diff --git a/arch/ia64/hp/sim/boot/fw-emu.c b/arch/ia64/hp/sim/boot/fw-emu.c
index 1189d035d31..bf6d9d8c802 100644
--- a/arch/ia64/hp/sim/boot/fw-emu.c
+++ b/arch/ia64/hp/sim/boot/fw-emu.c
@@ -285,7 +285,7 @@ sys_fw_init (const char *args, int arglen)
 	}
 	cmd_line[arglen] = '\0';
 
-	memset(efi_systab, 0, sizeof(efi_systab));
+	memset(efi_systab, 0, sizeof(*efi_systab));
 	efi_systab->hdr.signature = EFI_SYSTEM_TABLE_SIGNATURE;
 	efi_systab->hdr.revision  = ((1 << 16) | 00);
 	efi_systab->hdr.headersize = sizeof(efi_systab->hdr);