Commit 990785dc authored Jan 22, 2015 by Bryan O'Donoghue Committed by Greg Kroah-Hartman Jan 29, 2015

x86/apic: Re-enable PCI_MSI support for non-SMP X86_32



commit 38a1dfda8e77d7ba74c94d06d8bc41ba98a4bc8c upstream.

Commit 0dbc6078 ('x86, build, pci: Fix PCI_MSI build on !SMP')
introduced the dependency that X86_UP_APIC is only available when
PCI_MSI is false. This effectively prevents PCI_MSI support on 32bit
UP systems because it disables both APIC and IO-APIC. But APIC support
is architecturally required for PCI_MSI.

The intention of the patch was to enforce APIC support when PCI_MSI is
enabled, but failed to do so.

Remove the !PCI_MSI dependency from X86_UP_APIC and enforce
X86_UP_APIC when PCI_MSI support is enabled on 32bit UP systems.

[ tglx: Massaged changelog ]

Fixes 0dbc6078 'x86, build, pci: Fix PCI_MSI build on !SMP'
Signed-off-by: Bryan O'Donoghue <pure.logic@nexus-software.ie>
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Link: http://lkml.kernel.org/r/1421967529-9037-1-git-send-email-pure.logic@nexus-software.ie


Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 7b6b3d67

arch/x86/Kconfig

+5 −1

Original line number	Original line	Diff line number	Diff line
	@@ -856,7 +856,7 @@ source "kernel/Kconfig.preempt"

	config X86_UP_APIC		config X86_UP_APIC
	bool "Local APIC support on uniprocessors"		bool "Local APIC support on uniprocessors"
	depends on X86_32 && !SMP && !X86_32_NON_STANDARD && !PCI_MSI		depends on X86_32 && !SMP && !X86_32_NON_STANDARD
	---help---		---help---
	A local APIC (Advanced Programmable Interrupt Controller) is an		A local APIC (Advanced Programmable Interrupt Controller) is an
	integrated interrupt controller in the CPU. If you have a single-CPU		integrated interrupt controller in the CPU. If you have a single-CPU
	@@ -867,6 +867,10 @@ config X86_UP_APIC
	performance counters), and the NMI watchdog which detects hard		performance counters), and the NMI watchdog which detects hard
	lockups.		lockups.

			config X86_UP_APIC_MSI
			def_bool y
			select X86_UP_APIC if X86_32 && !SMP && !X86_32_NON_STANDARD && PCI_MSI

	config X86_UP_IOAPIC		config X86_UP_IOAPIC
	bool "IO-APIC support on uniprocessors"		bool "IO-APIC support on uniprocessors"
	depends on X86_UP_APIC		depends on X86_UP_APIC