x86, pci: introduce pci=ioapicreroute kernel cmdline option

Introduce pci=ioapicreroute kernel cmdline option to enable rerouting of boot
interrupts to the primary io-apic.

Signed-off-by: Stefan Assmann <sassmann@suse.de>
Signed-off-by: Olaf Dabrunz <od@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 4 insertions, 0 deletions

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 1aebe9dffbaa..df262b3c3d6e 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1521,6 +1521,10 @@ and is between 256 and 4096 characters. It is defined in the file
                 noioapicquirk   [APIC] Disable all boot interrupt quirks.
                                 Safety option to keep boot IRQs enabled. This
                                 should never be necessary.
+                ioapicreroute   [APIC] Enable rerouting of boot IRQs to the
+                                primary IO-APIC for bridges that cannot disable
+                                boot IRQs. This fixes a source of spurious IRQs
+                                when the system masks IRQs.
                 biosirq         [X86-32] Use PCI BIOS calls to get the interrupt
                                 routing table. These calls are known to be buggy
                                 on several machines and they hang the machine