patch-1.3.53 linux/arch/ppc/mm/fault.c

• Lines: 255
• Date: Sat Dec 30 15:48:22 1995
• Orig file: v1.3.52/linux/arch/ppc/mm/fault.c
• Orig date: Mon Nov 27 12:48:27 1995

diff -u --recursive --new-file v1.3.52/linux/arch/ppc/mm/fault.c linux/arch/ppc/mm/fault.c
@@ -1,3 +1,4 @@
+/* * Last edited: Nov 29 18:14 1995 (cort) */
 /*
  *  ARCH/ppc/mm/fault.c
  *
@@ -5,6 +6,9 @@
  *  Ported to PPC by Gary Thomas
  */
 
+/*#define NOISY_DATAFAULT*/
+/*#define NOISY_INSTRFAULT*/
+
 #include <linux/config.h>
 #include <linux/signal.h>
 #include <linux/sched.h>
@@ -37,19 +41,24 @@
   if (user_mode(regs)) mode |= 0x04;
   if (regs->dsisr & 0x02000000) mode |= 0x02;  /* Load/store */
   if (regs->dsisr & 0x08000000) mode |= 0x01;  /* Protection violation */
-#if 0
-  /*#ifdef SHOW_FAULTS*/
-  printk("Data Access Fault - Loc: %x, DSISR: %x, PC: %x", regs->dar, regs->dsisr, regs->nip);
-  printk(" PR: %d\n", regs->msr &&(1<<14));
+#ifdef NOISY_DATAFAULT
+  printk("Data fault on %x\n",regs->dar);
 #endif
   if (mode & 0x01)
   {
 #if 0
     printk("Write Protect Fault - Loc: %x, DSISR: %x, PC: %x\n", regs->dar, regs->dsisr, regs->nip);
 #endif
+#ifdef NOISY_DATAFAULT
+    printk("Write Protect fault\n ");
+#endif
     do_page_fault(regs, regs->dar, mode);
+#ifdef NOISY_DATAFAULT    
+    printk("Write Protect fault handled\n");
+#endif
     return;
   }
+/*   printk("trying\n"); */
   for (tries = 0;  tries < 1;  tries++)
   {
     dir = pgd_offset(current->mm, regs->dar & PAGE_MASK);
@@ -72,7 +81,15 @@
     {
       printk("No PGD\n");
     }
+#ifdef NOISY_DATAFAULT    
+    printk("fall through page fault addr=%x; ip=%x\n",
+	   regs->dar,regs->nip);
+    printk("beforefault: pgd[0] = %x[%x]\n",current->mm->pgd,*(current->mm->pgd));
+#endif
     do_page_fault(regs, regs->dar, mode);
+#ifdef NOISY_DATAFAULT    
+    printk("handled: pgd[0] = %x[%x]\n",current->mm->pgd,*(current->mm->pgd));
+#endif
   }
 }
 
