Blackfin arch: Add unwinding for stack info, and a little more detail on trace buffer
Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
diff --git a/arch/blackfin/kernel/traps.c b/arch/blackfin/kernel/traps.c
index f061f51..ad922ab 100644
--- a/arch/blackfin/kernel/traps.c
+++ b/arch/blackfin/kernel/traps.c
@@ -69,8 +69,6 @@
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 @@
if (!in_atomic)
mmput(mm);
+ if (!strlen(buf))
+ sprintf(buf, "<0x%p> [ %s ] dynamic memory", (void *)address, name);
+
goto done;
}
@@ -173,7 +174,7 @@
}
/* 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 @@
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 @@
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 @@
#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 @@
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 @@
}
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");
+ if (!get_instruction(&opcode, ins_addr))
+ return false;
- 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 ((opcode >= 0x0060 && opcode <= 0x0067) ||
+ (opcode >= 0x0070 && opcode <= 0x0077))
+ return true;
- printk(KERN_NOTICE "\n");
+ 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;
+
+ /*
+ * 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
+ */
+
+ /* 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");
}
- addr = (unsigned long)stack;
- endstack = (unsigned long *)PAGE_ALIGN(addr);
-
- 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++);
- }
- printk("\n");
-
- show_trace(task, stack);
}
void dump_stack(void)
@@ -715,19 +911,9 @@
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);
