Syscalls working as expected

Architecture/amd64/SystemCalls.cpp

@@ -79,7 +79,6 @@ extern "C" __attribute__((naked, used, no_stack_protector)) void SystemCallHandl
 void InitializeSystemCalls()
 {
     wrmsr(MSR_EFER, rdmsr(MSR_EFER) | 1);
-    // TODO: THIS IS NOT WORKING! USER CODE AND USER DATA SHOULD BE CS:0x23 AND SS:0x1B
     wrmsr(MSR_STAR, ((uint64_t)(GDT_KERNEL_CODE) << 32) | ((uint64_t)(GDT_KERNEL_DATA | 3) << 48));
     wrmsr(MSR_LSTAR, (uint64_t)SystemCallHandlerStub);
     wrmsr(MSR_SYSCALL_MASK, (uint64_t)(1 << 9));

Architecture/amd64/SystemCallsAssemblyStub.asm

@@ -7,10 +7,10 @@ SystemCallHandlerStub:
     mov [gs:0x8], rsp   ; CPUData->TempStack
     mov rsp, [gs:0x0]   ; CPUData->SystemCallStack
 
-    push qword 0x23     ; user data segment
+    push qword 0x1b     ; user data segment
     push qword [gs:0x8] ; saved stack
     push r11            ; saved rflags
-    push qword 0x1b     ; user code segment
+    push qword 0x23     ; user code segment
     push rcx            ; Current RIP
 
     cld

Architecture/amd64/cpu/GlobalDescriptorTable.cpp

@@ -44,20 +44,6 @@ namespace GlobalDescriptorTable
          .Flags = {.Raw = 0x0},
          .BaseHigh = 0x0},
 
-        // user code
-        {.Length = 0x0,
-         .BaseLow = 0x0,
-         .BaseMiddle = 0x0,
-         .Access = {.A = 0,
-                    .RW = 1,
-                    .DC = 0,
-                    .E = 1,
-                    .S = 1,
-                    .DPL = 3,
-                    .P = 1},
-         .Flags = {.Unknown = 0x0, .L = 1},
-         .BaseHigh = 0x0},
-
         // user data
         {.Length = 0x0,
          .BaseLow = 0x0,
@@ -72,6 +58,20 @@ namespace GlobalDescriptorTable
          .Flags = {.Raw = 0x0},
          .BaseHigh = 0x0},
 
+        // user code
+        {.Length = 0x0,
+         .BaseLow = 0x0,
+         .BaseMiddle = 0x0,
+         .Access = {.A = 0,
+                    .RW = 1,
+                    .DC = 0,
+                    .E = 1,
+                    .S = 1,
+                    .DPL = 3,
+                    .P = 1},
+         .Flags = {.Unknown = 0x0, .L = 1},
+         .BaseHigh = 0x0},
+
         // tss
         {}};
 

Architecture/amd64/cpu/InterruptDescriptorTable.cpp

@@ -55,16 +55,10 @@ namespace InterruptDescriptorTable
             "pushq %r13\n"
             "pushq %r14\n"
             "pushq %r15\n"
-            // push ds segment
-            "movq %ds, %rax\n"
-            "pushq %rax\n"
 
             "movq %rsp, %rdi\n"
             "call ExceptionHandler\n"
 
-            // pop ds segment
-            "popq %rax\n"
-
             // pop all registers
             "popq %r15\n"
             "popq %r14\n"
@@ -104,16 +98,10 @@ namespace InterruptDescriptorTable
             "pushq %r13\n"
             "pushq %r14\n"
             "pushq %r15\n"
-            // push ds segment
-            "movq %ds, %rax\n"
-            "pushq %rax\n"
 
             "movq %rsp, %rdi\n"
             "call MainInterruptHandler\n"
 
-            // pop ds segment
-            "popq %rax\n"
-
             "popq %r15\n"
             "popq %r14\n"
             "popq %r13\n"

