[PATCH] x86, mrst: use a temporary variable for SFI irq

Mika Westerberg
2011-09-14T07:56:15Z

SFI tables reside in RAM and should not be modified once they are written.
Current code went to set pentry->irq to zero which causes subsequent reads
to fail with invalid SFI table checksum.

To fix this we use temporary variable for irq number.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: stable@kernel.org
---
arch/x86/platform/mrst/mrst.c | 22 ++++++++++++----------
1 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/arch/x86/platform/mrst/mrst.c b/arch/x86/platform/mrst/mrst.c
index 58425ad..fe73276 100644
--- a/arch/x86/platform/mrst/mrst.c
+++ b/arch/x86/platform/mrst/mrst.c
@@ -678,38 +678,40 @@ static int __init sfi_parse_devs(struct sfi_table_header *table)
pentry = (struct sfi_device_table_entry *)sb->pentry;

for (i = 0; i < num; i++, pentry++) {
- if (pentry->irq != (u8)0xff) { /* native RTE case */
+ int irq = pentry->irq;
+
+ if (irq != (u8)0xff) { /* native RTE case */
/* these SPI2 devices are not exposed to system as PCI
* devices, but they have separate RTE entry in IOAPIC
* so we have to enable them one by one here
*/
- ioapic = mp_find_ioapic(pentry->irq);
+ ioapic = mp_find_ioapic(irq);
irq_attr.ioapic = ioapic;
- irq_attr.ioapic_pin = pentry->irq;
+ irq_attr.ioapic_pin = irq;
irq_attr.trigger = 1;
irq_attr.polarity = 1;
- io_apic_set_pci_routing(NULL, pentry->irq, &irq_attr);
+ io_apic_set_pci_routing(NULL, irq, &irq_attr);
} else
- pentry->irq = 0; /* No irq */
+ irq = 0; /* No irq */

switch (pentry->type) {
case SFI_DEV_TYPE_IPC:
/* ID as IRQ is a hack that will go away */
- pdev = platform_device_alloc(pentry->name, pentry->irq);
+ pdev = platform_device_alloc(pentry->name, irq);
if (pdev == NULL) {
pr_err("out of memory for SFI platform device '%s'.\n",
pentry->name);
continue;
}
- install_irq_resource(pdev, pentry->irq);
+ install_irq_resource(pdev, irq);
pr_debug("info[%2d]: IPC bus, name = %16.16s, "
- "irq = 0x%2x\n", i, pentry->name, pentry->irq);
+ "irq = 0x%2x\n", i, pentry->name, irq);
sfi_handle_ipc_dev(pdev);
break;
case SFI_DEV_TYPE_SPI:
memset(&spi_info, 0, sizeof(spi_info));
strncpy(spi_info.modalias, pentry->name, SFI_NAME_LEN);
- spi_info.irq = pentry->irq;
+ spi_info.irq = irq;
spi_info.bus_num = pentry->host_num;
spi_info.chip_select = pentry->addr;
spi_info.max_speed_hz = pentry->max_freq;
@@ -726,7 +728,7 @@ static int __init sfi_parse_devs(struct sfi_table_header *table)
memset(&i2c_info, 0, sizeof(i2c_info));
bus = pentry->host_num;
strncpy(i2c_info.type, pentry->name, SFI_NAME_LEN);
- i2c_info.irq = pentry->irq;
+ i2c_info.irq = irq;
i2c_info.addr = pentry->addr;
pr_debug("info[%2d]: I2C bus = %d, name = %16.16s, "
"irq = 0x%2x, addr = 0x%x\n", i, bus,
--
1.7.5.4