]> pilppa.com Git - linux-2.6-omap-h63xx.git/commitdiff
Blackfin arch: Add unwinding for stack info, and a little more detail on trace buffer
authorRobin Getz <rgetz@blackfin.uclinux.org>
Sat, 26 Jul 2008 11:45:46 +0000 (19:45 +0800)
committerBryan Wu <cooloney@kernel.org>
Sat, 26 Jul 2008 11:45:46 +0000 (19:45 +0800)
Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
arch/blackfin/kernel/traps.c

index f061f5181623e4214e6e606642c83a79c15ae1fc..ad922ab915438ef3d66820809285e1f9a8477deb 100644 (file)
@@ -69,8 +69,6 @@ void __init trap_init(void)
 
 unsigned long saved_icplb_fault_addr, saved_dcplb_fault_addr;
 
-int kstack_depth_to_print = 48;
-
 static void decode_address(char *buf, unsigned long address)
 {
        struct vm_list_struct *vml;
@@ -163,6 +161,9 @@ static void decode_address(char *buf, unsigned long address)
                                if (!in_atomic)
                                        mmput(mm);
 
+                               if (!strlen(buf))
+                                       sprintf(buf, "<0x%p> [ %s ] dynamic memory", (void *)address, name);
+
                                goto done;
                        }
 
@@ -173,7 +174,7 @@ static void decode_address(char *buf, unsigned long address)
        }
 
        /* we were unable to find this address anywhere */
-       sprintf(buf, "<0x%p> /* unknown address */", (void *)address);
+       sprintf(buf, "<0x%p> /* kernel dynamic memory */", (void *)address);
 
 done:
        write_unlock_irqrestore(&tasklist_lock, flags);
@@ -494,7 +495,7 @@ asmlinkage void trap_c(struct pt_regs *fp)
        BUG_ON(sig == 0);
 
        if (sig != SIGTRAP) {
-               unsigned long stack;
+               unsigned long *stack;
                dump_bfin_process(fp);
                dump_bfin_mem(fp);
                show_regs(fp);
@@ -508,14 +509,23 @@ asmlinkage void trap_c(struct pt_regs *fp)
                else
 #endif
                        dump_bfin_trace_buffer();
-               show_stack(current, &stack);
+
                if (oops_in_progress) {
+                       /* Dump the current kernel stack */
+                       printk(KERN_NOTICE "\n" KERN_NOTICE "Kernel Stack\n");
+                       show_stack(current, NULL);
+
                        print_modules();
 #ifndef CONFIG_ACCESS_CHECK
                        printk(KERN_EMERG "Please turn on "
                               "CONFIG_ACCESS_CHECK\n");
 #endif
                        panic("Kernel exception");
+               } else {
+                       /* Dump the user space stack */
+                       stack = (unsigned long *)rdusp();
+                       printk(KERN_NOTICE "Userspace Stack\n");
+                       show_stack(NULL, stack);
                }
        }
 
@@ -532,11 +542,71 @@ asmlinkage void trap_c(struct pt_regs *fp)
 
 #define EXPAND_LEN ((1 << CONFIG_DEBUG_BFIN_HWTRACE_EXPAND_LEN) * 256 - 1)
 
