diff --git a/coregrind/m_syswrap/syswrap-linux.c b/coregrind/m_syswrap/syswrap-linux.c
index f83b59f..20b6d0e 100644
--- a/coregrind/m_syswrap/syswrap-linux.c
+++ b/coregrind/m_syswrap/syswrap-linux.c
@@ -5373,6 +5373,8 @@
 {
    *flags |= SfMayBlock;
 
+   ARG2 = (UInt)ARG2;
+
    // We first handle the ones that don't use ARG3 (even as a
    // scalar/non-pointer argument).
    switch (ARG2 /* request */) {
@@ -7103,6 +7105,8 @@
 {
    vg_assert(SUCCESS);
 
+   ARG2 = (UInt)ARG2;
+
    /* --- BEGIN special IOCTL handlers for specific Android hardware --- */
 
 #  if defined(VGPV_arm_linux_android) || defined(VGPV_x86_linux_android) \