The MemoryRegionOps gicv3_its_translation_ops currently provides only
a .write_with_attrs function, because the only register in this
region is the write-only GITS_TRANSLATER. However, if you don't
provide a read function and the guest tries reading from this memory
region, QEMU will crash because
memory_region_read_with_attrs_accessor() calls a NULL pointer.
Add a read function which always returns 0, to cover both bogus
attempts to read GITS_TRANSLATER and also reads from the rest of the
region, which is documented to be reserved, RES0.
Signed-off-by: Peter Maydell <peter.mayd...@linaro.org>
---
hw/intc/arm_gicv3_its.c | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/hw/intc/arm_gicv3_its.c b/hw/intc/arm_gicv3_its.c
index d9ff7b88492..b17f2631269 100644
--- a/hw/intc/arm_gicv3_its.c
+++ b/hw/intc/arm_gicv3_its.c
@@ -813,6 +813,18 @@ static void extract_cmdq_params(GICv3ITSState *s)
}
}
+static MemTxResult gicv3_its_translation_read(void *opaque, hwaddr offset,
+ uint64_t *data, unsigned size,
+ MemTxAttrs attrs)
+{
+ /*
+ * GITS_TRANSLATER is write-only, and all other addresses
+ * in the interrupt translation space frame are RES0.
+ */
+ *data = 0;
+ return MEMTX_OK;
+}
+
static MemTxResult gicv3_its_translation_write(void *opaque, hwaddr offset,
uint64_t data, unsigned size,
MemTxAttrs attrs)
@@ -1168,6 +1180,7 @@ static const MemoryRegionOps gicv3_its_control_ops = {
};
static const MemoryRegionOps gicv3_its_translation_ops = {
+ .read_with_attrs = gicv3_its_translation_read,
.write_with_attrs = gicv3_its_translation_write,
.valid.min_access_size = 2,
.valid.max_access_size = 4,
--
2.25.1