Architecture/amd64/cpu/gdt.hpp

@@ -117,8 +117,8 @@ namespace GlobalDescriptorTable
         GlobalDescriptorTableEntry Null;
         GlobalDescriptorTableEntry Code;
         GlobalDescriptorTableEntry Data;
-        GlobalDescriptorTableEntry UserCode;
         GlobalDescriptorTableEntry UserData;
+        GlobalDescriptorTableEntry UserCode;
         TaskStateSegmentEntry TaskStateSegment;
     } __attribute__((packed)) GlobalDescriptorTableEntries;
 

Core/Crash/CrashHandler.cpp

@@ -348,10 +348,13 @@ namespace CrashHandler
             CPU::x64::CR8 cr8 = CPU::x64::readcr8();
             CPU::x64::EFER efer;
             efer.raw = CPU::x64::rdmsr(CPU::x64::MSR_EFER);
+            uint64_t ds;
+            asmv("mov %%ds, %0"
+                 : "=r"(ds));
 
             EHPrint("\eFF0000FS=%#llx  GS=%#llx  SS=%#llx  CS=%#llx  DS=%#llx\n",
                     CPU::x64::rdmsr(CPU::x64::MSR_FS_BASE), CPU::x64::rdmsr(CPU::x64::MSR_GS_BASE),
-                    Frame->ss, Frame->cs, Frame->ds);
+                    Frame->ss, Frame->cs, ds);
             EHPrint("R8=%#llx  R9=%#llx  R10=%#llx  R11=%#llx\n", Frame->r8, Frame->r9, Frame->r10, Frame->r11);
             EHPrint("R12=%#llx  R13=%#llx  R14=%#llx  R15=%#llx\n", Frame->r12, Frame->r13, Frame->r14, Frame->r15);
             EHPrint("RAX=%#llx  RBX=%#llx  RCX=%#llx  RDX=%#llx\n", Frame->rax, Frame->rbx, Frame->rcx, Frame->rdx);
@@ -402,6 +405,9 @@ namespace CrashHandler
         crashdata.cr4 = CPU::x64::readcr4();
         crashdata.cr8 = CPU::x64::readcr8();
         crashdata.efer.raw = CPU::x64::rdmsr(CPU::x64::MSR_EFER);
+        uint64_t ds;
+        asmv("mov %%ds, %0"
+             : "=r"(ds));
 
         // Get debug registers
         asmv("movq %%dr0, %0"
@@ -458,7 +464,7 @@ namespace CrashHandler
         {
             error("FS=%#llx  GS=%#llx  SS=%#llx  CS=%#llx  DS=%#llx",
                   CPU::x64::rdmsr(CPU::x64::MSR_FS_BASE), CPU::x64::rdmsr(CPU::x64::MSR_GS_BASE),
-                  Frame->ss, Frame->cs, Frame->ds);
+                  Frame->ss, Frame->cs, ds);
             error("R8=%#llx  R9=%#llx  R10=%#llx  R11=%#llx", Frame->r8, Frame->r9, Frame->r10, Frame->r11);
             error("R12=%#llx  R13=%#llx  R14=%#llx  R15=%#llx", Frame->r12, Frame->r13, Frame->r14, Frame->r15);
             error("RAX=%#llx  RBX=%#llx  RCX=%#llx  RDX=%#llx", Frame->rax, Frame->rbx, Frame->rcx, Frame->rdx);

Core/Crash/Screens/Details.cpp

@@ -28,9 +28,20 @@ namespace CrashHandler
                     data.Thread->Name,
                     data.Thread->ID);
         EHPrint("\e7981FCTechnical Informations on CPU %lld:\n", data.ID);
+#if defined(__amd64__)
+        uint64_t ds;
+        asmv("mov %%ds, %0"
+             : "=r"(ds));
+#elif defined(__i386__)
+        uint32_t ds;
+        asmv("mov %%ds, %0"
+             : "=r"(ds));
+#elif defined(__aarch64__)
+#endif
+
         EHPrint("\e7981FCFS=%#llx  GS=%#llx  SS=%#llx  CS=%#llx  DS=%#llx\n",
                 CPU::x64::rdmsr(CPU::x64::MSR_FS_BASE), CPU::x64::rdmsr(CPU::x64::MSR_GS_BASE),
-                data.Frame->ss, data.Frame->cs, data.Frame->ds);
+                data.Frame->ss, data.Frame->cs, ds);
 #if defined(__amd64__)
         EHPrint("R8=%#llx  R9=%#llx  R10=%#llx  R11=%#llx\n", data.Frame->r8, data.Frame->r9, data.Frame->r10, data.Frame->r11);
         EHPrint("R12=%#llx  R13=%#llx  R14=%#llx  R15=%#llx\n", data.Frame->r12, data.Frame->r13, data.Frame->r14, data.Frame->r15);

