diff mbox

PCI: pcie-rcar: Fix OF node passed to MSI irq domain

Message ID 564EECA9.9070400@arm.com
State Superseded
Headers show

Commit Message

Marc Zyngier Nov. 20, 2015, 9:49 a.m. UTC
On 18/11/15 18:01, Phil Edworthy wrote:
> Hi Marc,
> 
> On 16 November 2015 18:31, Marc Zyngier wrote:
>> On 13/11/15 09:36, Phil Edworthy wrote:
> <snip>
>>> Since the stack trace doesn't help that much I added some tracing:
>>> pci_msi_setup_msi_irqs()
>>>   calls pci_msi_get_domain()
>>>     calls dev_get_msi_domain(), gets a non-NULL domain.
>>> pci_msi_setup_msi_irqs()
>>>   calls pci_msi_domain_alloc_irqs()
>>>     calls msi_domain_alloc_irqs()
>>> msi_domain_alloc_irqs:273: ops=ffffffc03193a810
>>> msi_domain_alloc_irqs:274: ops->msi_check=ffffffc031161418
>>> systemd-udevd[1311]: undefined instruction: pc=ffffffc03116141c
>>> That looks to me as though msi_check is off pointing to the weeds.
>>
>> So the next step is to find out who initializes msi_check. Assuming
>> someone does...
> Nothing initializes msi_check... 
> 
>  
>>> By passing a NULL domain into irq_domain_add_linear() you get:
>>> pci_msi_setup_msi_irqs()
>>>   calls pci_msi_get_domain()
>>>     calls dev_get_msi_domain(), gets a NULL domain.
>>>     calls arch_setup_msi_irq()
>>> All ok then.
>>
>> Yes, because you're sidestepping the issue. Any chance you could dig a
>> bit deeper? I'd really like to nail this one down (before we convert
>> your PCI driver to the right API... ;-).
> The problem appears to be that when the pci host driver enables msi
> it calls the following:
> 	msi->domain = irq_domain_add_linear(pcie->dev->of_node, INT_PCI_MSI_NR,
> 					    &msi_domain_ops, &msi->chip);
> The last arg is documented as:
> * @host_data: Controller private data pointer 
> In _irq_domain_add() this ptr is stored in struct irq_domain's host_data.
> 
> However, msi_domain_alloc_irqs() expects host_data to be a ptr to a
> struct msi_domain_info.
> 
> It seems that a number of other pci host drivers do the same, so I am
> surprised that no one else has seen this.

Can you please give this hack a go and let me know if that helps?

Thanks,

	M.

Comments

Phil Edworthy Nov. 23, 2015, 9:44 a.m. UTC | #1
Hi Marc,

On 20 November 2015 09:49, Marc Zyngier wrote:
> On 18/11/15 18:01, Phil Edworthy wrote:
> > Hi Marc,
> >
> > On 16 November 2015 18:31, Marc Zyngier wrote:
> >> On 13/11/15 09:36, Phil Edworthy wrote:
> > <snip>
> >>> Since the stack trace doesn't help that much I added some tracing:
> >>> pci_msi_setup_msi_irqs()
> >>>   calls pci_msi_get_domain()
> >>>     calls dev_get_msi_domain(), gets a non-NULL domain.
> >>> pci_msi_setup_msi_irqs()
> >>>   calls pci_msi_domain_alloc_irqs()
> >>>     calls msi_domain_alloc_irqs()
> >>> msi_domain_alloc_irqs:273: ops=ffffffc03193a810
> >>> msi_domain_alloc_irqs:274: ops->msi_check=ffffffc031161418
> >>> systemd-udevd[1311]: undefined instruction: pc=ffffffc03116141c
> >>> That looks to me as though msi_check is off pointing to the weeds.
> >>
> >> So the next step is to find out who initializes msi_check. Assuming
> >> someone does...
> > Nothing initializes msi_check...
> >
> >
> >>> By passing a NULL domain into irq_domain_add_linear() you get:
> >>> pci_msi_setup_msi_irqs()
> >>>   calls pci_msi_get_domain()
> >>>     calls dev_get_msi_domain(), gets a NULL domain.
> >>>     calls arch_setup_msi_irq()
> >>> All ok then.
> >>
> >> Yes, because you're sidestepping the issue. Any chance you could dig a
> >> bit deeper? I'd really like to nail this one down (before we convert
> >> your PCI driver to the right API... ;-).
> > The problem appears to be that when the pci host driver enables msi
> > it calls the following:
> > 	msi->domain = irq_domain_add_linear(pcie->dev->of_node,
> INT_PCI_MSI_NR,
> > 					    &msi_domain_ops, &msi->chip);
> > The last arg is documented as:
> > * @host_data: Controller private data pointer
> > In _irq_domain_add() this ptr is stored in struct irq_domain's host_data.
> >
> > However, msi_domain_alloc_irqs() expects host_data to be a ptr to a
> > struct msi_domain_info.
> >
> > It seems that a number of other pci host drivers do the same, so I am
> > surprised that no one else has seen this.
> 
> Can you please give this hack a go and let me know if that helps?
Works for me!

