1 files changed, 21 insertions, 40 deletions

diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
index 0048eadd0681..bd0f4821f7e1 100644
--- a/arch/arm/mm/fault.c
+++ b/arch/arm/mm/fault.c
@@ -27,43 +27,20 @@
 
 #ifdef CONFIG_MMU
 
-#ifdef CONFIG_KPROBES
-static inline int notify_page_fault(struct pt_regs *regs, unsigned int fsr)
-{
-	int ret = 0;
-
-	if (!user_mode(regs)) {
-		/* kprobe_running() needs smp_processor_id() */
-		preempt_disable();
-		if (kprobe_running() && kprobe_fault_handler(regs, fsr))
-			ret = 1;
-		preempt_enable();
-	}
-
-	return ret;
-}
-#else
-static inline int notify_page_fault(struct pt_regs *regs, unsigned int fsr)
-{
-	return 0;
-}
-#endif
-
 /*
  * This is useful to dump out the page tables associated with
  * 'addr' in mm 'mm'.
  */
-void show_pte(struct mm_struct *mm, unsigned long addr)
+void show_pte(const char *lvl, struct mm_struct *mm, unsigned long addr)
 {
 	pgd_t *pgd;
 
 	if (!mm)
 		mm = &init_mm;
 
-	pr_alert("pgd = %p\n", mm->pgd);
+	printk("%spgd = %p\n", lvl, mm->pgd);
 	pgd = pgd_offset(mm, addr);
-	pr_alert("[%08lx] *pgd=%08llx",
-			addr, (long long)pgd_val(*pgd));
+	printk("%s[%08lx] *pgd=%08llx", lvl, addr, (long long)pgd_val(*pgd));
 
 	do {
 		pud_t *pud;
@@ -118,7 +95,7 @@ void show_pte(struct mm_struct *mm, unsigned long addr)
 	pr_cont("\n");
 }
 #else					/* CONFIG_MMU */
-void show_pte(struct mm_struct *mm, unsigned long addr)
+void show_pte(const char *lvl, struct mm_struct *mm, unsigned long addr)
 { }
 #endif					/* CONFIG_MMU */
 
@@ -139,11 +116,12 @@ __do_kernel_fault(struct mm_struct *mm, unsigned long addr, unsigned int fsr,
 	 * No handler, we'll have to terminate things with extreme prejudice.
 	 */
 	bust_spinlocks(1);
+	pr_alert("8<--- cut here ---\n");
 	pr_alert("Unable to handle kernel %s at virtual address %08lx\n",
 		 (addr < PAGE_SIZE) ? "NULL pointer dereference" :
 		 "paging request", addr);
 
-	show_pte(mm, addr);
+	show_pte(KERN_ALERT, mm, addr);
 	die("Oops", regs, fsr);
 	bust_spinlocks(0);
 	do_exit(SIGKILL);
@@ -154,19 +132,21 @@ __do_kernel_fault(struct mm_struct *mm, unsigned long addr, unsigned int fsr,
  * User mode accesses just cause a SIGSEGV
  */
 static void
-__do_user_fault(struct task_struct *tsk, unsigned long addr,
-		unsigned int fsr, unsigned int sig, int code,
-		struct pt_regs *regs)
+__do_user_fault(unsigned long addr, unsigned int fsr, unsigned int sig,
+		int code, struct pt_regs *regs)
 {
+	struct task_struct *tsk = current;
+
 	if (addr > TASK_SIZE)
 		harden_branch_predictor();
 
 #ifdef CONFIG_DEBUG_USER
 	if (((user_debug & UDBG_SEGV) && (sig == SIGSEGV)) ||
 	    ((user_debug & UDBG_BUS)  && (sig == SIGBUS))) {
-		printk(KERN_DEBUG "%s: unhandled page fault (%d) at 0x%08lx, code 0x%03x\n",
+		pr_err("8<--- cut here ---\n");
+		pr_err("%s: unhandled page fault (%d) at 0x%08lx, code 0x%03x\n",
 		       tsk->comm, sig, addr, fsr);
-		show_pte(tsk->mm, addr);
+		show_pte(KERN_ERR, tsk->mm, addr);
 		show_regs(regs);
 	}
 #endif
@@ -180,7 +160,7 @@ __do_user_fault(struct task_struct *tsk, unsigned long addr,
 	tsk->thread.address = addr;
 	tsk->thread.error_code = fsr;
 	tsk->thread.trap_no = 14;
-	force_sig_fault(sig, code, (void __user *)addr, tsk);
+	force_sig_fault(sig, code, (void __user *)addr);
 }
 
 void do_bad_area(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
@@ -193,7 +173,7 @@ void do_bad_area(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
 	 * have no context to handle this fault with.
 	 */
 	if (user_mode(regs))
-		__do_user_fault(tsk, addr, fsr, SIGSEGV, SEGV_MAPERR, regs);
+		__do_user_fault(addr, fsr, SIGSEGV, SEGV_MAPERR, regs);
 	else
 		__do_kernel_fault(mm, addr, fsr, regs);
 }
@@ -211,7 +191,7 @@ static inline bool access_error(unsigned int fsr, struct vm_area_struct *vma)
 {
 	unsigned int mask = VM_READ | VM_WRITE | VM_EXEC;
 
-	if (fsr & FSR_WRITE)
+	if ((fsr & FSR_WRITE) && !(fsr & FSR_CM))
 		mask = VM_WRITE;
 	if (fsr & FSR_LNX_PF)
 		mask = VM_EXEC;
@@ -263,7 +243,7 @@ do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
 	vm_fault_t fault;
 	unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
 
-	if (notify_page_fault(regs, fsr))
+	if (kprobe_page_fault(regs, fsr))
 		return 0;
 
 	tsk = current;
@@ -282,7 +262,7 @@ do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
 
 	if (user_mode(regs))
 		flags |= FAULT_FLAG_USER;
-	if (fsr & FSR_WRITE)
+	if ((fsr & FSR_WRITE) && !(fsr & FSR_CM))
 		flags |= FAULT_FLAG_WRITE;
 
 	/*
@@ -389,7 +369,7 @@ retry:
 			SEGV_ACCERR : SEGV_MAPERR;
 	}
 
-	__do_user_fault(tsk, addr, fsr, sig, code, regs);
+	__do_user_fault(addr, fsr, sig, code, regs);
 	return 0;
 
 no_context:
@@ -553,9 +533,10 @@ do_DataAbort(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
 	if (!inf->fn(addr, fsr & ~FSR_LNX_PF, regs))
 		return;
 
+	pr_alert("8<--- cut here ---\n");
 	pr_alert("Unhandled fault: %s (0x%03x) at 0x%08lx\n",
 		inf->name, fsr, addr);
-	show_pte(current->mm, addr);
+	show_pte(KERN_ALERT, current->mm, addr);
 
 	arm_notify_die("", regs, inf->sig, inf->code, (void __user *)addr,
 		       fsr, 0);