1 files changed, 58 insertions, 36 deletions

diff --git a/arch/blackfin/kernel/traps.c b/arch/blackfin/kernel/traps.c
index 56a67ab698c7..5b847070dae5 100644
--- a/arch/blackfin/kernel/traps.c
+++ b/arch/blackfin/kernel/traps.c
@@ -67,6 +67,8 @@ void __init trap_init(void)
         CSYNC();
 }
 
+void *saved_icplb_fault_addr, *saved_dcplb_fault_addr;
+
 int kstack_depth_to_print = 48;
 
 static void decode_address(char *buf, unsigned long address)
@@ -75,7 +77,7 @@ static void decode_address(char *buf, unsigned long address)
         struct task_struct *p;
         struct mm_struct *mm;
         unsigned long flags, offset;
-        unsigned int in_exception = bfin_read_IPEND() & 0x10;
+        unsigned char in_atomic = (bfin_read_IPEND() & 0x10) || in_atomic();
 
 #ifdef CONFIG_KALLSYMS
         unsigned long symsize;
@@ -117,7 +119,7 @@ static void decode_address(char *buf, unsigned long address)
          */
         write_lock_irqsave(&tasklist_lock, flags);
         for_each_process(p) {
-                mm = (in_exception ? p->mm : get_task_mm(p));
+                mm = (in_atomic ? p->mm : get_task_mm(p));
                 if (!mm)
                         continue;
 
@@ -137,23 +139,36 @@ static void decode_address(char *buf, unsigned long address)
                                 /* FLAT does not have its text aligned to the start of
                                  * the map while FDPIC ELF does ...
                                  */
-                                if (current->mm &&
-                                    (address > current->mm->start_code) &&
-                                    (address < current->mm->end_code))
-                                        offset = address - current->mm->start_code;
-                                else
-                                        offset = (address - vma->vm_start) + (vma->vm_pgoff << PAGE_SHIFT);
-
-                                sprintf(buf, "<0x%p> [ %s + 0x%lx ]",
-                                        (void *)address, name, offset);
-                                if (!in_exception)
+
+                                /* before we can check flat/fdpic, we need to
+                                 * make sure current is valid
+                                 */
+                                if ((unsigned long)current >= FIXED_CODE_START &&
+                                    !((unsigned long)current & 0x3)) {
+                                        if (current->mm &&
+                                            (address > current->mm->start_code) &&
+                                            (address < current->mm->end_code))
+                                                offset = address - current->mm->start_code;
+                                        else
+                                                offset = (address - vma->vm_start) +
+                                                         (vma->vm_pgoff << PAGE_SHIFT);
+
+                                        sprintf(buf, "<0x%p> [ %s + 0x%lx ]",
+                                                (void *)address, name, offset);
+                                } else
+                                        sprintf(buf, "<0x%p> [ %s vma:0x%lx-0x%lx]",
+                                                (void *)address, name,
+                                                vma->vm_start, vma->vm_end);
+
+                                if (!in_atomic)
                                         mmput(mm);
+
                                 goto done;
                         }
 
                         vml = vml->next;
                 }
-                if (!in_exception)
+                if (!in_atomic)
                         mmput(mm);
         }
 
@@ -506,7 +521,7 @@ asmlinkage void trap_c(struct pt_regs *fp)
 
         info.si_signo = sig;
         info.si_errno = 0;
-        info.si_addr = (void *)fp->pc;
+        info.si_addr = (void __user *)fp->pc;
         force_sig_info(sig, &info, current);
 
         trace_buffer_restore(j);
@@ -655,21 +670,31 @@ void dump_bfin_process(struct pt_regs *fp)
         else if (context & 0x8000)
                 printk(KERN_NOTICE "Kernel process context\n");
 