Many thanks
Phil

> diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
> index 53e4632..7eaa4c8 100644
> --- a/drivers/pci/msi.c
> +++ b/drivers/pci/msi.c
> @@ -54,7 +54,7 @@ static int pci_msi_setup_msi_irqs(struct pci_dev *dev, int
> nvec, int type)
>  	struct irq_domain *domain;
> 
>  	domain = pci_msi_get_domain(dev);
> -	if (domain)
> +	if (domain && irq_domain_is_hierarchy(domain))
>  		return pci_msi_domain_alloc_irqs(domain, dev, nvec, type);
> 
>  	return arch_setup_msi_irqs(dev, nvec, type);
> @@ -65,7 +65,7 @@ static void pci_msi_teardown_msi_irqs(struct pci_dev *dev)
>  	struct irq_domain *domain;
> 
>  	domain = pci_msi_get_domain(dev);
> -	if (domain)
> +	if (domain && irq_domain_is_hierarchy(domain))
>  		pci_msi_domain_free_irqs(domain, dev);
>  	else
>  		arch_teardown_msi_irqs(dev);
> 
> --
> Jazz is not dead. It just smells funny...
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Marc Zyngier Nov. 23, 2015, 10:15 a.m. UTC | #2
On Mon, 23 Nov 2015 09:44:10 +0000
Phil Edworthy <phil.edworthy@renesas.com> wrote:

> Hi Marc,
> 
> On 20 November 2015 09:49, Marc Zyngier wrote:
> > On 18/11/15 18:01, Phil Edworthy wrote:
> > > Hi Marc,
> > >
> > > On 16 November 2015 18:31, Marc Zyngier wrote:
> > >> On 13/11/15 09:36, Phil Edworthy wrote:
> > > <snip>
> > >>> Since the stack trace doesn't help that much I added some tracing:
> > >>> pci_msi_setup_msi_irqs()
> > >>>   calls pci_msi_get_domain()
> > >>>     calls dev_get_msi_domain(), gets a non-NULL domain.
> > >>> pci_msi_setup_msi_irqs()
> > >>>   calls pci_msi_domain_alloc_irqs()
> > >>>     calls msi_domain_alloc_irqs()
> > >>> msi_domain_alloc_irqs:273: ops=ffffffc03193a810
> > >>> msi_domain_alloc_irqs:274: ops->msi_check=ffffffc031161418
> > >>> systemd-udevd[1311]: undefined instruction: pc=ffffffc03116141c
> > >>> That looks to me as though msi_check is off pointing to the weeds.
> > >>
> > >> So the next step is to find out who initializes msi_check. Assuming
> > >> someone does...
> > > Nothing initializes msi_check...
> > >
> > >
> > >>> By passing a NULL domain into irq_domain_add_linear() you get:
> > >>> pci_msi_setup_msi_irqs()
> > >>>   calls pci_msi_get_domain()
> > >>>     calls dev_get_msi_domain(), gets a NULL domain.
> > >>>     calls arch_setup_msi_irq()
> > >>> All ok then.
> > >>
> > >> Yes, because you're sidestepping the issue. Any chance you could dig a
> > >> bit deeper? I'd really like to nail this one down (before we convert
> > >> your PCI driver to the right API... ;-).
> > > The problem appears to be that when the pci host driver enables msi
> > > it calls the following:
> > > 	msi->domain = irq_domain_add_linear(pcie->dev->of_node,
> > INT_PCI_MSI_NR,
> > > 					    &msi_domain_ops, &msi->chip);
> > > The last arg is documented as:
> > > * @host_data: Controller private data pointer
> > > In _irq_domain_add() this ptr is stored in struct irq_domain's host_data.
> > >
> > > However, msi_domain_alloc_irqs() expects host_data to be a ptr to a
> > > struct msi_domain_info.
> > >
> > > It seems that a number of other pci host drivers do the same, so I am
> > > surprised that no one else has seen this.
> > 
> > Can you please give this hack a go and let me know if that helps?
> Works for me!

Cool. I'll post a patch with your Reported-by/Tested-by later today.

Thanks a lot.

	M.
Wolfram Sang Nov. 23, 2015, 10:29 a.m. UTC | #3
Hi Marc,

> > > Can you please give this hack a go and let me know if that helps?
> > Works for me!
> 
> Cool. I'll post a patch with your Reported-by/Tested-by later today.

Please put me on CC as well.

Thanks,

   Wolfram
diff mbox

Patch

diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index 53e4632..7eaa4c8 100644
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -54,7 +54,7 @@  static int pci_msi_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
 	struct irq_domain *domain;
 
 	domain = pci_msi_get_domain(dev);
-	if (domain)
+	if (domain && irq_domain_is_hierarchy(domain))
 		return pci_msi_domain_alloc_irqs(domain, dev, nvec, type);
 
 	return arch_setup_msi_irqs(dev, nvec, type);
@@ -65,7 +65,7 @@  static void pci_msi_teardown_msi_irqs(struct pci_dev *dev)
 	struct irq_domain *domain;
 
 	domain = pci_msi_get_domain(dev);
-	if (domain)
+	if (domain && irq_domain_is_hierarchy(domain))
 		pci_msi_domain_free_irqs(domain, dev);
 	else
 		arch_teardown_msi_irqs(dev);