A bug in the KVM GIC init code set the priority mask to the
highest possible value, while the reset value should be zero.

Now that the kernel bug is fixed, kvm-tool must properly configure
its GIC CPU interface in order to receive the boot IPI.  Just set
the GICC_PMR register to the maximum value (0xff), and it "just works".

Cc: Will Deacon <will.dea...@arm.com>
Cc: Pekka Enberg <penb...@kernel.org>
Signed-off-by: Marc Zyngier <marc.zyng...@arm.com>
---
v2: Changed the constant name to GIC_CPUI_PMR_MIN_PRIO, as suggested by
    Peter Maydell

 tools/kvm/arm/aarch32/smp-pen.S        | 4 ++++
 tools/kvm/arm/include/arm-common/gic.h | 2 ++
 2 files changed, 6 insertions(+)

diff --git a/tools/kvm/arm/aarch32/smp-pen.S b/tools/kvm/arm/aarch32/smp-pen.S
index 0861171..2398297 100644
--- a/tools/kvm/arm/aarch32/smp-pen.S
+++ b/tools/kvm/arm/aarch32/smp-pen.S
@@ -17,6 +17,10 @@ smp_pen_start:
        mov     r1, #GIC_CPUI_CTLR_EN
        str     r1, [r0]
 
+       @ Set the priority mask to accept any interrupt
+       mov     r1, #GIC_CPUI_PMR_MIN_PRIO
+       str     r1, [r0, #4]
+
        @ Now wait for the primary to poke us
        adr     r0, smp_jump_addr
        ldr     r1, =AARCH32_SMP_BAD_MAGIC
diff --git a/tools/kvm/arm/include/arm-common/gic.h 
b/tools/kvm/arm/include/arm-common/gic.h
index d534174..20dc691 100644
--- a/tools/kvm/arm/include/arm-common/gic.h
+++ b/tools/kvm/arm/include/arm-common/gic.h
@@ -20,6 +20,8 @@
 
 #define GIC_CPUI_CTLR_EN               (1 << 0)
 
+#define GIC_CPUI_PMR_MIN_PRIO          0xff
+
 #define GIC_MAX_CPUS                   8
 #define GIC_MAX_IRQ                    255
 
-- 
1.8.0.1


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