x86, ACPI, irq: Fix possible eror in GSI to IRQ mapping for legacy IRQ

A default identity mapping between GSI and IRQ is built for legacy IRQs.
So when overriding the default identity mapping for legacy IRQs,
we should also invalidate isa_irq_to_gsi[gsi] when setting
isa_irq_to_gsi[irq] = gsi.  Otherwise there may be two entries with the
same GSI in the isa_irq_to_gsi array, and acpi_isa_irq_to_gsi() may give
wrong result.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Len Brown <len.brown@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Link: http://lkml.kernel.org/r/1402302011-23642-10-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Jiang Liu 2014-06-09 16:19:38 +08:00 committed by Thomas Gleixner
parent 2c0a6894df
commit 2e0ad0e2c1

View File

@ -366,6 +366,13 @@ static void __init mp_override_legacy_irq(u8 bus_irq, u8 polarity, u8 trigger,
mp_save_irq(&mp_irq);
/*
* Reset default identity mapping if gsi is also an legacy IRQ,
* otherwise there will be more than one entry with the same GSI
* and acpi_isa_irq_to_gsi() may give wrong result.
*/
if (gsi < NR_IRQS_LEGACY && isa_irq_to_gsi[gsi] == gsi)
isa_irq_to_gsi[gsi] = ACPI_INVALID_GSI;
isa_irq_to_gsi[bus_irq] = gsi;
}
@ -621,7 +628,8 @@ EXPORT_SYMBOL_GPL(acpi_gsi_to_irq);
int acpi_isa_irq_to_gsi(unsigned isa_irq, u32 *gsi)
{
if (isa_irq < NR_IRQS_LEGACY) {
if (isa_irq < NR_IRQS_LEGACY &&
isa_irq_to_gsi[isa_irq] != ACPI_INVALID_GSI) {
*gsi = isa_irq_to_gsi[isa_irq];
return 0;
}