From 0bad2a8a903b289300f2e552ce1c72b29ce20107 Mon Sep 17 00:00:00 2001
From: Peter Kooiman <pkooiman@users.noreply.github.com>
Date: Mon, 26 Oct 2015 18:25:59 +0100
Subject: [PATCH] Added test for executing from  MIPS kseg0/ksegq1 memory
 ranges to tests/regress

---
 tests/regress/mips_kseg0_1.c | 78 ++++++++++++++++++++++++++++++++++++
 1 file changed, 78 insertions(+)
 create mode 100644 tests/regress/mips_kseg0_1.c

diff --git a/tests/regress/mips_kseg0_1.c b/tests/regress/mips_kseg0_1.c
new file mode 100644
index 00000000..e2ba02b1
--- /dev/null
+++ b/tests/regress/mips_kseg0_1.c
@@ -0,0 +1,78 @@
+#include <unicorn/unicorn.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+
+//Test for the MIPS kseg0 and kseg1 memory segments
+//The kseg0 address range 0x80000000-0x9FFFFFFF is not mapped through the MMU,
+//but instead is directly translated to low ram by masking off the high address bit.
+//Similarly, the address range kseg1 0xA00000000-0xBFFFFFF is translated directly to
+//low ram by masking off the top 3 address bits.
+//Qemu handles these address ranges correctly, but there are issues with the way Unicorn checks for
+//a valid memory mapping when executing code in the kseg0 or kseg1 memory range.
+//In particular, Unicorn checks for a valid mapping using the virtual address when executing from kseg0/1, 
+//when it should probably use the real address in low ram.
+
+#define KSEG0_VIRT_ADDRESS 0x80001000 //Virtual address in kseg0, mapped by processor (and QEMU) to 0x1000
+#define KSEG1_VIRT_ADDRESS 0xA0001000 //Virtual address in kseg1, mapped by processor (and QEMU) to 0x1000
+#define KSEG0_1_REAL_ADDRESS 0x1000 //Real address corresponding to the above addresses in kseg0/1
+
+#define MIPS_CODE_EL "\x56\x34\x21\x34" // ori $at, $at, 0x3456;
+
+int main() 
+{
+    
+    uc_engine *uc;
+	uc_err err;
+
+	err = uc_open(UC_ARCH_MIPS, UC_MODE_MIPS32, &uc);
+	if (err)
+	{
+		printf("uc_open %d\n", err);
+		return 1;
+	}
+
+	// map 4Kb memory for this emulation, into the real address space
+	err = uc_mem_map(uc, KSEG0_1_REAL_ADDRESS, 4 * 1024, UC_PROT_ALL);
+	if (err)
+	{
+		printf("uc_mem_map %d\n", err);
+		return 1;
+	}
+
+	// write machine code to be emulated to memory
+	err = uc_mem_write(uc, KSEG0_1_REAL_ADDRESS, MIPS_CODE_EL, sizeof(MIPS_CODE_EL) - 1);
+	if (err)
+	{
+		printf("uc_mem_map %d\n", err);
+		return 1;
+	}
+
+    //Start emulation at real address, this currently succeeds
+	err = uc_emu_start(uc, KSEG0_1_REAL_ADDRESS, KSEG0_1_REAL_ADDRESS + 4, 0, 0);
+	if (err)
+	{
+		printf("uc_emu_start at real address: %d\n", err);
+		return 1;
+	}
+
+	//Start emulation at virtual address in kseg0, this cuurently fails
+	err = uc_emu_start(uc, KSEG0_VIRT_ADDRESS, KSEG0_VIRT_ADDRESS + 4, 0, 0);
+	if (err)
+	{
+		printf("uc_emu_start at kseg0 address: %d\n", err);
+		return 1;
+	}
+
+	//Start emulation at virtual address in kseg1, this currently fails
+	err = uc_emu_start(uc, KSEG1_VIRT_ADDRESS, KSEG1_VIRT_ADDRESS + 4, 0, 0);
+	if (err)
+	{
+		printf("uc_emu_start at kseg1 address: %d\n", err);
+		return 1;
+	}
+
+	uc_close(uc);
+    
+    return 0;
+}