diff --git a/drivers/char/ipmi/ipmi_si_mem_io.c b/drivers/char/ipmi/ipmi_si_mem_io.c
index 638f4ab88f445a51840a73203f739946873941e0..75583612ab10551367cd74d727a0cbda958d0429 100644
--- a/drivers/char/ipmi/ipmi_si_mem_io.c
+++ b/drivers/char/ipmi/ipmi_si_mem_io.c
@@ -51,7 +51,7 @@ static unsigned char mem_inq(const struct si_sm_io *io, unsigned int offset)
 static void mem_outq(const struct si_sm_io *io, unsigned int offset,
 		     unsigned char b)
 {
-	writeq(b << io->regshift, (io->addr)+(offset * io->regspacing));
+	writeq((u64)b << io->regshift, (io->addr)+(offset * io->regspacing));
 }
 #endif