+/*
+ * Similar to get_user, do some address checking, then dereference
+ * Return true on sucess, false on bad address
+ */
+bool get_instruction(unsigned short *val, unsigned short *address)
+{
+
+       unsigned long addr;
+
+       addr = (unsigned long)address;
+
+       /* Check for odd addresses */
+       if (addr & 0x1)
+               return false;
+
+       /* Check that things do not wrap around */
+       if (addr > (addr + 2))
+               return false;
+
+       /*
+        * Since we are in exception context, we need to do a little address checking
+        * We need to make sure we are only accessing valid memory, and
+        * we don't read something in the async space that can hang forever
+        */
+       if ((addr >= FIXED_CODE_START && (addr + 2) <= physical_mem_end) ||
+#ifdef L2_START
+           (addr >= L2_START && (addr + 2) <= (L2_START + L2_LENGTH)) ||
+#endif
+           (addr >= BOOT_ROM_START && (addr + 2) <= (BOOT_ROM_START + BOOT_ROM_LENGTH)) ||
+#if L1_DATA_A_LENGTH != 0
+           (addr >= L1_DATA_A_START && (addr + 2) <= (L1_DATA_A_START + L1_DATA_A_LENGTH)) ||
+#endif
+#if L1_DATA_B_LENGTH != 0
+           (addr >= L1_DATA_B_START && (addr + 2) <= (L1_DATA_B_START + L1_DATA_B_LENGTH)) ||
+#endif
+           (addr >= L1_SCRATCH_START && (addr + 2) <= (L1_SCRATCH_START + L1_SCRATCH_LENGTH)) ||
+           (!(bfin_read_EBIU_AMBCTL0() & B0RDYEN) &&
+              addr >= ASYNC_BANK0_BASE && (addr + 2) <= (ASYNC_BANK0_BASE + ASYNC_BANK0_SIZE)) ||
+           (!(bfin_read_EBIU_AMBCTL0() & B1RDYEN) &&
+              addr >= ASYNC_BANK1_BASE && (addr + 2) <= (ASYNC_BANK1_BASE + ASYNC_BANK1_SIZE)) ||
+           (!(bfin_read_EBIU_AMBCTL1() & B2RDYEN) &&
+              addr >= ASYNC_BANK2_BASE && (addr + 2) <= (ASYNC_BANK2_BASE + ASYNC_BANK1_SIZE)) ||
+           (!(bfin_read_EBIU_AMBCTL1() & B3RDYEN) &&
+             addr >= ASYNC_BANK3_BASE && (addr + 2) <= (ASYNC_BANK3_BASE + ASYNC_BANK1_SIZE))) {
+               *val = *address;
+               return true;
+       }
+
+#if L1_CODE_LENGTH != 0
+       if (addr >= L1_CODE_START && (addr + 2) <= (L1_CODE_START + L1_CODE_LENGTH)) {
+               dma_memcpy(val, address, 2);
+               return true;
+       }
+#endif
+
+
+       return false;
+}
+
 void dump_bfin_trace_buffer(void)
 {
 #ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON
        int tflags, i = 0;
        char buf[150];
+       unsigned short val = 0, *addr;
 #ifdef CONFIG_DEBUG_BFIN_HWTRACE_EXPAND
        int j, index;
 #endif
@@ -549,8 +619,42 @@ void dump_bfin_trace_buffer(void)
                for (; bfin_read_TBUFSTAT() & TBUFCNT; i++) {
                        decode_address(buf, (unsigned long)bfin_read_TBUF());
                        printk(KERN_NOTICE "%4i Target : %s\n", i, buf);
-                       decode_address(buf, (unsigned long)bfin_read_TBUF());
-                       printk(KERN_NOTICE "     Source : %s\n", buf);
+                       addr = (unsigned short *)bfin_read_TBUF();
+                       decode_address(buf, (unsigned long)addr);
+                       printk(KERN_NOTICE "     Source : %s ", buf);
+                       if (get_instruction(&val, addr)) {
+                               if (val == 0x0010)
+                                       printk("RTS");
+                               else if (val == 0x0011)
+                                       printk("RTI");
+                               else if (val == 0x0012)
+                                       printk("RTX");
+                               else if (val >= 0x0050 && val <= 0x0057)
+                                       printk("JUMP (P%i)", val & 7);
+                               else if (val >= 0x0060 && val <= 0x0067)
+                                       printk("CALL (P%i)", val & 7);
+                               else if (val >= 0x0070 && val <= 0x0077)
+                                       printk("CALL (PC+P%i)", val & 7);
+                               else if (val >= 0x0080 && val <= 0x0087)
+                                       printk("JUMP (PC+P%i)", val & 7);
+                               else if ((val >= 0x1000 && val <= 0x13FF) ||
+                                   (val >= 0x1800 && val <= 0x1BFF))
+                                       printk("IF !CC JUMP");
+                               else if ((val >= 0x1400 && val <= 0x17ff) ||
+                                   (val >= 0x1c00 && val <= 0x1fff))
+                                       printk("IF CC JUMP");
+                               else if (val >= 0x2000 && val <= 0x2fff)
+                                       printk("JUMP.S");
+                               else if (val >= 0xe080 && val <= 0xe0ff)
+                                       printk("LSETUP");
+                               else if (val >= 0xe200 && val <= 0xe2ff)
+                                       printk("JUMP.L");
+                               else if (val >= 0xe300 && val <= 0xe3ff)
+                                       printk("CALL pcrel");
+                               else
+                                       printk("0x%04x", val);
+                       }
+                       printk("\n");
                }
        }
 
