On 28/01/15 15:43, Bjorn Helgaas wrote: > On Wed, Jan 28, 2015 at 9:27 AM, Marc Zyngier <marc.zyngier@xxxxxxx> wrote: >> Hi Gerry, >> >> On 28/01/15 15:21, Jiang Liu wrote: >>> >>> >>> On 2015/1/28 22:51, Marc Zyngier wrote: >>>> pcibios_update_irq writes an irq number into the config space >>>> of a given PCI device, but ignores the fact that this number >>>> is a virtual interrupt number, which might be a very different >>>> value from what the underlying hardware is using. >>>> >>>> The obvious fix is to fetch the HW interrupt number from the >>>> corresponding irq_data structure. This is slightly complicated >>>> by the fact that this interrupt might be services by a stacked >>>> domain. >>>> >>>> This has been tested on KVM with kvmtool. >>>> >>>> Reported-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx> >>>> Tested-by: Andre Przywara <andre.przywara@xxxxxxx> >>>> Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx> >>>> --- >>>> drivers/pci/setup-irq.c | 12 ++++++++++-- >>>> 1 file changed, 10 insertions(+), 2 deletions(-) >>>> >>>> diff --git a/drivers/pci/setup-irq.c b/drivers/pci/setup-irq.c >>>> index 4e2d595..828cbc9 100644 >>>> --- a/drivers/pci/setup-irq.c >>>> +++ b/drivers/pci/setup-irq.c >>>> @@ -15,11 +15,19 @@ >>>> #include <linux/errno.h> >>>> #include <linux/ioport.h> >>>> #include <linux/cache.h> >>>> +#include <linux/irq.h> >>>> >>>> void __weak pcibios_update_irq(struct pci_dev *dev, int irq) >>>> { >>>> - dev_dbg(&dev->dev, "assigning IRQ %02d\n", irq); >>>> - pci_write_config_byte(dev, PCI_INTERRUPT_LINE, irq); >>>> + struct irq_data *d; >>>> + >>>> + d = irq_get_irq_data(irq); >>>> +#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY >>>> + while (d->parent_data) >>>> + d = d->parent_data; >>>> +#endif >>>> + dev_dbg(&dev->dev, "assigning IRQ %02ld\n", d->hwirq); >>>> + pci_write_config_byte(dev, PCI_INTERRUPT_LINE, d->hwirq); >>>> } >>> Hi Mark, >>> Instead of modifying the common version, how about >>> implementing an arch specific version? Arch may have different >>> way to determine the irq number. Above implementation doesn't >>> work with x86, for example. >> >> If you look at the Makefile, this file is used on: >> >> obj-$(CONFIG_ALPHA) += setup-irq.o >> obj-$(CONFIG_ARM) += setup-irq.o >> obj-$(CONFIG_UNICORE32) += setup-irq.o >> obj-$(CONFIG_SUPERH) += setup-irq.o >> obj-$(CONFIG_MIPS) += setup-irq.o >> obj-$(CONFIG_TILE) += setup-irq.o >> obj-$(CONFIG_SPARC_LEON) += setup-irq.o >> obj-$(CONFIG_M68K) += setup-irq.o >> >> x86 doesn't use that at all. > > Since you're looking at this, Marc, do you see a nice way to get rid > of these arch dependencies in the Makefile and unify this a bit? We > still have this pci_fixup_irqs() ugliness -- it's not really > arch-specific at all, but it's called from arch code, and it uses > for_each_pci_dev(), which obviously only works for things present at > boot and not for things hot-added later. I can have a look at this in the next cycle - I'm a bit strapped for time just now. As for for_each_pci_dev(), I'm not completely clear about what it should be replaced for. Do we have some form of notifier for this? Thanks, 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