[PATCH 3/3] EDAC, ghes: Make it a proper module
From: Borislav Petkov
Date: Wed Jul 26 2017 - 04:50:03 EST
From: Borislav Petkov <bp@xxxxxxx>
Register with the GHES notifier chain so that there's no need to call
into the module with ghes_edac_report_mem_error().
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
---
drivers/acpi/apei/ghes.c | 18 +++----
drivers/edac/Kconfig | 4 +-
drivers/edac/ghes_edac.c | 129 ++++++++++++++++++++++++-----------------------
include/acpi/ghes.h | 25 ---------
4 files changed, 74 insertions(+), 102 deletions(-)
diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
index 3f05f5ff3461..37cd698cacd2 100644
--- a/drivers/acpi/apei/ghes.c
+++ b/drivers/acpi/apei/ghes.c
@@ -475,11 +475,11 @@ static void ghes_handle_memory_failure(struct acpi_hest_generic_data *gdata, int
static void ghes_do_proc(struct ghes *ghes,
const struct acpi_hest_generic_status *estatus)
{
- int sev, sec_sev;
struct acpi_hest_generic_data *gdata;
guid_t *sec_type;
guid_t *fru_id = &NULL_UUID_LE;
char *fru_text = "";
+ int sev, sec_sev;
sev = ghes_severity(estatus->error_severity);
apei_estatus_for_each_section(estatus, gdata) {
@@ -494,7 +494,8 @@ static void ghes_do_proc(struct ghes *ghes,
if (guid_equal(sec_type, &CPER_SEC_PLATFORM_MEM)) {
struct cper_sec_mem_err *mem_err = acpi_hest_get_payload(gdata);
- ghes_edac_report_mem_error(ghes, sev, mem_err);
+
+ atomic_notifier_call_chain(&ghes_edac_chain, sev, &mem_err);
arch_apei_report_mem_error(sev, mem_err);
ghes_handle_memory_failure(gdata, sev);
@@ -1153,10 +1154,6 @@ static int ghes_probe(struct platform_device *ghes_dev)
goto err;
}
- rc = ghes_edac_register(ghes, &ghes_dev->dev);
- if (rc < 0)
- goto err;
-
switch (generic->notify.type) {
case ACPI_HEST_NOTIFY_POLLED:
setup_deferrable_timer(&ghes->timer, ghes_poll_func,
@@ -1169,13 +1166,13 @@ static int ghes_probe(struct platform_device *ghes_dev)
if (rc) {
pr_err(GHES_PFX "Failed to map GSI to IRQ for generic hardware error source: %d\n",
generic->header.source_id);
- goto err_edac_unreg;
+ goto err;
}
rc = request_irq(ghes->irq, ghes_irq_func, 0, "GHES IRQ", ghes);
if (rc) {
pr_err(GHES_PFX "Failed to register IRQ for generic hardware error source: %d\n",
generic->header.source_id);
- goto err_edac_unreg;
+ goto err;
}
break;
@@ -1204,8 +1201,7 @@ static int ghes_probe(struct platform_device *ghes_dev)
ghes_proc(ghes);
return 0;
-err_edac_unreg:
- ghes_edac_unregister(ghes);
+
err:
if (ghes) {
ghes_fini(ghes);
@@ -1255,8 +1251,6 @@ static int ghes_remove(struct platform_device *ghes_dev)
ghes_fini(ghes);
- ghes_edac_unregister(ghes);
-
kfree(ghes);
platform_set_drvdata(ghes_dev, NULL);
diff --git a/drivers/edac/Kconfig b/drivers/edac/Kconfig
index 96afb2aeed18..fdd8278ca89a 100644
--- a/drivers/edac/Kconfig
+++ b/drivers/edac/Kconfig
@@ -53,8 +53,8 @@ config EDAC_DECODE_MCE
has been initialized.
config EDAC_GHES
- bool "Output ACPI APEI/GHES BIOS detected errors via EDAC"
- depends on ACPI_APEI_GHES && (EDAC=y)
+ tristate "Output ACPI APEI/GHES BIOS detected errors via EDAC"
+ depends on ACPI_APEI_GHES
help
Not all machines support hardware-driven error report. Some of those
provide a BIOS-driven error report mechanism via ACPI, using the
diff --git a/drivers/edac/ghes_edac.c b/drivers/edac/ghes_edac.c
index 6f80eb65c26c..ecd34b8bd27e 100644
--- a/drivers/edac/ghes_edac.c
+++ b/drivers/edac/ghes_edac.c
@@ -5,6 +5,9 @@
* License version 2.
*
* Copyright (c) 2013 by Mauro Carvalho Chehab
+ * (c) 2017 Borislav Petkov
+ *
+ * Borislav Petkov: turn it into a proper module.
