spapr, xics, xive: Better use of assert()s on irq claim/free paths

The irq claim and free paths for both XICS and XIVE check for some
validity conditions.  Some of these represent genuine runtime failures,
however others - particularly checking that the basic irq number is in a
sane range - could only fail in the case of bugs in the callin code.
Therefore use assert()s instead of runtime failures for those.

In addition the non backend-specific part of the claim/free paths should
only be used for PAPR external irqs, that is in the range SPAPR_XIRQ_BASE
to the maximum irq number.  Put assert()s for that into the top level
dispatchers as well.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>

1 files changed, 2 insertions, 6 deletions

diff --git a/hw/intc/spapr_xive.c b/hw/intc/spapr_xive.c
index c1c97192a7..47b5ec0b56 100644
--- a/hw/intc/spapr_xive.c
+++ b/hw/intc/spapr_xive.c
@@ -532,9 +532,7 @@ bool spapr_xive_irq_claim(SpaprXive *xive, uint32_t lisn, bool lsi)
 {
     XiveSource *xsrc = &xive->source;
 
-    if (lisn >= xive->nr_irqs) {
-        return false;
-    }
+    assert(lisn < xive->nr_irqs);
 
     /*
      * Set default values when allocating an IRQ number
@@ -559,9 +557,7 @@ bool spapr_xive_irq_claim(SpaprXive *xive, uint32_t lisn, bool lsi)
 
 bool spapr_xive_irq_free(SpaprXive *xive, uint32_t lisn)
 {
-    if (lisn >= xive->nr_irqs) {
-        return false;
-    }
+    assert(lisn < xive->nr_irqs);
 
     xive->eat[lisn].w &= cpu_to_be64(~EAS_VALID);
     return true;