[v5,1/2] APEI: Add support to notify the vendor specific HW errors

diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
index 24c9642e8fc7..d83f0b1aad0d 100644
--- a/drivers/acpi/apei/ghes.c
+++ b/drivers/acpi/apei/ghes.c
@@ -490,6 +490,32 @@  static void ghes_handle_aer(struct 
acpi_hest_generic_data *gdata)
  #endif
  }

+static ATOMIC_NOTIFIER_HEAD(ghes_event_notify_list);
+
+/**
+ * ghes_register_event_notifier - register an event notifier
+ * for the non-fatal HW errors.
+ * @nb: pointer to the notifier_block structure of the event handler.
+ *
+ * return 0 : SUCCESS, non-zero : FAIL
+ */
+int ghes_register_event_notifier(struct notifier_block *nb)
+{
+	return atomic_notifier_chain_register(&ghes_event_notify_list, nb);
+}
+EXPORT_SYMBOL_GPL(ghes_register_event_notifier);
+
+/**
+ * ghes_unregister_event_notifier - unregister the previously
+ * registered event notifier.
+ * @nb: pointer to the notifier_block structure of the event handler.
+ */
+void ghes_unregister_event_notifier(struct notifier_block *nb)
+{
+	atomic_notifier_chain_unregister(&ghes_event_notify_list, nb);
+}
+EXPORT_SYMBOL_GPL(ghes_unregister_event_notifier);
+
  static void ghes_do_proc(struct ghes *ghes,
  			 const struct acpi_hest_generic_status *estatus)
  {
@@ -526,10 +552,17 @@  static void ghes_do_proc(struct ghes *ghes,
  			log_arm_hw_error(err);
  		} else {
  			void *err = acpi_hest_get_payload(gdata);
+			u8 error_handled = false;
+			int ret;
+
+			ret = atomic_notifier_call_chain(&ghes_event_notify_list, 0, gdata);
+			if (ret & NOTIFY_OK)
+				error_handled = true;

  			log_non_standard_event(sec_type, fru_id, fru_text,
  					       sec_sev, err,
-					       gdata->error_data_length);
+					       gdata->error_data_length,
+					       error_handled);
  		}
  	}
  }
diff --git a/drivers/ras/ras.c b/drivers/ras/ras.c
index 95540ea8dd9d..0ed784a8466e 100644
--- a/drivers/ras/ras.c
+++ b/drivers/ras/ras.c
@@ -16,9 +16,10 @@ 

  void log_non_standard_event(const guid_t *sec_type, const guid_t *fru_id,
  			    const char *fru_text, const u8 sev, const u8 *err,
-			    const u32 len)
+			    const u32 len, const u8 error_handled)
  {
-	trace_non_standard_event(sec_type, fru_id, fru_text, sev, err, len);
+	trace_non_standard_event(sec_type, fru_id, fru_text, sev,
+				 err, len, error_handled);
  }

  void log_arm_hw_error(struct cper_sec_proc_arm *err)
diff --git a/include/acpi/ghes.h b/include/acpi/ghes.h
index e3f1cddb4ac8..a3dd82069069 100644
--- a/include/acpi/ghes.h
+++ b/include/acpi/ghes.h
@@ -50,6 +50,34 @@  enum {
  	GHES_SEV_PANIC = 0x3,
  };

+
+#ifdef CONFIG_ACPI_APEI_GHES
+/**
+ * ghes_register_event_notifier - register an event notifier
+ * for the non-fatal HW errors.
+ * @nb: pointer to the notifier_block structure of the event notifier.
+ *
+ * Return : 0 - SUCCESS, non-zero - FAIL.
+ */
+int ghes_register_event_notifier(struct notifier_block *nb);
+
+/**
+ * ghes_unregister_event_notifier - unregister the previously
+ * registered event notifier.
+ * @nb: pointer to the notifier_block structure of the event notifier.
+ */
+void ghes_unregister_event_notifier(struct notifier_block *nb);
+#else
+static inline int ghes_register_event_notifier(struct notifier_block *nb)
+{
+	return -ENODEV;
+}
+
+static inline void ghes_unregister_event_notifier(struct notifier_block 
*nb)
+{
+}
+#endif
+
  int ghes_estatus_pool_init(int num_ghes);

  /* From drivers/edac/ghes_edac.c */
diff --git a/include/linux/ras.h b/include/linux/ras.h
index 7c3debb47c87..6ed3c67ab905 100644
--- a/include/linux/ras.h
+++ b/include/linux/ras.h
@@ -28,13 +28,15 @@  static inline int cec_add_elem(u64 pfn)		{ return 
-ENODEV; }
  #ifdef CONFIG_RAS
  void log_non_standard_event(const guid_t *sec_type,
  			    const guid_t *fru_id, const char *fru_text,
-			    const u8 sev, const u8 *err, const u32 len);
+			    const u8 sev, const u8 *err, const u32 len,
+			    const u8 error_handled);
  void log_arm_hw_error(struct cper_sec_proc_arm *err);
  #else
  static inline void
  log_non_standard_event(const guid_t *sec_type,
  		       const guid_t *fru_id, const char *fru_text,
-		       const u8 sev, const u8 *err, const u32 len)
+		       const u8 sev, const u8 *err, const u32 len,
+		       const u8 error_handled);
  { return; }
  static inline void
  log_arm_hw_error(struct cper_sec_proc_arm *err) { return; }
diff --git a/include/ras/ras_event.h b/include/ras/ras_event.h
index 36c5c5e38c1d..38fd05d82d8e 100644
--- a/include/ras/ras_event.h
+++ b/include/ras/ras_event.h
@@ -223,9 +223,10 @@  TRACE_EVENT(non_standard_event,
  		 const char *fru_text,
  		 const u8 sev,
  		 const u8 *err,
-		 const u32 len),
+		 const u32 len,
+		 const u8 error_handled),

-	TP_ARGS(sec_type, fru_id, fru_text, sev, err, len),
+	TP_ARGS(sec_type, fru_id, fru_text, sev, err, len, error_handled),

  	TP_STRUCT__entry(
  		__array(char, sec_type, UUID_SIZE)
@@ -234,6 +235,7 @@  TRACE_EVENT(non_standard_event,
  		__field(u8, sev)
  		__field(u32, len)
  		__dynamic_array(u8, buf, len)
+		__field(u8, error_handled)
  	),

  	TP_fast_assign(
@@ -243,6 +245,7 @@  TRACE_EVENT(non_standard_event,
  		__entry->sev = sev;
  		__entry->len = len;
  		memcpy(__get_dynamic_array(buf), err, len);
+		__entry->error_handled = error_handled;
  	),

  	TP_printk("severity: %d; sec type:%pU; FRU: %pU %s; data len:%d; raw