[PATCH net-next] ibmvnic: workaround QT Creator/libCPlusPlus segfault

[PATCH net-next] ibmvnic: workaround QT Creator/libCPlusPlus segfault

[Alexey Dobriyan]

My name is Alexey and I've tried to use IDE for kernel development.

QT Creator segfaults while parsing ibmvnic.c which is annoying as it
will start parsing after restart only to crash again.

The workaround is to either exclude ibmvnic.c from list of project files
or to apply dummy ifdef to hide the offending code.

https://bugzilla.redhat.com/show_bug.cgi?id=1886548

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
---

 drivers/net/ethernet/ibm/ibmvnic.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -5080,6 +5080,8 @@ static void ibmvnic_tasklet(struct tasklet_struct *t)
 	unsigned long flags;
 	bool done = false;
 
+	/* workaround QT Creator/libCPlusPlus.so segfault with dummy ifdef */
+#ifdef CONFIG_IBMVNIC
 	spin_lock_irqsave(&queue->lock, flags);
 	while (!done) {
 		/* Pull all the valid messages off the CRQ */
@@ -5100,6 +5102,7 @@ static void ibmvnic_tasklet(struct tasklet_struct *t)
 	if (atomic_read(&adapter->running_cap_crqs) != 0)
 		adapter->wait_capability = true;
 	spin_unlock_irqrestore(&queue->lock, flags);
+#endif
 }
 
 static int ibmvnic_reenable_crq_queue(struct ibmvnic_adapter *adapter)

[PATCH v2 net-next] ibmvnic: workaround QT Creator/libCPlusPlus segfault

[Alexey Dobriyan]

My name is Alexey and I've tried to use IDE for kernel development.

QT Creator segfaults while parsing ibmvnic.c which is annoying as it
will start parsing after restart only to crash again.

The workaround is to either exclude ibmvnic.c from list of project files
or to apply dummy ifdef to hide the offending code.

https://bugzilla.redhat.com/show_bug.cgi?id=1886548

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
---

	fix modular case

 drivers/net/ethernet/ibm/ibmvnic.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -5080,6 +5080,8 @@ static void ibmvnic_tasklet(struct tasklet_struct *t)
 	unsigned long flags;
 	bool done = false;
 
+	/* workaround QT Creator/libCPlusPlus.so segfault with dummy if */
+#if IS_ENABLED(CONFIG_IBMVNIC)
 	spin_lock_irqsave(&queue->lock, flags);
 	while (!done) {
 		/* Pull all the valid messages off the CRQ */
@@ -5100,6 +5102,7 @@ static void ibmvnic_tasklet(struct tasklet_struct *t)
 	if (atomic_read(&adapter->running_cap_crqs) != 0)
 		adapter->wait_capability = true;
 	spin_unlock_irqrestore(&queue->lock, flags);
+#endif
 }
 
 static int ibmvnic_reenable_crq_queue(struct ibmvnic_adapter *adapter)

Re: [PATCH net-next] ibmvnic: workaround QT Creator/libCPlusPlus segfault

[Andrew Lunn]

On Fri, Jan 22, 2021 at 01:01:50AM +0300, Alexey Dobriyan wrote:
> My name is Alexey and I've tried to use IDE for kernel development.
> 
> QT Creator segfaults while parsing ibmvnic.c which is annoying as it
> will start parsing after restart only to crash again.
> 
> The workaround is to either exclude ibmvnic.c from list of project files
> or to apply dummy ifdef to hide the offending code.
> 
> https://bugzilla.redhat.com/show_bug.cgi?id=1886548

Sorry, but this is not going to be accepted.

Can you narrow it down further. In bugzilla, you say the includes are
wrong. How exactly?

       Andrew

Re: [PATCH v2 net-next] ibmvnic: workaround QT Creator/libCPlusPlus segfault

[Jakub Kicinski]

On Fri, 22 Jan 2021 01:07:39 +0300 Alexey Dobriyan wrote:
> My name is Alexey and I've tried to use IDE for kernel development.
> 
> QT Creator segfaults while parsing ibmvnic.c which is annoying as it
> will start parsing after restart only to crash again.
> 
> The workaround is to either exclude ibmvnic.c from list of project files
> or to apply dummy ifdef to hide the offending code.
> 
> https://bugzilla.redhat.com/show_bug.cgi?id=1886548
> 
> Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>

That's a bug in QT Creator and whatever parsing it does/uses.

Sorry we can't take this patch, there is no indication that the kernel
code is actually wrong here.

Re: [PATCH v2 net-next] ibmvnic: workaround QT Creator/libCPlusPlus segfault

[Alexey Dobriyan]

On Thu, Jan 21, 2021 at 06:44:54PM -0800, Jakub Kicinski wrote:
> On Fri, 22 Jan 2021 01:07:39 +0300 Alexey Dobriyan wrote:
> > My name is Alexey and I've tried to use IDE for kernel development.
> > 
> > QT Creator segfaults while parsing ibmvnic.c which is annoying as it
> > will start parsing after restart only to crash again.
> > 
> > The workaround is to either exclude ibmvnic.c from list of project files
> > or to apply dummy ifdef to hide the offending code.
> > 
> > https://bugzilla.redhat.com/show_bug.cgi?id=1886548
> > 
> > Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
> 
> That's a bug in QT Creator and whatever parsing it does/uses.
> 
> Sorry we can't take this patch, there is no indication that the kernel
> code is actually wrong here.

It is QtC bug. It will take ages for distros to pick up the fix
(which doesn't even exist probably).