Core/Crash/UserHandler.cpp

@@ -42,10 +42,20 @@ __no_stack_protector void UserModeExceptionHandler(CHArchTrapFrame *Frame)
         efer.raw = CPU::x64::rdmsr(CPU::x64::MSR_EFER);
 
         error("Technical Informations on CPU %lld:", GetCurrentCPU()->ID);
+#if defined(__amd64__)
+        uint64_t ds;
+        asmv("mov %%ds, %0"
+             : "=r"(ds));
+#elif defined(__i386__)
+        uint32_t ds;
+        asmv("mov %%ds, %0"
+             : "=r"(ds));
+#elif defined(__aarch64__)
+#endif
         error("FS=%#llx GS=%#llx SS=%#llx CS=%#llx DS=%#llx",
               CPU::x64::rdmsr(CPU::x64::MSR_FS_BASE), CPU::x64::rdmsr(CPU::x64::MSR_GS_BASE),
-              Frame->ss, Frame->cs, Frame->ds);
+              Frame->ss, Frame->cs, ds);
-              #if defined(__amd64__)
+#if defined(__amd64__)
         error("R8=%#llx R9=%#llx R10=%#llx R11=%#llx", Frame->r8, Frame->r9, Frame->r10, Frame->r11);
         error("R12=%#llx R13=%#llx R14=%#llx R15=%#llx", Frame->r12, Frame->r13, Frame->r14, Frame->r15);
         error("RAX=%#llx RBX=%#llx RCX=%#llx RDX=%#llx", Frame->rax, Frame->rbx, Frame->rcx, Frame->rdx);

