better panic

Reviewed-on: #9

debug.gdb

@@ -1,3 +1,3 @@
 target remote localhost:1234
 set disassembly-flavor intel
-display/8i $rip
+display/4i $rip

src/config.h

@@ -16,6 +16,8 @@
 /* process */
 #define PROCESS_NAME_MAX 64
 #define PROCESS_STACK_SIZE 0x10000 // 64kb
+#define PROCESS_BASE 0x400000
+#define PROCESS_STACK_BASE 0x1000000
 
 /* sched */
 // 1 tick = 1 ms => quantum = 10ms
@@ -32,4 +34,4 @@
 /* term */
 #define TERM_HISTORY_MAX_LINES 256
 
-#endif
+#endif

src/idt/idt.c

@@ -87,11 +87,7 @@ static void page_fault_handler(struct cpu_status_t* ctx)
     CHECK_BIT(ctx->error_code, 7) ? " SGX_VIOLATION" : "",
     cr2);
 
-    /* if (CHECK_BIT(ctx->error_code, 0))
+    panic(ctx, "page fault");
-    {
-        panic(ctx);
-    } */
-    panic(ctx);
 }
 
 static void gp_fault_handler(struct cpu_status_t* ctx)
@@ -117,7 +113,7 @@ static void gp_fault_handler(struct cpu_status_t* ctx)
         index);
     }
 
-    panic(ctx);
+    panic(ctx, "gp fault");
 }
 
 struct cpu_status_t* interrupt_dispatch(struct cpu_status_t* context)
@@ -217,4 +213,4 @@ struct cpu_status_t* interrupt_dispatch(struct cpu_status_t* context)
     }
 
     return context;
-}
+}

src/kernel.h

@@ -22,11 +22,13 @@ enum ErrorCodes
 
 #define DEBUG(log, ...) fctprintf((void*)&skputc, 0, "debug: [%s]: " log "\r\n", __FILE__, ##__VA_ARGS__)
 
+#define DIE_DEBUG(str) fctprintf((void*)&skputc, 0, str)
+
 #define CHECK_BIT(var,pos) ((var) & (1<<(pos)))
 
 // printf("debug: [%s]: " log "\n", __FILE__, ##__VA_ARGS__);
 
-void panic(struct cpu_status_t* ctx);
+void panic(struct cpu_status_t* ctx, const char* str);
 void hcf();
 #define assert(check) do { if(!(check)) hcf(); } while(0)
 

src/kmain.c

@@ -37,8 +37,17 @@ void hcf()
 // Doing nothing (can be interrupted)
 void idle() {for(;;)asm("hlt");}
 
-void panic(struct cpu_status_t* ctx)
+void panic(struct cpu_status_t* ctx, const char* str)
 {
+	CLEAR_INTERRUPTS;
+	if (ctx == NULL)
+	{
+		DEBUG("\x1b[38;5;231m\x1b[48;5;196mKernel panic!!!\x1b[0m Something went horribly wrong! (no cpu ctx)");
+		DIE_DEBUG(str);
+		skputc('\n');
+		DEBUG("\x1b[38;5;231m\x1b[48;5;196mend Kernel panic - halting...\x1b[0m");
+		hcf();
+	}
 	DEBUG("\x1b[38;5;231m\x1b[48;5;196mKernel panic!!!\x1b[0m at rip=%p\nSomething went horribly wrong! vect=0x%.2x errcode=0x%x\n\rrax=%p rbx=%p rcx=%p rdx=%p\n\rrsi=%p rdi=%p  r8=%p  r9=%p\n\rr10=%p r11=%p r12=%p r13=%p\n\rr14=%p r15=%p\n\n\rflags=%p\n\rstack at rbp=%p\n\rHalting...",
 		ctx->iret_rip,
 		ctx->vector_number, ctx->error_code, ctx->rax, ctx->rbx, ctx->rcx, ctx->rdx, ctx->rsi, ctx->rdi,
@@ -59,7 +68,7 @@ extern struct process_t* current_process;
 
 void pedicel_main(void* arg)
 {
-	
+	panic(NULL, "we did it!");
 }
 
 void two_main(void* arg)
@@ -104,8 +113,8 @@ void kmain()
 	vmm_init();
 	
 	struct process_t* pedicel = process_create("pedicel", (void*)pedicel_main, 0);
-	struct process_t* two = process_create("two", (void*)two_main, 0);
+	//struct process_t* two = process_create("two", (void*)two_main, 0);
-	struct process_t* three = process_create("three", (void*)three_main, 0);
+	//struct process_t* three = process_create("three", (void*)three_main, 0);
 	process_display_list(processes_list);
 
 	scheduler_init();

src/mem/paging/pmm.c

@@ -66,7 +66,10 @@ static uintptr_t g_freelist = 0;
 
 uintptr_t pmm_alloc()
 {
-    if (!g_freelist) return 0;
+    if (!g_freelist)
+	{
+		panic(NULL, "PMM is out of memory!");		
+	}
     uintptr_t addr = g_freelist;
     g_freelist = *(uintptr_t*) PHYS_TO_VIRT(g_freelist);
     return addr;
@@ -104,4 +107,4 @@ void pmm_init(struct limine_memmap_response* memmap, struct limine_hhdm_response
     // Now we have biggest USABLE region,
     // so to populate the free list we just iterate through it
     pmm_init_freelist();
-}
+}

src/sched/process.h

@@ -24,6 +24,7 @@ struct process_t
 
     status_t status;
     struct cpu_status_t* context;
+	void* root_page_table; // Process PML4 (should contain kernel PML4 in higher half [256-511]
     struct process_t* next;
 };
 

src/sched/task.S

@@ -0,0 +1,7 @@
+; Task (process) switching
+
+bits 64
+
+global switch_to_task
+switch_to_task:
+