Bugfixing a hidden bug in vm8086 (to help trace a tcp bug)

[tpg/acess2.git] / Kernel / arch / x86 / mm_virt.c

diff --git a/Kernel/arch/x86/mm_virt.c b/Kernel/arch/x86/mm_virt.c
index 8882f38..8c59ea0 100644 (file)
--- a/Kernel/arch/x86/mm_virt.c
+++ b/Kernel/arch/x86/mm_virt.c
@@ -55,6 +55,7 @@
 #define        PF_PRESENT      0x1
 #define        PF_WRITE        0x2
 #define        PF_USER         0x4
+#define PF_GLOBAL      0x80
 #define        PF_COW          0x200
 #define        PF_NOPAGE       0x400
 
@@ -78,6 +79,7 @@ void  MM_PreinitVirtual(void);
 void   MM_InstallVirtual(void);
 void   MM_PageFault(tVAddr Addr, Uint ErrorCode, tRegs *Regs);
 void   MM_DumpTables(tVAddr Start, tVAddr End);
+tVAddr MM_ClearUser(void);
 tPAddr MM_DuplicatePage(tVAddr VAddr);
 
 // === GLOBALS ===
@@ -217,6 +219,9 @@ void MM_PageFault(tVAddr Addr, Uint ErrorCode, tRegs *Regs)
                        );
                Warning("User Pagefault: Instruction at %04x:%08x accessed %p", Regs->cs, Regs->eip, Addr);
                __asm__ __volatile__ ("sti");   // Restart IRQs
+               #if 1
+               Error_Backtrace(Regs->eip, Regs->ebp);
+               #endif
                Threads_SegFault(Addr);
                return ;
        }
@@ -272,7 +277,7 @@ void MM_DumpTables(tVAddr Start, tVAddr End)
        tPAddr  expected = 0;
        tVAddr  curPos;
        Uint    page;
-       const tPAddr    MASK = ~0xF98;
+       const tPAddr    MASK = ~0xF78;
        
        Start >>= 12;   End >>= 12;
        
@@ -302,14 +307,16 @@ void MM_DumpTables(tVAddr Start, tVAddr End)
                ||  (gaPageTable[page] & MASK) != expected)
                {
                        if(expected) {
-                               Log(" 0x%08x-0x%08x => 0x%08x-0x%08x (%s%s%s%s)",
-                                       rangeStart, curPos - 1,
+                               Log(" 0x%08x => 0x%08x - 0x%08x (%s%s%s%s%s)",
+                                       rangeStart,
                                        gaPageTable[rangeStart>>12] & ~0xFFF,
-                                       (expected & ~0xFFF) - 1,
+                                       curPos - rangeStart,
                                        (expected & PF_NOPAGE ? "P" : "-"),
                                        (expected & PF_COW ? "C" : "-"),
+                                       (expected & PF_GLOBAL ? "G" : "-"),
                                        (expected & PF_USER ? "U" : "-"),
-                                       (expected & PF_WRITE ? "W" : "-")
+                                       (expected & PF_WRITE ? "W" : "-"),
+                                       gaPageTable[page] & MASK, expected
                                        );
                                expected = 0;
                        }
@@ -323,10 +330,10 @@ void MM_DumpTables(tVAddr Start, tVAddr End)
        }
        
        if(expected) {
-               Log("0x%08x-0x%08x => 0x%08x-0x%08x (%s%s%s%s)",
-                       rangeStart, curPos - 1,
+               Log("0x%08x => 0x%08x - 0x%08x (%s%s%s%s)",
+                       rangeStart,
                        gaPageTable[rangeStart>>12] & ~0xFFF,
-                       (expected & ~0xFFF) - 1,
+                       curPos - rangeStart,
                        (expected & PF_NOPAGE ? "p" : "-"),
                        (expected & PF_COW ? "C" : "-"),
                        (expected & PF_USER ? "U" : "-"),
@@ -660,14 +667,28 @@ tVAddr MM_NewKStack(void)
        Uint    i;
        for(base = KERNEL_STACKS; base < KERNEL_STACKS_END; base += KERNEL_STACK_SIZE)
        {
+               // Check if space is free
                if(MM_GetPhysAddr(base) != 0)   continue;
-               for(i = 0; i < KERNEL_STACK_SIZE; i += 0x1000) {
-                       MM_Allocate(base+i);
+               // Allocate
+               //for(i = KERNEL_STACK_SIZE; i -= 0x1000 ; )
+               for(i = 0; i < KERNEL_STACK_SIZE; i += 0x1000 )
+               {
+                       if( MM_Allocate(base+i) == 0 )
+                       {
+                               // On error, print a warning and return error
+                               Warning("MM_NewKStack - Out of memory");
+                               // - Clean up
+                               //for( i += 0x1000 ; i < KERNEL_STACK_SIZE; i += 0x1000 )
+                               //      MM_Deallocate(base+i);
+                               return 0;
+                       }
                }
+               // Success
                Log("MM_NewKStack - Allocated %p", base + KERNEL_STACK_SIZE);
                return base+KERNEL_STACK_SIZE;
        }
-       Warning("MM_NewKStack - No address space left\n");
+       // No stacks left
+       Warning("MM_NewKStack - No address space left");
        return 0;
 }