[+cc Konrad] On Thu, Oct 3, 2013 at 3:59 AM, Thomas Petazzoni <[email protected]> wrote: > Commit ebd97be635 ('PCI: remove ARCH_SUPPORTS_MSI kconfig option') > removed the ARCH_SUPPORTS_MSI option which architectures could select > to indicate that they support MSI. Now, all architectures are supposed > to build fine when MSI support is enabled: instead of having the > architecture tell *when* MSI support can be used, it's up to the > architecture code to ensure that MSI support can be enabled. > > On x86, commit ebd97be635 removed the following line: > > select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC) > > Which meant that MSI support was only available when the local APIC > and I/O APIC were enabled. While this is always true on SMP or x86-64, > it is not necessarily the case on i386 !SMP. > > The below patch makes sure that the local APIC and I/O APIC support is > always enabled when MSI support is enabled. To do so, it: > > * Ensures the X86_UP_APIC option is not visible when PCI_MSI is > enabled. This is the option that allows, on UP machines, to enable > or not the APIC support. It is already not visible on SMP systems, > or x86-64 systems, for example. We're simply also making it > invisible on i386 MSI systems. > > * Ensures that the X86_LOCAL_APIC and X86_IO_APIC options are 'y' > when PCI_MSI is enabled. > > Notice that this change requires a change in drivers/iommu/Kconfig to > avoid a recursive Kconfig dependencey. The AMD_IOMMU option selects > PCI_MSI, but was depending on X86_IO_APIC. This dependency is no > longer needed: as soon as PCI_MSI is selected, the presence of > X86_IO_APIC is guaranteed. Moreover, the AMD_IOMMU already depended on > X86_64, which already guaranteed that X86_IO_APIC was enabled, so this > dependency was anyway redundant. > > Signed-off-by: Thomas Petazzoni <[email protected]> > Reported-by: Konrad Rzeszutek Wilk <[email protected]> > Cc: [email protected] > Cc: [email protected] > Cc: [email protected] > Cc: [email protected] > Cc: [email protected] > Cc: [email protected] > Cc: [email protected]
FWIW, Acked-by: Bjorn Helgaas <[email protected]> x86 maintainers, I assume you'll pick this up. Let me know if you want me to do it. Bjorn -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
