Intel MID platforms has no legacy interrupts, so no IRQ descriptors
preallocated. We need to call mp_map_gsi_to_irq() to create IRQ
descriptors for APB timers and RTC timers, otherwise it may cause
invalid memory access as:
[    0.116839] BUG: unable to handle kernel NULL pointer dereference at
0000003a
[    0.123803] IP: [<c1071c0e>] setup_irq+0xf/0x4d

Signed-off-by: Jiang Liu <[email protected]>
Tested-by: Andy Shevchenko <[email protected]>
Cc: <[email protected]> # 3.17
---
 arch/x86/kernel/apb_timer.c       |    2 --
 arch/x86/platform/intel-mid/sfi.c |    2 ++
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/apb_timer.c b/arch/x86/kernel/apb_timer.c
index 5972b108f15a..b708738d016e 100644
--- a/arch/x86/kernel/apb_timer.c
+++ b/arch/x86/kernel/apb_timer.c
@@ -185,8 +185,6 @@ static void apbt_setup_irq(struct apbt_dev *adev)
 
        irq_modify_status(adev->irq, 0, IRQ_MOVE_PCNTXT);
        irq_set_affinity(adev->irq, cpumask_of(adev->cpu));
-       /* APB timer irqs are set up as mp_irqs, timer is edge type */
-       __irq_set_handler(adev->irq, handle_edge_irq, 0, "edge");
 }
 
 /* Should be called with per cpu */
diff --git a/arch/x86/platform/intel-mid/sfi.c 
b/arch/x86/platform/intel-mid/sfi.c
index 3c53a90fdb18..c14ad34776c4 100644
--- a/arch/x86/platform/intel-mid/sfi.c
+++ b/arch/x86/platform/intel-mid/sfi.c
@@ -106,6 +106,7 @@ int __init sfi_parse_mtmr(struct sfi_table_header *table)
                        mp_irq.dstapic = MP_APIC_ALL;
                        mp_irq.dstirq = pentry->irq;
                        mp_save_irq(&mp_irq);
+                       mp_map_gsi_to_irq(pentry->irq, IOAPIC_MAP_ALLOC);
        }
 
        return 0;
@@ -176,6 +177,7 @@ int __init sfi_parse_mrtc(struct sfi_table_header *table)
                mp_irq.dstapic = MP_APIC_ALL;
                mp_irq.dstirq = pentry->irq;
                mp_save_irq(&mp_irq);
+               mp_map_gsi_to_irq(pentry->irq, IOAPIC_MAP_ALLOC);
        }
        return 0;
 }
-- 
1.7.10.4

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