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. Yup, me too. Feels like a massive blunder. I'll cook something. Thanks a lot for tracking this. M. -- Jazz is not dead. It just smells funny... -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
