[PULL,02/43] hw/intc/arm_gic: Fix writes to GICD_ITARGETSRn

Commit Message

Peter Maydell May 31, 2024, 12:03 p.m. UTC

From: Sebastian Huber <[e-mail]>

According to the GICv2 specification section 4.3.12, "Interrupt Processor
Targets Registers, GICD_ITARGETSRn":

"Any change to a CPU targets field value:
[...]
* Has an effect on any pending interrupts. This means:
  - adding a CPU interface to the target list of a pending interrupt makes that
    interrupt pending on that CPU interface
  - removing a CPU interface from the target list of a pending interrupt
    removes the pending state of that interrupt on that CPU interface."

Signed-off-by: Sebastian Huber <[e-mail]>
Message-id: [e-mail]
Reviewed-by: Peter Maydell <[e-mail]>
Signed-off-by: Peter Maydell <[e-mail]>
---
 hw/intc/arm_gic.c | 7 +++++++
 1 file changed, 7 insertions(+)

Patch

diff --git a/hw/intc/arm_gic.c b/hw/intc/arm_gic.c
index 04e5a11660c..806832439b4 100644
--- a/hw/intc/arm_gic.c
+++ b/hw/intc/arm_gic.c
@@ -1410,6 +1410,13 @@  static void gic_dist_writeb(void *opaque, hwaddr offset,
                 value = ALL_CPU_MASK;
             }
             s->irq_target[irq] = value & ALL_CPU_MASK;
+            if (irq >= GIC_INTERNAL && s->irq_state[irq].pending) {
+                /*
+                 * Changing the target of an interrupt that is currently
+                 * pending updates the set of CPUs it is pending on.
+                 */
+                s->irq_state[irq].pending = value & ALL_CPU_MASK;
+            }
         }
     } else if (offset < 0xf00) {
         /* Interrupt Configuration.  */