*
* Red Hat Inc. http://www.redhat.com
*/
@@ -28,10 +31,10 @@ struct ghes_edac_pvt {
char msg[80];
};
-static LIST_HEAD(ghes_reglist);
-static DEFINE_MUTEX(ghes_edac_lock);
-static int ghes_edac_mc_num;
+static struct ghes_edac_pvt *ghes_pvt;
+/* Hand it into EDAC's core so that we have a device to operate on. */
+static struct device dummy_dev;
/* Memory Device - Type 17 of SMBIOS spec */
struct memdev_dmi_entry {
@@ -163,24 +166,21 @@ static void ghes_edac_dmidecode(const struct dmi_header *dh, void *arg)
}
}
-void ghes_edac_report_mem_error(struct ghes *ghes, int sev,
- struct cper_sec_mem_err *mem_err)
+static int report_mem_error(struct notifier_block *nb, unsigned long sev, void *data)
{
+ struct cper_sec_mem_err *mem_err = data;
enum hw_event_mc_err_type type;
struct edac_raw_error_desc *e;
struct mem_ctl_info *mci;
- struct ghes_edac_pvt *pvt = NULL;
- char *p;
+ struct ghes_edac_pvt *pvt = ghes_pvt;
u8 grain_bits;
+ char *p;
- list_for_each_entry(pvt, &ghes_reglist, list) {
- if (ghes == pvt->ghes)
- break;
- }
if (!pvt) {
- pr_err("Internal error: Can't find EDAC structure\n");
- return;
+ edac_pr_err("Internal error: Can't find EDAC structure\n");
+ return NOTIFY_DONE;
}
+
mci = pvt->mci;
e = &mci->error_desc;
@@ -400,23 +400,40 @@ void ghes_edac_report_mem_error(struct ghes *ghes, int sev,
/* Report the error via EDAC API */
edac_raw_mc_handle_error(type, mci, e);
+
+ return NOTIFY_DONE;
}
-EXPORT_SYMBOL_GPL(ghes_edac_report_mem_error);
-int ghes_edac_register(struct ghes *ghes, struct device *dev)
+static struct notifier_block ghes_nb = {
+ .notifier_call = report_mem_error,
+};
+
+static const char * const fake_msg =
+"This EDAC driver relies on BIOS to enumerate memory and get error reports.\n"
+"Unfortunately, not all BIOSes reflect the memory layout correctly.\n"
+"So, the end result of using this driver varies from vendor to vendor.\n"
+"If you find incorrect reports, please contact your hardware vendor\n"
+"to correct its BIOS.";
+
+static const char * const super_crap_msg =
+"This system has a very crappy BIOS: It doesn't even list the DIMMS.\n"
+"Its SMBIOS info is wrong. It is doubtful that the error report would\n"
+"work on such system. Use this driver with caution.";
+
+static int __init ghes_edac_register(void)
{
+ struct ghes_edac_pvt *pvt = ghes_pvt;
bool fake = false;
int rc, num_dimm = 0;
struct mem_ctl_info *mci;
struct edac_mc_layer layers[1];
- struct ghes_edac_pvt *pvt;
struct ghes_edac_dimm_fill dimm_fill;
/* Get the number of DIMMs */
dmi_walk(ghes_edac_count_dimms, &num_dimm);
/* Check if we've got a bogus BIOS */
- if (num_dimm == 0) {
+ if (!num_dimm) {
fake = true;
num_dimm = 1;
}
@@ -429,21 +446,17 @@ int ghes_edac_register(struct ghes *ghes, struct device *dev)
* We need to serialize edac_mc_alloc() and edac_mc_add_mc(),
* to avoid duplicated memory controller numbers
*/
- mutex_lock(&ghes_edac_lock);
- mci = edac_mc_alloc(ghes_edac_mc_num, ARRAY_SIZE(layers), layers,
- sizeof(*pvt));
+ mci = edac_mc_alloc(1, ARRAY_SIZE(layers), layers, sizeof(*pvt));
if (!mci) {
- pr_info("Can't allocate memory for EDAC data\n");
- mutex_unlock(&ghes_edac_lock);
+ edac_pr_err("Can't allocate memory for EDAC data\n");
return -ENOMEM;
}
pvt = mci->pvt_info;
memset(pvt, 0, sizeof(*pvt));
- list_add_tail(&pvt->list, &ghes_reglist);
- pvt->ghes = ghes;
pvt->mci = mci;
- mci->pdev = dev;
+
+ mci->pdev = &dummy_dev;
mci->mtype_cap = MEM_FLAG_EMPTY;
mci->edac_ctl_cap = EDAC_FLAG_NONE;
@@ -452,21 +465,12 @@ int ghes_edac_register(struct ghes *ghes, struct device *dev)
mci->ctl_name = "ghes_edac";
mci->dev_name = "ghes";
- if (!ghes_edac_mc_num) {
- if (!fake) {
- pr_info("This EDAC driver relies on BIOS to enumerate memory and get error reports.\n");
- pr_info("Unfortunately, not all BIOSes reflect the memory layout correctly.\n");
- pr_info("So, the end result of using this driver varies from vendor to vendor.\n");
- pr_info("If you find incorrect reports, please contact your hardware vendor\n");
- pr_info("to correct its BIOS.\n");
- pr_info("This system has %d DIMM sockets.\n",
- num_dimm);
- } else {
- pr_info("This system has a very crappy BIOS: It doesn't even list the DIMMS.\n");
- pr_info("Its SMBIOS info is wrong. It is doubtful that the error report would\n");
- pr_info("work on such system. Use this driver with caution\n");
- }
- }
+ if (!fake)
+ edac_pr_info("%s\n", fake_msg);
+ else
+ edac_pr_info("%s\n", super_crap_msg);
+
+ edac_pr_info("This system has %d DIMM sockets.\n", num_dimm);
if (!fake) {
/*
@@ -475,13 +479,11 @@ int ghes_edac_register(struct ghes *ghes, struct device *dev)
* Keep it in blank for the other memory controllers, as
* there's no reliable way to properly credit each DIMM to
* the memory controller, as different BIOSes fill the
- * DMI bank location fields on different ways
+ * DMI bank location fields in different ways.
