()



On 4/23/24 06:55, Dan Carpenter wrote:
> On Tue, Apr 23, 2024 at 12:54:55PM +0200, Paolo Abeni wrote:
>> On Fri, 2024-04-19 at 16:08 +0200, Markus Elfring wrote:
>>> From: Markus Elfring <[email protected]>
>>> Date: Fri, 19 Apr 2024 15:46:17 +0200
>>>
>>> Add a minus sign before the error code “EBUSY”
>>> so that a negative value will be used as in other cases.
>>>
>>> This issue was transformed by using the Coccinelle software.
>>>
>>> Signed-off-by: Markus Elfring <[email protected]>
>>> ---
>>> drivers/net/ethernet/ibm/ibmvnic.c | 2 +-
>>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
>>> index 5e9a93bdb518..737ae83a836a 100644
>>> --- a/drivers/net/ethernet/ibm/ibmvnic.c
>>> +++ b/drivers/net/ethernet/ibm/ibmvnic.c
>>> @@ -3212,7 +3212,7 @@ static void __ibmvnic_reset(struct work_struct *work)
>>> adapter->state == VNIC_REMOVED) {
>>> spin_unlock_irqrestore(&adapter->state_lock, flags);
>>> kfree(rwi);
>>> - rc = EBUSY;
>>> + rc = -EBUSY;
>>> break;
>>>
>>
>> AFAICS the error is always used as bool, so this will not change any
>> behavior in practice. I tend to think we should not merge this kind of
>> change outside some larger work in the same area, but I'd love a second
>> opinion from the driver owners.
>
> I missed the original patch due to my procmail filters...
>
> You're right that it doesn't affect the behavior of the driver except
> for the debug output when we do:
>
> netdev_dbg(adapter->netdev, "Reset failed, rc=%d\n", rc);
>
> But the - was left off uninitentionally so I think we should apply it.
>
> I have been trying to look for similar bugs where the - is left off.
> It's a bit challenging because there places where we use positive
> error codes deliberately. But in this case a static checker could
> easily detect the bug with a low false positive ratio by saying, "We're
> mixing normal negative error codes with positive EBUSY".
>
> regards,
> dan carpenter

Hello, small clarification, this patch will not effect the debug print
statement due to the break statement immediately following:
while () {
if () {
rc = -EBUSY;
break;
}
netdev_dbg(adapter->netdev, "Reset failed, rc=%d\n", rc);
}
Though this return code can be passed to adapter->reset_done_rc, which
is only treated as a boolean.

So, the point of the patch not doing any behavioral differences is still
true.
Personally, I don't have strong opinions on this.
Reviewed-by: Nick Child <[email protected]>

2024-04-23 15:42:34

by Dan Carpenter

[permalink] [raw]
Subject: Re: [PATCH] ibmvnic: Use -EBUSY in __ibmvnic_reset()

On Tue, Apr 23, 2024 at 09:55:57AM -0500, Nick Child wrote:
> > You're right that it doesn't affect the behavior of the driver except
> > for the debug output when we do:
> >
> > netdev_dbg(adapter->netdev, "Reset failed, rc=%d\n", rc);
> >
> > But the - was left off uninitentionally so I think we should apply it.
> >
> > I have been trying to look for similar bugs where the - is left off.
> > It's a bit challenging because there places where we use positive
> > error codes deliberately. But in this case a static checker could
> > easily detect the bug with a low false positive ratio by saying, "We're
> > mixing normal negative error codes with positive EBUSY".
> >
> > regards,
> > dan carpenter
>
> Hello, small clarification, this patch will not effect the debug print
> statement due to the break statement immediately following:
> while () {
> if () {
> rc = -EBUSY;
> break;
> }
> netdev_dbg(adapter->netdev, "Reset failed, rc=%d\n", rc);
> }
> Though this return code can be passed to adapter->reset_done_rc, which is
> only treated as a boolean.
>
> So, the point of the patch not doing any behavioral differences is still
> true.

Ah yes. You're right.

regards,
dan carpenter


2024-04-25 02:32:44

by Jakub Kicinski

[permalink] [raw]
Subject: Re: [PATCH] ibmvnic: Use -EBUSY in __ibmvnic_reset()

On Tue, 23 Apr 2024 18:41:48 +0300 Dan Carpenter wrote:
> > So, the point of the patch not doing any behavioral differences is still
> > true.
>
> Ah yes. You're right.

Hard call but overall I think this wasted more reviewer time than it's
worth. So in the spirit of not encouraging noise I'm not applying this.
--
pw-bot: reject