@@ -83,43 +100,72 @@
   pmd_t *pmd;
   pte_t *pte;
   int tries, mode = 0;
-#if 0
-  panic("Instruction Access Fault - Loc: %x, DSISR: %x, PC: %x\n", regs->dar, regs->dsisr, regs->nip);
-#endif	
+  
+#if NOISY_INSTRFAULT
+  printk("Instr fault on %x\n",regs->dar);
+#endif
   if (user_mode(regs)) mode |= 0x04;
   if (regs->dsisr & 0x02000000) mode |= 0x02;  /* Load/store */
   if (regs->dsisr & 0x08000000) mode |= 0x01;  /* Protection violation */
+  
   if (mode & 0x01)
   {
-    do_page_fault(regs, regs->dar, mode);
+    do_page_fault(regs, regs->dar, mode); 
     return;
   }
   for (tries = 0;  tries < 1;  tries++)
   {
+    /*     dir = pgd_offset(current->mm, regs->nip & PAGE_MASK); */
     dir = pgd_offset(current->mm, regs->dar & PAGE_MASK);
+#ifdef NOISY_INSTRFAULT
+/*	printk("regs->dar=%x current=%x current->mm=%x current->mm->pgd=%x current->tss.pg_tables=%x\n",
+	       regs->dar,current,current->mm,current->mm->pgd,current->tss.pg_tables);*/
+#endif
     if (dir)
     {
-      pmd = pmd_offset(dir, regs->dar & PAGE_MASK);
+      pmd = pmd_offset(dir, regs->dar & PAGE_MASK); 
       if (pmd && pmd_present(*pmd))
       {
-	pte = pte_offset(pmd, regs->dar & PAGE_MASK);
-	if (pte && pte_present(*pte))
-	{
+ 	pte = pte_offset(pmd, regs->dar & PAGE_MASK); 
+
+#ifdef NOISY_INSTRFAULT
+/*	printk("dir %x(%x) pmd %x(%x) pte %x\n",dir,*dir,pmd,*pmd,pte);*/
 #if 0
-	  printk("Page mapped - PTE: %x[%x]\n", pte, *(long *)pte);
+	printk("pgd_offset mm=%x mm->pgd=%x dirshouldbe=%x\n",
+	       current->mm, current->mm->pgd,
+	       current->mm->pgd+((regs->dar&PAGE_MASK) >> PGDIR_SHIFT));
+	printk("dir is %x\n", dir);
+	
+	/* 	printk("got pte\n"); */
+	if (pte) {
+	  printk("pgd=%x; dir=%x->%x; pmd=%x->%x; pte=%x; \n",
+		 current->mm->pgd,dir,*dir,pmd,*pmd,pte);
+	  if (pte_present(*pte)) {
+	    printk("pte present\n");
+	  } else {
+	    printk("pte not present\n");
+	  }
+	} else {
+	  printk("pte false\n");
+	}
 #endif
-	  MMU_hash_page(&current->tss, regs->dar & PAGE_MASK, pte);
+#endif
+	if (pte && pte_present(*pte))
+	{
+/* 	  MMU_hash_page(&current->tss, regs->nip & PAGE_MASK, pte); */
+ 	  MMU_hash_page(&current->tss, regs->dar & PAGE_MASK, pte); 
 	  return;
 	}
       }
     } else
     {
-#if 1
-  panic("No PGD Instruction Access Fault - Loc: %x, DSISR: %x, PC: %x\n", regs->dar, regs->dsisr, regs->nip);
-#endif	
-      printk("No PGD\n");
+#ifdef NOISY_INSTRFAULT      
+      panic("No PGD Instruction Access Fault - Loc: %x, DSISR: %x, PC: %x current->mm\n",
+	    regs->dar, regs->dsisr, regs->nip, current->mm);
+#endif
     }
-    do_page_fault(regs, regs->dar, mode);
+/*     do_page_fault(regs, regs->nip, mode); */
+     do_page_fault(regs, regs->dar, mode);
   }
 }
 