@@ -582,59 +686,151 @@ void dump_bfin_trace_buffer(void)
 }
 EXPORT_SYMBOL(dump_bfin_trace_buffer);
 
-static void show_trace(struct task_struct *tsk, unsigned long *sp)
+/*
+ * Checks to see if the address pointed to is either a
+ * 16-bit CALL instruction, or a 32-bit CALL instruction
+ */
+bool is_bfin_call(unsigned short *addr)
 {
-       unsigned long addr;
+       unsigned short opcode = 0, *ins_addr;
+       ins_addr = (unsigned short *)addr;
 
-       printk(KERN_NOTICE "\n" KERN_NOTICE "Call Trace:\n");
-
-       while (!kstack_end(sp)) {
-               addr = *sp++;
-               /*
-                * If the address is either in the text segment of the
-                * kernel, or in the region which contains vmalloc'ed
-                * memory, it *may* be the address of a calling
-                * routine; if so, print it so that someone tracing
-                * down the cause of the crash will be able to figure
-                * out the call path that was taken.
-                */
-               if (kernel_text_address(addr))
-                       print_ip_sym(addr);
-       }
+       if (!get_instruction(&opcode, ins_addr))
+               return false;
 
-       printk(KERN_NOTICE "\n");
-}
+       if ((opcode >= 0x0060 && opcode <= 0x0067) ||
+           (opcode >= 0x0070 && opcode <= 0x0077))
+               return true;
+
+       ins_addr--;
+       if (!get_instruction(&opcode, ins_addr))
+               return false;
 
+       if (opcode >= 0xE300 && opcode <= 0xE3FF)
+               return true;
+
+       return false;
+
+}
 void show_stack(struct task_struct *task, unsigned long *stack)
 {
-       unsigned long *endstack, addr;
-       int i;
+       unsigned int *addr, *endstack, *fp = 0, *frame;
+       unsigned short *ins_addr;
+       char buf[150];
+       unsigned int i, j, ret_addr, frame_no = 0;
 
-       /* Cannot call dump_bfin_trace_buffer() here as show_stack() is
-        * called externally in some places in the kernel.
+       /*
+        * If we have been passed a specific stack, use that one otherwise
+        *    if we have been passed a task structure, use that, otherwise
+        *    use the stack of where the variable "stack" exists
         */
 
-       if (!stack) {
-               if (task)
+       if (stack == NULL) {
+               if (task) {
+                       /* We know this is a kernel stack, so this is the start/end */
                        stack = (unsigned long *)task->thread.ksp;
-               else
+                       endstack = (unsigned int *)(((unsigned int)(stack) & ~(THREAD_SIZE - 1)) + THREAD_SIZE);
+               } else {
+                       /* print out the existing stack info */
                        stack = (unsigned long *)&stack;
+                       endstack = (unsigned int *)PAGE_ALIGN((unsigned int)stack);
+               }
+       } else
+               endstack = (unsigned int *)PAGE_ALIGN((unsigned int)stack);
+
+       decode_address(buf, (unsigned int)stack);
+       printk(KERN_NOTICE "Stack info:\n" KERN_NOTICE " SP: [0x%p] %s\n", stack, buf);
+       addr = (unsigned int *)((unsigned int)stack & ~0x3F);
+
+       /* First thing is to look for a frame pointer */
+       for (addr = (unsigned int *)((unsigned int)stack & ~0xF), i = 0;
+               addr < endstack; addr++, i++) {
+               if (*addr & 0x1)
+                       continue;
+               ins_addr = (unsigned short *)*addr;
+               ins_addr--;
+               if (is_bfin_call(ins_addr))
+                       fp = addr - 1;
+
+               if (fp) {
+                       /* Let's check to see if it is a frame pointer */
+                       while (fp >= (addr - 1) && fp < endstack && fp)
+                               fp = (unsigned int *)*fp;
+                       if (fp == 0 || fp == endstack) {
+                               fp = addr - 1;
+                               break;
+                       }
+                       fp = 0;
+               }
        }
+       if (fp) {
+               frame = fp;
+               printk(" FP: (0x%p)\n", fp);
+       } else
+               frame = 0;
 
