RE: [PATCH v11 1/2] ACPI / APEI: Add a notifier chain for unknown (vendor) CPER records

[Shiju Jose <shiju.jose@huawei.com>]

Hi Rafael, Hi James,

Can you help to merge this patch because I added and tested all the suggestions from James.

Thanks,
Shiju

>-----Original Message-----
>From: linux-pci-owner@vger.kernel.org [mailto:linux-pci-
>owner@vger.kernel.org] On Behalf Of Shiju Jose
>Sent: 22 June 2020 13:05
>To: linux-acpi@vger.kernel.org; linux-pci@vger.kernel.org; linux-
>kernel@vger.kernel.org; rjw@rjwysocki.net; helgaas@kernel.org;
>bp@alien8.de; james.morse@arm.com; lenb@kernel.org;
>tony.luck@intel.com; dan.carpenter@oracle.com;
>zhangliguang@linux.alibaba.com; andriy.shevchenko@linux.intel.com;
>Wangkefeng (OS Kernel Lab) <wangkefeng.wang@huawei.com>;
>jroedel@suse.de
>Cc: Linuxarm <linuxarm@huawei.com>; yangyicong
><yangyicong@huawei.com>; Jonathan Cameron
><jonathan.cameron@huawei.com>; tanxiaofei <tanxiaofei@huawei.com>
>Subject: [PATCH v11 1/2] ACPI / APEI: Add a notifier chain for unknown
>(vendor) CPER records
>
>CPER records describing a firmware-first error are identified by GUID.
>The ghes driver currently logs, but ignores any unknown CPER records.
>This prevents describing errors that can't be represented by a standard entry,
>that would otherwise allow a driver to recover from an error.
>The UEFI spec calls these 'Non-standard Section Body' (N.2.3 of version 2.8).
>
>Add a notifier chain for these non-standard/vendor-records. Callers must
>identify their type of records by GUID.
>
>Record data is copied to memory from the ghes_estatus_pool to allow us to
>keep it until after the notifier has run.
>
>Signed-off-by: Shiju Jose <shiju.jose@huawei.com> [ Removed kfifo and
>ghes_gdata_pool. Expanded commit message ]
>Signed-off-by: James Morse <james.morse@arm.com>
>---
> drivers/acpi/apei/ghes.c | 63
>++++++++++++++++++++++++++++++++++++++++
> include/acpi/ghes.h      | 27 +++++++++++++++++
> 2 files changed, 90 insertions(+)
>
>diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c index
>81bf71b10d44..99df00f64306 100644
>--- a/drivers/acpi/apei/ghes.c
>+++ b/drivers/acpi/apei/ghes.c
>@@ -79,6 +79,12 @@
> 	((struct acpi_hest_generic_status *)				\
> 	 ((struct ghes_estatus_node *)(estatus_node) + 1))
>
>+#define GHES_VENDOR_ENTRY_LEN(gdata_len)                               \
>+	(sizeof(struct ghes_vendor_record_entry) + (gdata_len))
>+#define GHES_GDATA_FROM_VENDOR_ENTRY(vendor_entry)                     \
>+	((struct acpi_hest_generic_data *)                              \
>+	((struct ghes_vendor_record_entry *)(vendor_entry) + 1))
>+
> /*
>  *  NMI-like notifications vary by architecture, before the compiler can prune
>  *  unused static functions it needs a value for these enums.
>@@ -123,6 +129,12 @@ static DEFINE_MUTEX(ghes_list_mutex);
>  */
> static DEFINE_SPINLOCK(ghes_notify_lock_irq);
>
>+struct ghes_vendor_record_entry {
>+	struct work_struct work;
>+	int error_severity;
>+	char vendor_record[];
>+};
>+
> static struct gen_pool *ghes_estatus_pool;  static unsigned long
>ghes_estatus_pool_size_request;
>
>@@ -511,6 +523,56 @@ static void ghes_handle_aer(struct
>acpi_hest_generic_data *gdata)  #endif  }
>