*/
- if (!ghes_edac_mc_num) {
- dimm_fill.count = 0;
- dimm_fill.mci = mci;
- dmi_walk(ghes_edac_dmidecode, &dimm_fill);
- }
+ dimm_fill.count = 0;
+ dimm_fill.mci = mci;
+ dmi_walk(ghes_edac_dmidecode, &dimm_fill);
} else {
struct dimm_info *dimm = EDAC_DIMM_PTR(mci->layers, mci->dimms,
mci->n_layers, 0, 0, 0);
@@ -495,30 +497,31 @@ int ghes_edac_register(struct ghes *ghes, struct device *dev)
rc = edac_mc_add_mc(mci);
if (rc < 0) {
- pr_info("Can't register at EDAC core\n");
+ edac_pr_err("Can't register with EDAC core\n");
edac_mc_free(mci);
- mutex_unlock(&ghes_edac_lock);
return -ENODEV;
}
- ghes_edac_mc_num++;
- mutex_unlock(&ghes_edac_lock);
+ ghes_register_edac_chain(&ghes_nb);
+
return 0;
}
-EXPORT_SYMBOL_GPL(ghes_edac_register);
+module_init(ghes_edac_register);
-void ghes_edac_unregister(struct ghes *ghes)
+static void __exit ghes_edac_unregister(void)
{
struct mem_ctl_info *mci;
- struct ghes_edac_pvt *pvt, *tmp;
-
- list_for_each_entry_safe(pvt, tmp, &ghes_reglist, list) {
- if (ghes == pvt->ghes) {
- mci = pvt->mci;
- edac_mc_del_mc(mci->pdev);
- edac_mc_free(mci);
- list_del(&pvt->list);
- }
- }
+
+ ghes_unregister_edac_chain(&ghes_nb);
+
+ mci = find_mci_by_dev(&dummy_dev);
+ WARN_ON(!mci);
+
+ edac_mc_del_mc(mci->pdev);
+ edac_mc_free(mci);
+
}
-EXPORT_SYMBOL_GPL(ghes_edac_unregister);
+module_exit(ghes_edac_unregister);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("GHES error decoding module");
diff --git a/include/acpi/ghes.h b/include/acpi/ghes.h
index 506b6a197738..c02b8eb91bd6 100644
--- a/include/acpi/ghes.h
+++ b/include/acpi/ghes.h
@@ -51,31 +51,6 @@ enum {
GHES_SEV_PANIC = 0x3,
};
-/* From drivers/edac/ghes_edac.c */
-
-#ifdef CONFIG_EDAC_GHES
-void ghes_edac_report_mem_error(struct ghes *ghes, int sev,
- struct cper_sec_mem_err *mem_err);
-
-int ghes_edac_register(struct ghes *ghes, struct device *dev);
-
-void ghes_edac_unregister(struct ghes *ghes);
-
-#else
-static inline void ghes_edac_report_mem_error(struct ghes *ghes, int sev,
- struct cper_sec_mem_err *mem_err)
-{
-}
-
-static inline int ghes_edac_register(struct ghes *ghes, struct device *dev)
-{
- return 0;
-}
-
-static inline void ghes_edac_unregister(struct ghes *ghes)
-{
-}
-#endif
void ghes_register_edac_chain(struct notifier_block *nb);
void ghes_unregister_edac_chain(struct notifier_block *nb);
--
2.14.0.rc0