@@ -138,24 +184,15 @@
 {
   struct vm_area_struct * vma;
   unsigned long page;
-/*  printk("\ndo_page_fault()\n");*/
+
+/*   printk("In do_page_fault()\n"); */
 #if 1
   for (vma = current->mm->mmap ; ; vma = vma->vm_next)
   {
     if (!vma)
     {
-#if 0 /* mfisk */
-        {   struct vm_area_struct * mmp;
-
-          for(mmp=current->mm->mmap; mmp; mmp=mmp->vm_next) {
-            printk("notinmap: current: %x; mm: %x; mmap: %x; vma: %x to %x flags: %x\n",
-                   current, current->mm, mmp, mmp->vm_start, mmp->vm_end, mmp->vm_flags);
-          }
-        }
-#endif
-       panic("do_page_fault()  !vma \n");
-      panic("not in map: ip = %x; current=%x; mm=%x; mmap=%x; address = %x error_code = %x\n",
-	    regs->nip, current, current->mm, current->mm->mmap, address, error_code);
+      panic("!vma: ip = %x; current=%x[%d]; mm=%x; mmap=%x; address = %x error_code = %x\n",
+	    regs->nip, current,current->pid,current->mm,current->mm->mmap, address, error_code);
       goto bad_area;
     }
     if (vma->vm_end > address)
@@ -164,6 +201,8 @@
 #else
   vma = find_vma(current, address);
   if (!vma)
+  {
+  }
     goto bad_area;
 #endif
   if (vma->vm_start <= address){
@@ -171,13 +210,19 @@
   }
   if (!(vma->vm_flags & VM_GROWSDOWN))
   {
+    printk("stack: gpr[1]=%x ip = %x; current=%x[%d]; mm=%x; mmap=%x; address = %x error_code = %x\n",regs->gpr[1],regs->nip, current,current->pid,current->mm,current->mm->mmap, address, error_code);
     panic("stack\n");
     goto bad_area;
   }
   if (vma->vm_end - address > current->rlim[RLIMIT_STACK].rlim_cur)
-  {    panic("stack 2\n");
+  {
+    printk("stack2: vma->vm_end-addres %x rlim %x\n", vma->vm_end - address,
+	   current->rlim[RLIMIT_STACK].rlim_cur);
+    printk("stack2: vm_end %x address = %x\n", vma->vm_end,address);
+    printk("stack2: gpr[1]=%x ip = %x; current=%x[%d]; mm=%x; mmap=%x; address = %x error_code = %x\n",regs->gpr[1],regs->nip, current,current->pid,current->mm,current->mm->mmap, address, error_code);
+    panic("stack2\n");
     goto bad_area;
-     }
+  }
   vma->vm_offset -= vma->vm_start - (address & PAGE_MASK);
   vma->vm_start = (address & PAGE_MASK);
   
@@ -192,8 +237,8 @@
   if (error_code & 2) {
     if (!(vma->vm_flags & VM_WRITE))
     {
-      panic("\ndo_page_fault()  write\n");
-      panic("\ndo_page_fault() write! current: %x, address:%x, vm_flags: %x, mm: %x; vma(%x) %x to %x\n",
+      panic("do_page_fault()  write\n");
+      panic("do_page_fault() write! current: %x, address:%x, vm_flags: %x, mm: %x; vma(%x) %x to %x\n",
 	    current,address,vma->vm_flags,current->mm,vma,vma->vm_start,vma->vm_end);
       goto bad_area;
     }
@@ -224,7 +269,10 @@
       goto bad_area; 
     }
   }
+/*   printk("premm: pgd[0] = %x[%x]\n",current->mm->pgd,*(current->mm->pgd)); */
   handle_mm_fault(vma, address, error_code & 2); 
+/*   printk("handled fault for %x in %x to %x flags %x\n", */
+/* 	 address,vma->vm_start,vma->vm_end,vma->vm_flags); */
   return;
   
   /*
@@ -233,16 +281,21 @@
    */
 bad_area:
   if (user_mode(regs)) {
-    panic("Task: %x, PC: %x, bad area! - Addr: %x\n", current, regs->nip, address);
+    printk("Task: %x, PC: %x, bad area! - Addr: %x\n", current, regs->nip, address);
     send_sig(SIGSEGV, current, 1);
     return;
   }
 #if 0
-  panic("\nKERNEL! Task: %x, PC: %x, bad area! - Addr: %x, PGDIR: %x\n",
+  panic("KERNEL! Task: %x, PC: %x, bad area! - Addr: %x, PGDIR: %x\n",
 	 current, regs->nip, address, current->tss.pg_tables);
 #else
-  panic("\nKERNELmm! current: %x, address:%x, vm_flags: %x, mm: %x; vma(%x) %x to %x\n",
+  /*  panic("KERNEL mm! current: %x,  address:%x, vm_flags: %x, mm: %x; \nvma(%x) %x to %x swapper_pg_dir %x\n",
+	current,address,vma->vm_flags,current->mm,vma,vma->vm_start,vma->vm_end,
+	swapper_pg_dir);*/
+  printk("KERNEL mm! current: %x,  address:%x, vm_flags: %x, mm: %x; vma(%x) %x to %x\n",
 	current,address,vma->vm_flags,current->mm,vma,vma->vm_start,vma->vm_end);
+  panic("Kernel access of bad area\n");
+	 
 #endif
   
   while (1) ;