>+static BLOCKING_NOTIFIER_HEAD(vendor_record_notify_list);
>+
>+int ghes_register_vendor_record_notifier(struct notifier_block *nb) {
>+	return blocking_notifier_chain_register(&vendor_record_notify_list,
>+nb); } EXPORT_SYMBOL_GPL(ghes_register_vendor_record_notifier);
>+
>+void ghes_unregister_vendor_record_notifier(struct notifier_block *nb)
>+{
>+	blocking_notifier_chain_unregister(&vendor_record_notify_list, nb);
>}
>+EXPORT_SYMBOL_GPL(ghes_unregister_vendor_record_notifier);
>+
>+static void ghes_vendor_record_work_func(struct work_struct *work) {
>+	struct ghes_vendor_record_entry *entry;
>+	struct acpi_hest_generic_data *gdata;
>+	u32 len;
>+
>+	entry = container_of(work, struct ghes_vendor_record_entry, work);
>+	gdata = GHES_GDATA_FROM_VENDOR_ENTRY(entry);
>+
>+	blocking_notifier_call_chain(&vendor_record_notify_list,
>+				     entry->error_severity, gdata);
>+
>+	len = GHES_VENDOR_ENTRY_LEN(acpi_hest_get_record_size(gdata));
>+	gen_pool_free(ghes_estatus_pool, (unsigned long)entry, len); }
>+
>+static void ghes_defer_non_standard_event(struct acpi_hest_generic_data
>*gdata,
>+					  int sev)
>+{
>+	struct acpi_hest_generic_data *copied_gdata;
>+	struct ghes_vendor_record_entry *entry;
>+	u32 len;
>+
>+	len = GHES_VENDOR_ENTRY_LEN(acpi_hest_get_record_size(gdata));
>+	entry = (void *)gen_pool_alloc(ghes_estatus_pool, len);
>+	if (!entry)
>+		return;
>+
>+	copied_gdata = GHES_GDATA_FROM_VENDOR_ENTRY(entry);
>+	memcpy(copied_gdata, gdata, acpi_hest_get_record_size(gdata));
>+	entry->error_severity = sev;
>+
>+	INIT_WORK(&entry->work, ghes_vendor_record_work_func);
>+	schedule_work(&entry->work);
>+}
>+
> static bool ghes_do_proc(struct ghes *ghes,
> 			 const struct acpi_hest_generic_status *estatus)  {
>@@ -549,6 +611,7 @@ static bool ghes_do_proc(struct ghes *ghes,
> 		} else {
> 			void *err = acpi_hest_get_payload(gdata);
>
>+			ghes_defer_non_standard_event(gdata, sev);
> 			log_non_standard_event(sec_type, fru_id, fru_text,
> 					       sec_sev, err,
> 					       gdata->error_data_length);
>diff --git a/include/acpi/ghes.h b/include/acpi/ghes.h index
>517a5231cc1b..ae0e8847fdd5 100644
>--- a/include/acpi/ghes.h
>+++ b/include/acpi/ghes.h
>@@ -53,6 +53,33 @@ enum {
> 	GHES_SEV_PANIC = 0x3,
> };
>
>+#ifdef CONFIG_ACPI_APEI_GHES
>+/**
>+ * ghes_register_vendor_record_notifier - register a notifier for
>+vendor
>+ * records that the kernel would otherwise ignore.
>+ * @nb: pointer to the notifier_block structure of the event handler.
>+ *
>+ * return 0 : SUCCESS, non-zero : FAIL
>+ */
>+int ghes_register_vendor_record_notifier(struct notifier_block *nb);
>+
>+/**
>+ * ghes_unregister_vendor_record_notifier - unregister the previously
>+ * registered vendor record notifier.
>+ * @nb: pointer to the notifier_block structure of the vendor record
>handler.
>+ */
>+void ghes_unregister_vendor_record_notifier(struct notifier_block *nb);
>+#else static inline int ghes_register_vendor_record_notifier(struct
>+notifier_block *nb) {
>+	return -ENODEV;
>+}
>+
>+static inline void ghes_unregister_vendor_record_notifier(struct
>+notifier_block *nb) { } #endif
>+
> int ghes_estatus_pool_init(int num_ghes);
>
> /* From drivers/edac/ghes_edac.c */
>--
>2.17.1
>