-        if (current->pid && current->mm) {
+        /* Because we are crashing, and pointers could be bad, we check things
+         * pretty closely before we use them
+         */
+        if ((unsigned long)current >= FIXED_CODE_START &&
+            !((unsigned long)current & 0x3) && current->pid) {
                 printk(KERN_NOTICE "CURRENT PROCESS:\n");
-                printk(KERN_NOTICE "COMM=%s PID=%d\n",
-                        current->comm, current->pid);
-
-                printk(KERN_NOTICE "TEXT = 0x%p-0x%p  DATA = 0x%p-0x%p\n"
-                        KERN_NOTICE "BSS = 0x%p-0x%p   USER-STACK = 0x%p\n"
-                        KERN_NOTICE "\n",
-                        (void *)current->mm->start_code,
-                        (void *)current->mm->end_code,
-                        (void *)current->mm->start_data,
-                        (void *)current->mm->end_data,
-                        (void *)current->mm->end_data,
-                        (void *)current->mm->brk,
-                        (void *)current->mm->start_stack);
+                if (current->comm >= (char *)FIXED_CODE_START)
+                        printk(KERN_NOTICE "COMM=%s PID=%d\n",
+                                current->comm, current->pid);
+                else
+                        printk(KERN_NOTICE "COMM= invalid\n");
+
+                if (!((unsigned long)current->mm & 0x3) && (unsigned long)current->mm >= FIXED_CODE_START)
+                        printk(KERN_NOTICE  "TEXT = 0x%p-0x%p        DATA = 0x%p-0x%p\n"
+                                KERN_NOTICE " BSS = 0x%p-0x%p  USER-STACK = 0x%p\n"
+                                KERN_NOTICE "\n",
+                                (void *)current->mm->start_code,
+                                (void *)current->mm->end_code,
+                                (void *)current->mm->start_data,
+                                (void *)current->mm->end_data,
+                                (void *)current->mm->end_data,
+                                (void *)current->mm->brk,
+                                (void *)current->mm->start_stack);
+                else
+                        printk(KERN_NOTICE "invalid mm\n");
         } else
                 printk(KERN_NOTICE "\n" KERN_NOTICE
                      "No Valid process in current context\n");
@@ -680,10 +705,7 @@ void dump_bfin_mem(struct pt_regs *fp)
         unsigned short *addr, *erraddr, val = 0, err = 0;
         char sti = 0, buf[6];
 
-        if (unlikely((fp->seqstat & SEQSTAT_EXCAUSE) == VEC_HWERR))
-                erraddr = (void *)fp->pc;
-        else
-                erraddr = (void *)fp->retx;
+        erraddr = (void *)fp->pc;
 
         printk(KERN_NOTICE "return address: [0x%p]; contents of:", erraddr);
 
@@ -807,9 +829,9 @@ unlock:
 
         if (((long)fp->seqstat &  SEQSTAT_EXCAUSE) &&
             (((long)fp->seqstat & SEQSTAT_EXCAUSE) != VEC_HWERR)) {
-                decode_address(buf, bfin_read_DCPLB_FAULT_ADDR());
+                decode_address(buf, saved_dcplb_fault_addr);
                 printk(KERN_NOTICE "DCPLB_FAULT_ADDR: %s\n", buf);
-                decode_address(buf, bfin_read_ICPLB_FAULT_ADDR());
+                decode_address(buf, saved_icplb_fault_addr);
                 printk(KERN_NOTICE "ICPLB_FAULT_ADDR: %s\n", buf);
         }
 
@@ -917,8 +939,8 @@ void panic_cplb_error(int cplb_panic, struct pt_regs *fp)
 
         oops_in_progress = 1;
 
-        printk(KERN_EMERG "DCPLB_FAULT_ADDR=%p\n", (void *)bfin_read_DCPLB_FAULT_ADDR());
-        printk(KERN_EMERG "ICPLB_FAULT_ADDR=%p\n", (void *)bfin_read_ICPLB_FAULT_ADDR());
+        printk(KERN_EMERG "DCPLB_FAULT_ADDR=%p\n", saved_dcplb_fault_addr);
+        printk(KERN_EMERG "ICPLB_FAULT_ADDR=%p\n", saved_icplb_fault_addr);
         dump_bfin_process(fp);
         dump_bfin_mem(fp);
         show_regs(fp);