-       addr = (unsigned long)stack;
-       endstack = (unsigned long *)PAGE_ALIGN(addr);
+       /*
+        * Now that we think we know where things are, we
+        * walk the stack again, this time printing things out
+        * incase there is no frame pointer, we still look for
+        * valid return addresses
+        */
 
-       printk(KERN_NOTICE "Stack from %08lx:", (unsigned long)stack);
-       for (i = 0; i < kstack_depth_to_print; i++) {
-               if (stack + 1 > endstack)
-                       break;
-               if (i % 8 == 0)
-                       printk("\n" KERN_NOTICE "       ");
-               printk(" %08lx", *stack++);
+       /* First time print out data, next time, print out symbols */
+       for (j = 0; j <= 1; j++) {
+               if (j)
+                       printk(KERN_NOTICE "Return addresses in stack:\n");
+               else
+                       printk(KERN_NOTICE " Memory from 0x%08lx to %p", ((long unsigned int)stack & ~0xF), endstack);
+
+               fp = frame;
+               frame_no = 0;
+
+               for (addr = (unsigned int *)((unsigned int)stack & ~0xF), i = 0;
+                    addr <= endstack; addr++, i++) {
+
+                       ret_addr = 0;
+                       if (!j && i % 8 == 0)
+                               printk("\n" KERN_NOTICE "%p:",addr);
+
+                       /* if it is an odd address, or zero, just skip it */
+                       if (*addr & 0x1 || !*addr)
+                               goto print;
+
+                       ins_addr = (unsigned short *)*addr;
+
+                       /* Go back one instruction, and see if it is a CALL */
+                       ins_addr--;
+                       ret_addr = is_bfin_call(ins_addr);
+ print:
+                       if (!j && stack == (unsigned long *)addr)
+                               printk("[%08x]", *addr);
+                       else if (ret_addr)
+                               if (j) {
+                                       decode_address(buf, (unsigned int)*addr);
+                                       if (frame == addr) {
+                                               printk(KERN_NOTICE "   frame %2i : %s\n", frame_no, buf);
+                                               continue;
+                                       }
+                                       printk(KERN_NOTICE "    address : %s\n", buf);
+                               } else
+                                       printk("<%08x>", *addr);
+                       else if (fp == addr) {
+                               if (j)
+                                       frame = addr+1;
+                               else
+                                       printk("(%08x)", *addr);
+
+                               fp = (unsigned int *)*addr;
+                               frame_no++;
+
+                       } else if (!j)
+                               printk(" %08x ", *addr);
+               }
+               if (!j)
+                       printk("\n");
        }
-       printk("\n");
 
-       show_trace(task, stack);
 }
 
 void dump_stack(void)
@@ -715,19 +911,9 @@ void dump_bfin_mem(struct pt_regs *fp)
                if (!((unsigned long)addr & 0xF))
                        printk("\n" KERN_NOTICE "0x%p: ", addr);
 
-               if (get_user(val, addr)) {
-                       if (addr >= (unsigned short *)L1_CODE_START &&
-                           addr < (unsigned short *)(L1_CODE_START + L1_CODE_LENGTH)) {
-                               dma_memcpy(&val, addr, sizeof(val));
-                               sprintf(buf, "%04x", val);
-                       } else if (addr >= (unsigned short *)FIXED_CODE_START &&
-                               addr <= (unsigned short *)memory_start) {
-                               val = bfin_read16(addr);
-                               sprintf(buf, "%04x", val);
-                       } else {
+               if (get_instruction(&val, addr)) {
                                val = 0;
                                sprintf(buf, "????");
-                       }
                } else
                        sprintf(buf, "%04x", val);