+/* rdar://problem/21244753 */
+uint32_t
+PE_i_can_has_debugger(uint32_t *debug_flags)
+{
+#if DEVELOPMENT || DEBUG
+ if (debug_flags) {
+ assert(debug_boot_arg_inited);
+ }
+#endif
+
+#if CONFIG_CSR
+ if (csr_check(CSR_ALLOW_KERNEL_DEBUGGER) != 0) {
+ if (debug_flags)
+ *debug_flags = 0;
+ return FALSE;
+ }
+#endif
+ if (debug_flags) {
+ *debug_flags = debug_boot_arg;
+ }
+ return TRUE;
+}
+
+uint32_t
+PE_get_offset_into_panic_region(char *location)
+{
+ assert(panic_info != NULL);
+ assert(location > (char *) panic_info);
+
+ return (uint32_t) (location - (char *) panic_info);
+}
+
+void
+PE_init_panicheader()
+{
+ bzero(panic_info, offsetof(struct macos_panic_header, mph_data));
+ panic_info->mph_panic_log_offset = PE_get_offset_into_panic_region(debug_buf_base);
+
+ panic_info->mph_magic = MACOS_PANIC_MAGIC;
+ panic_info->mph_version = MACOS_PANIC_HEADER_CURRENT_VERSION;
+
+ return;
+}
+
+/*
+ * Tries to update the panic header to keep it consistent on nested panics.
+ *
+ * NOTE: The purpose of this function is NOT to detect/correct corruption in the panic region,
+ * it is to update the panic header to make it consistent when we nest panics.
+ *
+ * We try to avoid nested panics/asserts on x86 because they are difficult to debug, so log any
+ * inconsistencies we find.
+ */
+void
+PE_update_panicheader_nestedpanic()
+{
+ /* If the panic log offset is not set, re-init the panic header */
+ if (panic_info->mph_panic_log_offset == 0) {
+ PE_init_panicheader();
+ panic_info->mph_panic_flags |= MACOS_PANIC_HEADER_FLAG_NESTED_PANIC;
+ return;
+ }
+
+ panic_info->mph_panic_flags |= MACOS_PANIC_HEADER_FLAG_NESTED_PANIC;
+
+ /* Usually indicative of corruption in the panic region */
+ if(!(((panic_info->mph_stackshot_offset == 0) && (panic_info->mph_stackshot_len == 0)) ||
+ ((panic_info->mph_stackshot_offset != 0) && (panic_info->mph_stackshot_len != 0)))) {
+ kdb_printf("panic_info contains invalid stackshot metadata: mph_stackshot_offset 0x%x mph_stackshot_len 0x%x\n",
+ panic_info->mph_stackshot_offset, panic_info->mph_stackshot_len);
+ }
+
+ /*
+ * macOS panic logs contain nested panic data, if we've already closed the panic log,
+ * begin the other log.
+ */
+ if ((panic_info->mph_panic_log_len != 0) && (panic_info->mph_other_log_offset == 0)) {
+ panic_info->mph_other_log_offset = PE_get_offset_into_panic_region(debug_buf_ptr);
+
+ /* Usually indicative of corruption in the panic region */
+ if (panic_info->mph_other_log_len != 0) {
+ kdb_printf("panic_info contains invalid other log metadata (zero offset but non-zero length), length was 0x%x, zeroing value\n",
+ panic_info->mph_other_log_len);
+ panic_info->mph_other_log_len = 0;
+ }
+ }
+
+ return;
+}
projects / apple / xnu.git / blobdiff