*/
#include <linux/sched.h>
#include <linux/stacktrace.h>
+#include <linux/module.h>
+#include <asm/stacktrace.h>
-#include <asm/smp.h>
-
-static inline int
-in_range(unsigned long start, unsigned long addr, unsigned long end)
+static void save_stack_warning(void *data, char *msg)
{
- return addr >= start && addr <= end;
}
-static unsigned long
-get_stack_end(struct task_struct *task, unsigned long stack)
+static void
+save_stack_warning_symbol(void *data, char *msg, unsigned long symbol)
{
- unsigned long stack_start, stack_end, flags;
- int i, cpu;
-
- /*
- * The most common case is that we are in the task stack:
- */
- stack_start = (unsigned long)task->thread_info;
- stack_end = stack_start + THREAD_SIZE;
-
- if (in_range(stack_start, stack, stack_end))
- return stack_end;
-
- /*
- * We are in an interrupt if irqstackptr is set:
- */
- raw_local_irq_save(flags);
- cpu = safe_smp_processor_id();
- stack_end = (unsigned long)cpu_pda(cpu)->irqstackptr;
-
- if (stack_end) {
- stack_start = stack_end & ~(IRQSTACKSIZE-1);
- if (in_range(stack_start, stack, stack_end))
- goto out_restore;
- /*
- * We get here if we are in an IRQ context but we
- * are also in an exception stack.
- */
- }
-
- /*
- * Iterate over all exception stacks, and figure out whether
- * 'stack' is in one of them:
- */
- for (i = 0; i < N_EXCEPTION_STACKS; i++) {
- /*
- * set 'end' to the end of the exception stack.
- */
- stack_end = per_cpu(init_tss, cpu).ist[i];
- stack_start = stack_end - EXCEPTION_STKSZ;
-
- /*
- * Is 'stack' above this exception frame's end?
- * If yes then skip to the next frame.
- */
- if (stack >= stack_end)
- continue;
- /*
- * Is 'stack' above this exception frame's start address?
- * If yes then we found the right frame.
- */
- if (stack >= stack_start)
- goto out_restore;
-
- /*
- * If this is a debug stack, and if it has a larger size than
- * the usual exception stacks, then 'stack' might still
- * be within the lower portion of the debug stack:
- */
-#if DEBUG_STKSZ > EXCEPTION_STKSZ
- if (i == DEBUG_STACK - 1 && stack >= stack_end - DEBUG_STKSZ) {
- /*
- * Black magic. A large debug stack is composed of
- * multiple exception stack entries, which we
- * iterate through now. Dont look:
- */
- do {
- stack_end -= EXCEPTION_STKSZ;
- stack_start -= EXCEPTION_STKSZ;
- } while (stack < stack_start);
-
- goto out_restore;
- }
-#endif
- }
- /*
- * Ok, 'stack' is not pointing to any of the system stacks.
- */
- stack_end = 0;
-
-out_restore:
- raw_local_irq_restore(flags);
-
- return stack_end;
}
-
-/*
- * Save stack-backtrace addresses into a stack_trace buffer:
- */
-static inline unsigned long
-save_context_stack(struct stack_trace *trace, unsigned int skip,
- unsigned long stack, unsigned long stack_end)
+static int save_stack_stack(void *data, char *name)
{
- unsigned long addr;
-
-#ifdef CONFIG_FRAME_POINTER
- unsigned long prev_stack = 0;
+ return -1;
+}
- while (in_range(prev_stack, stack, stack_end)) {
- pr_debug("stack: %p\n", (void *)stack);
- addr = (unsigned long)(((unsigned long *)stack)[1]);
- pr_debug("addr: %p\n", (void *)addr);
- if (!skip)
- trace->entries[trace->nr_entries++] = addr-1;
- else
- skip--;
- if (trace->nr_entries >= trace->max_entries)
- break;
- if (!addr)
- return 0;
- /*
- * Stack frames must go forwards (otherwise a loop could
- * happen if the stackframe is corrupted), so we move
- * prev_stack forwards:
- */
- prev_stack = stack;
- stack = (unsigned long)(((unsigned long *)stack)[0]);
- }
- pr_debug("invalid: %p\n", (void *)stack);
-#else
- while (stack < stack_end) {
- addr = ((unsigned long *)stack)[0];
- stack += sizeof(long);
- if (__kernel_text_address(addr)) {
- if (!skip)
- trace->entries[trace->nr_entries++] = addr-1;
- else
- skip--;
- if (trace->nr_entries >= trace->max_entries)
- break;
- }
+static void save_stack_address(void *data, unsigned long addr)
+{
+ struct stack_trace *trace = (struct stack_trace *)data;
+ if (trace->skip > 0) {
+ trace->skip--;
+ return;
}
-#endif
- return stack;
+ if (trace->nr_entries < trace->max_entries)
+ trace->entries[trace->nr_entries++] = addr;
}
-#define MAX_STACKS 10
+static struct stacktrace_ops save_stack_ops = {
+ .warning = save_stack_warning,
+ .warning_symbol = save_stack_warning_symbol,
+ .stack = save_stack_stack,
+ .address = save_stack_address,
+};
/*
* Save stack-backtrace addresses into a stack_trace buffer.
- * If all_contexts is set, all contexts (hardirq, softirq and process)
- * are saved. If not set then only the current context is saved.
*/
-void save_stack_trace(struct stack_trace *trace,
- struct task_struct *task, int all_contexts,
- unsigned int skip)
+void save_stack_trace(struct stack_trace *trace)
{
- unsigned long stack = (unsigned long)&stack;
- int i, nr_stacks = 0, stacks_done[MAX_STACKS];
-
- WARN_ON(trace->nr_entries || !trace->max_entries);
-
- if (!task)
- task = current;
-
- pr_debug("task: %p, ti: %p\n", task, task->thread_info);
-
- if (!task || task == current) {
- /* Grab rbp right from our regs: */
- asm ("mov %%rbp, %0" : "=r" (stack));
- pr_debug("rbp: %p\n", (void *)stack);
- } else {
- /* rbp is the last reg pushed by switch_to(): */
- stack = task->thread.rsp;
- pr_debug("other task rsp: %p\n", (void *)stack);
- stack = (unsigned long)(((unsigned long *)stack)[0]);
- pr_debug("other task rbp: %p\n", (void *)stack);
- }
-
- while (1) {
- unsigned long stack_end = get_stack_end(task, stack);
-
- pr_debug("stack: %p\n", (void *)stack);
- pr_debug("stack end: %p\n", (void *)stack_end);
-
- /*
- * Invalid stack addres?
- */
- if (!stack_end)
- return;
- /*
- * Were we in this stack already? (recursion)
- */
- for (i = 0; i < nr_stacks; i++)
- if (stacks_done[i] == stack_end)
- return;
- stacks_done[nr_stacks] = stack_end;
-
- stack = save_context_stack(trace, skip, stack, stack_end);
- if (!all_contexts || !stack ||
- trace->nr_entries >= trace->max_entries)
- return;
+ dump_trace(current, NULL, NULL, &save_stack_ops, trace);
+ if (trace->nr_entries < trace->max_entries)
trace->entries[trace->nr_entries++] = ULONG_MAX;
- if (trace->nr_entries >= trace->max_entries)
- return;
- if (++nr_stacks >= MAX_STACKS)
- return;
- }
}
-
+EXPORT_SYMBOL(save_stack_trace);
projects / powerpc.git / blobdiff