Copy BAT hook to the end of our memory area

src/kernel.cpp

@@ -1,9 +1,15 @@
 #include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+#include <coreinit/cache.h>
+
 #include "kernel.h"
 
 /* assembly functions */
 extern "C" void Syscall_0x36(void);
 extern "C" void KernelPatches(void);
+extern "C" void KernelPatchesFinal(void);
+extern "C" void SaveAndResetDataBATs_And_SRs_hook(void);
 
 void __attribute__ ((noinline)) kern_write(void *addr, uint32_t value);
 
@@ -17,6 +23,20 @@ void doKernelSetup(){
     Syscall_0x36();
 }
 
+void doKernelSetup2() {
+    memcpy((void*)0x00FFF000, (void*)SaveAndResetDataBATs_And_SRs_hook, 0x1000);
+    ICInvalidateRange((void*)0x00FFF000, 0x1000);
+    DCFlushRange((void*)0x00FFF000, 0x1000);
+
+    kern_write((void*)(KERN_SYSCALL_TBL_1 + (0x36 * 4)), (unsigned int)KernelPatchesFinal);
+    kern_write((void*)(KERN_SYSCALL_TBL_2 + (0x36 * 4)), (unsigned int)KernelPatchesFinal);
+    kern_write((void*)(KERN_SYSCALL_TBL_3 + (0x36 * 4)), (unsigned int)KernelPatchesFinal);
+    kern_write((void*)(KERN_SYSCALL_TBL_4 + (0x36 * 4)), (unsigned int)KernelPatchesFinal);
+    kern_write((void*)(KERN_SYSCALL_TBL_5 + (0x36 * 4)), (unsigned int)KernelPatchesFinal);
+
+    Syscall_0x36();
+}
+
 /* Write a 32-bit word with kernel permissions */
 void __attribute__ ((noinline)) kern_write(void *addr, uint32_t value) {
     asm volatile (

src/kernel.h

@@ -8,3 +8,4 @@
 
 
 void doKernelSetup();
+void doKernelSetup2();

src/kernel_asm_other.S

@@ -0,0 +1,60 @@
+#define BAT_SETUP_HOOK_ADDR         0xFFF1D624
+
+#define BAT_SETUP_HOOK_ENTRY        0x00FFF000
+
+    .globl KernelPatchesFinal
+KernelPatchesFinal:
+    # store the old DBAT0
+    mfdbatu r5, 0
+    mfdbatl r6, 0
+
+    # memory barrier
+    eieio
+    isync
+
+    # setup DBAT0 for access to kernel code memory
+    lis r3, 0xFFF0
+    ori r3, r3, 0x0002
+    mtdbatu 0, r3
+    lis r3, 0xFFF0
+    ori r3, r3, 0x0032
+    mtdbatl 0, r3
+
+    # memory barrier
+    eieio
+    isync
+
+    # SaveAndResetDataBATs_And_SRs hook setup, but could be any BAT function though
+    # just chosen because its simple
+    lis r3, BAT_SETUP_HOOK_ADDR@h
+    ori r3, r3, BAT_SETUP_HOOK_ADDR@l
+
+    lis r4, (BAT_SETUP_HOOK_ENTRY | 0x48000003)@h      #   bla BAT_SETUP_HOOK_ENTRY
+    ori r4, r4, (BAT_SETUP_HOOK_ENTRY | 0x48000003)@l
+    stw r4, 0x24(r3)
+
+    # flush and invalidate the replaced instructions
+    lis r3, (BAT_SETUP_HOOK_ADDR & ~31)@h
+    ori r3, r3, (BAT_SETUP_HOOK_ADDR & ~31)@l
+    dcbf 0, r3
+    icbi 0, r3
+    lis r3, ((BAT_SETUP_HOOK_ADDR + 0x40) & ~31)@h
+    ori r3, r3, ((BAT_SETUP_HOOK_ADDR + 0x40) & ~31)@l
+    dcbf 0, r3
+    icbi 0, r3
+    sync
+
+    # memory barrier
+    eieio
+    isync
+
+    # restore DBAT 0 and return from interrupt
+    mtdbatu 0, r5
+    mtdbatl 0, r6
+
+    # memory barrier
+    eieio
+    isync
+
+    blr
+

src/main.cpp

@@ -44,6 +44,7 @@ bool CheckRunning() {
 extern "C" int _start(int argc, char **argv) {
     doKernelSetup();
     InitFunctionPointers();
+    doKernelSetup2();
 
     socket_lib_init();
     log_init();
@@ -55,7 +56,6 @@ extern "C" int _start(int argc, char **argv) {
         uint32_t ApplicationMemoryEnd;
 
         asm volatile("lis %0, __CODE_END@h; ori %0, %0, __CODE_END@l" : "=r" (ApplicationMemoryEnd));
-        ModuleData * moduleData = ModuleDataFactory::load("sd:/wiiu/payload.rpx", ApplicationMemoryEnd, 0x01000000 - ApplicationMemoryEnd, gModuleData->trampolines, DYN_LINK_TRAMPOLIN_LIST_LENGTH);
 
         ApplicationMemoryEnd = (ApplicationMemoryEnd + 0x100) & 0xFFFFFF00;
 
@@ -64,6 +64,7 @@ extern "C" int _start(int argc, char **argv) {
         uint32_t moduleDataStartAddress = ((uint32_t) gModuleData + sizeof(module_information_t));
         moduleDataStartAddress = (moduleDataStartAddress + 0x10000) & 0xFFFF0000;
 
+        ModuleData * moduleData = ModuleDataFactory::load("sd:/wiiu/payload.rpx", ApplicationMemoryEnd, 0x00FFF000 - ApplicationMemoryEnd, gModuleData->trampolines, DYN_LINK_TRAMPOLIN_LIST_LENGTH);
         if(moduleData != NULL) {
             DEBUG_FUNCTION_LINE("Loaded module data\n");
             std::vector<RelocationData *> relocData = moduleData->getRelocationDataList();
@@ -103,7 +104,6 @@ extern "C" int _start(int argc, char **argv) {
     return 0;
 }
 
-
 bool doRelocation(std::vector<RelocationData *> &relocData, relocation_trampolin_entry_t * tramp_data, uint32_t tramp_length) {
     for (auto const& curReloc : relocData) {
         RelocationData * cur = curReloc;