diff --git a/hw/intc/spapr_xive_kvm.c b/hw/intc/spapr_xive_kvm.c
index 5789062379..7a86197fc9 100644
--- a/hw/intc/spapr_xive_kvm.c
+++ b/hw/intc/spapr_xive_kvm.c
@@ -720,7 +720,7 @@ int kvmppc_xive_connect(SpaprInterruptController *intc, uint32_t nr_servers,
 {
     SpaprXive *xive = SPAPR_XIVE(intc);
     XiveSource *xsrc = &xive->source;
-    size_t esb_len = xive_source_esb_len(xsrc);
+    uint64_t esb_len = xive_source_esb_len(xsrc);
     size_t tima_len = 4ull << TM_SHIFT;
     CPUState *cs;
     int fd;
@@ -824,7 +824,7 @@ void kvmppc_xive_disconnect(SpaprInterruptController *intc)
 {
     SpaprXive *xive = SPAPR_XIVE(intc);
     XiveSource *xsrc;
-    size_t esb_len;
+    uint64_t esb_len;
 
     assert(xive->fd != -1);
 
diff --git a/hw/intc/xive.c b/hw/intc/xive.c
index 5a02dd8e02..b600546e78 100644
--- a/hw/intc/xive.c
+++ b/hw/intc/xive.c
@@ -1242,7 +1242,7 @@ static void xive_source_reset(void *dev)
 static void xive_source_realize(DeviceState *dev, Error **errp)
 {
     XiveSource *xsrc = XIVE_SOURCE(dev);
-    size_t esb_len = xive_source_esb_len(xsrc);
+    uint64_t esb_len = xive_source_esb_len(xsrc);
 
     assert(xsrc->xive);
 
diff --git a/include/hw/ppc/xive.h b/include/hw/ppc/xive.h
index 28c181faa2..3a65c2f29a 100644
--- a/include/hw/ppc/xive.h
+++ b/include/hw/ppc/xive.h
@@ -218,7 +218,7 @@ static inline bool xive_source_esb_has_2page(XiveSource *xsrc)
         xsrc->esb_shift == XIVE_ESB_4K_2PAGE;
 }
 
-static inline size_t xive_source_esb_len(XiveSource *xsrc)
+static inline uint64_t xive_source_esb_len(XiveSource *xsrc)
 {
     return (1ull << xsrc->esb_shift) * xsrc->nr_irqs;
 }