- kprobe_opcode_t *scan_start = addr - 1;
- kprobe_opcode_t *scan_end = addr - MAX_ATOMIC_CONTEXT_SIZE;
-#if defined(CONFIG_MODULES) && defined(MODULES_VADDR)
- struct module *mod;
-#endif
-
- if (addr >= (kprobe_opcode_t *)_text &&
- scan_end < (kprobe_opcode_t *)_text)
- scan_end = (kprobe_opcode_t *)_text;
-#if defined(CONFIG_MODULES) && defined(MODULES_VADDR)
- else {
- preempt_disable();
- mod = __module_address((unsigned long)addr);
- if (mod && within_module_init((unsigned long)addr, mod) &&
- !within_module_init((unsigned long)scan_end, mod))
- scan_end = (kprobe_opcode_t *)mod->init_layout.base;
- else if (mod && within_module_core((unsigned long)addr, mod) &&
- !within_module_core((unsigned long)scan_end, mod))
- scan_end = (kprobe_opcode_t *)mod->core_layout.base;
- preempt_enable();
+ kprobe_opcode_t *scan_end = NULL;
+ unsigned long size = 0, offset = 0;
+
+ /*
+ * If there's a symbol defined in front of and near enough to
+ * the probe address assume it is the entry point to this
+ * code and use it to further limit how far back we search
+ * when determining if we're in an atomic sequence. If we could
+ * not find any symbol skip the atomic test altogether as we
+ * could otherwise end up searching irrelevant text/literals.
+ * KPROBES depends on KALLSYMS so this last case should never
+ * happen.
+ */
+ if (kallsyms_lookup_size_offset((unsigned long) addr, &size, &offset)) {
+ if (offset < (MAX_ATOMIC_CONTEXT_SIZE*sizeof(kprobe_opcode_t)))
+ scan_end = addr - (offset / sizeof(kprobe_opcode_t));
+ else
+ scan_end = addr - MAX_ATOMIC_CONTEXT_SIZE;