Tasking/Task.cpp

@@ -362,9 +362,12 @@ namespace Tasking
             schedbg("================================================================");
             schedbg("Status: 0-ukn | 1-rdy | 2-run | 3-wait | 4-term");
             schedbg("Technical Informations on regs %#lx", Frame->InterruptNumber);
+            uint64_t ds;
+            asmv("mov %%ds, %0"
+                 : "=r"(ds));
             schedbg("FS=%#lx  GS=%#lx  SS=%#lx  CS=%#lx  DS=%#lx",
                     CPU::x64::rdmsr(CPU::x64::MSR_FS_BASE), CPU::x64::rdmsr(CPU::x64::MSR_GS_BASE),
-                    Frame->ss, Frame->cs, Frame->ds);
+                    Frame->ss, Frame->cs, ds);
             schedbg("R8=%#lx  R9=%#lx  R10=%#lx  R11=%#lx",
                     Frame->r8, Frame->r9, Frame->r10, Frame->r11);
             schedbg("R12=%#lx  R13=%#lx  R14=%#lx  R15=%#lx",
@@ -486,8 +489,8 @@ namespace Tasking
                 CurrentCPU->CurrentThread->Registers.ss != GDT_USER_DATA)
             {
                 warn("Wrong CS or SS for user process! (Code:%#lx, Data:%#lx != Code:%#lx, Data:%#lx)",
-                        CurrentCPU->CurrentThread->Registers.cs, CurrentCPU->CurrentThread->Registers.ss,
+                     CurrentCPU->CurrentThread->Registers.cs, CurrentCPU->CurrentThread->Registers.ss,
-                        GDT_USER_CODE, GDT_USER_DATA);
+                     GDT_USER_CODE, GDT_USER_DATA);
                 CurrentCPU->CurrentThread->Registers.cs = GDT_USER_CODE;
                 CurrentCPU->CurrentThread->Registers.ss = GDT_USER_DATA;
             }
@@ -498,8 +501,8 @@ namespace Tasking
                 CurrentCPU->CurrentThread->Registers.ss != GDT_KERNEL_DATA)
             {
                 warn("Wrong CS or SS for kernel process! (Code:%#lx, Data:%#lx != Code:%#lx, Data:%#lx",
-                        CurrentCPU->CurrentThread->Registers.cs, CurrentCPU->CurrentThread->Registers.ss,
+                     CurrentCPU->CurrentThread->Registers.cs, CurrentCPU->CurrentThread->Registers.ss,
-                        GDT_KERNEL_CODE, GDT_KERNEL_DATA);
+                     GDT_KERNEL_CODE, GDT_KERNEL_DATA);
                 CurrentCPU->CurrentThread->Registers.cs = GDT_KERNEL_CODE;
                 CurrentCPU->CurrentThread->Registers.ss = GDT_KERNEL_DATA;
             }
@@ -553,9 +556,12 @@ namespace Tasking
         {
             schedbg("================================================================");
             schedbg("Technical Informations on Thread %s[%ld]:", CurrentCPU->CurrentThread->Name, CurrentCPU->CurrentThread->ID);
+            uint64_t ds;
+            asmv("mov %%ds, %0"
+                 : "=r"(ds));
             schedbg("FS=%#lx  GS=%#lx  SS=%#lx  CS=%#lx  DS=%#lx",
                     CPU::x64::rdmsr(CPU::x64::MSR_FS_BASE), CPU::x64::rdmsr(CPU::x64::MSR_GS_BASE),
-                    Frame->ss, Frame->cs, Frame->ds);
+                    Frame->ss, Frame->cs, ds);
             schedbg("R8=%#lx  R9=%#lx  R10=%#lx  R11=%#lx",
                     Frame->r8, Frame->r9, Frame->r10, Frame->r11);
             schedbg("R12=%#lx  R13=%#lx  R14=%#lx  R15=%#lx",
@@ -725,7 +731,6 @@ namespace Tasking
             Thread->GSBase = CPU::x64::rdmsr(CPU::x64::MSRID::MSR_GS_BASE);
             Thread->FSBase = CPU::x64::rdmsr(CPU::x64::MSRID::MSR_FS_BASE);
             Thread->Registers.cs = GDT_KERNEL_CODE;
-            Thread->Registers.ds = GDT_KERNEL_DATA;
             Thread->Registers.ss = GDT_KERNEL_DATA;
             Thread->Registers.rflags.AlwaysOne = 1;
             Thread->Registers.rflags.IF = 1;
@@ -744,7 +749,6 @@ namespace Tasking
             Thread->GSBase = 0;
             Thread->FSBase = 0;
             Thread->Registers.cs = GDT_USER_CODE;
-            Thread->Registers.ds = GDT_USER_DATA;
             Thread->Registers.ss = GDT_USER_DATA;
             Thread->Registers.rflags.AlwaysOne = 1;
             // Thread->Registers.rflags.PF = 1;

include/cpu.hpp

@@ -312,11 +312,6 @@ namespace CPU
 
         typedef struct TrapFrame
         {
-            // uint32_t gs;  // General-purpose Segment
-            // uint32_t fs;  // General-purpose Segment
-            // uint32_t es;  // Extra Segment (used for string operations)
-            uint32_t ds; // Data Segment
-
             uint32_t ebp; // Base Pointer (meant for stack frames)
             uint32_t edi; // Destination index for string operations
             uint32_t esi; // Source index for string operations
@@ -1396,11 +1391,6 @@ namespace CPU
 
         typedef struct TrapFrame
         {
-            // uint64_t gs;  // General-purpose Segment
-            // uint64_t fs;  // General-purpose Segment
-            // uint64_t es;  // Extra Segment (used for string operations)
-            uint64_t ds; // Data Segment
-
             uint64_t r15; // General purpose
             uint64_t r14; // General purpose
             uint64_t r13; // General purpose