[PATCH v10 2/7] EDAC/ghes: Add a notifier for reporting memory errors

Jia He
2022-10-18T08:27:44Z

To make a proper module, add a notifier for reporting memory errors. Use
an atomic notifier because calls sites like ghes_proc_in_irq() run in
interrupt context.

Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Jia He <justin.he@arm.com>
---
drivers/acpi/apei/ghes.c | 16 +++++++++++++++-
drivers/edac/ghes_edac.c | 19 +++++++++++++++++--
include/acpi/ghes.h | 10 +++-------
3 files changed, 35 insertions(+), 10 deletions(-)

diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
index d91ad378c00d..8cb65f757d06 100644
--- a/drivers/acpi/apei/ghes.c
+++ b/drivers/acpi/apei/ghes.c
@@ -94,6 +94,8 @@
#define FIX_APEI_GHES_SDEI_CRITICAL __end_of_fixed_addresses
#endif

+static ATOMIC_NOTIFIER_HEAD(ghes_report_chain);
+
static inline bool is_hest_type_generic_v2(struct ghes *ghes)
{
return ghes->generic->header.type == ACPI_HEST_TYPE_GENERIC_ERROR_V2;
@@ -645,7 +647,7 @@ static bool 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(sev, mem_err);
+ atomic_notifier_call_chain(&ghes_report_chain, sev, mem_err);

arch_apei_report_mem_error(sev, mem_err);
queued = ghes_handle_memory_failure(gdata, sev);
@@ -1497,3 +1499,15 @@ void __init acpi_ghes_init(void)
else
pr_info(GHES_PFX "Failed to enable APEI firmware first mode.\n");
}
+
+void ghes_register_report_chain(struct notifier_block *nb)
+{
+ atomic_notifier_chain_register(&ghes_report_chain, nb);
+}
+EXPORT_SYMBOL_GPL(ghes_register_report_chain);
+
+void ghes_unregister_report_chain(struct notifier_block *nb)
+{
+ atomic_notifier_chain_unregister(&ghes_report_chain, nb);
+}
+EXPORT_SYMBOL_GPL(ghes_unregister_report_chain);
diff --git a/drivers/edac/ghes_edac.c b/drivers/edac/ghes_edac.c
index c8fa7dcfdbd0..7b8d56a769f6 100644
--- a/drivers/edac/ghes_edac.c
+++ b/drivers/edac/ghes_edac.c
@@ -14,6 +14,7 @@
#include <linux/dmi.h>
#include "edac_module.h"
#include <ras/ras_event.h>
+#include <linux/notifier.h>

#define OTHER_DETAIL_LEN 400

@@ -267,11 +268,14 @@ static int print_mem_error_other_detail(const struct cper_sec_mem_err *mem, char
return n;
}

-void ghes_edac_report_mem_error(int sev, struct cper_sec_mem_err *mem_err)
+static int ghes_edac_report_mem_error(struct notifier_block *nb,
+ unsigned long val, void *data)
{
+ struct cper_sec_mem_err *mem_err = (struct cper_sec_mem_err *)data;
struct cper_mem_err_compact cmem;
struct edac_raw_error_desc *e;
struct mem_ctl_info *mci;
+ unsigned long sev = val;
struct ghes_pvt *pvt;
unsigned long flags;
char *p;
@@ -282,7 +286,7 @@ void ghes_edac_report_mem_error(int sev, struct cper_sec_mem_err *mem_err)
* know.
*/
if (WARN_ON_ONCE(in_nmi()))
- return;
+ return NOTIFY_OK;

spin_lock_irqsave(&ghes_lock, flags);

@@ -374,8 +378,15 @@ void ghes_edac_report_mem_error(int sev, struct cper_sec_mem_err *mem_err)

unlock:
spin_unlock_irqrestore(&ghes_lock, flags);
+
+ return NOTIFY_OK;
}

+static struct notifier_block ghes_edac_mem_err_nb = {
+ .notifier_call = ghes_edac_report_mem_error,
+ .priority = 0,
+};
+
/*
* Known systems that are safe to enable this module.
*/
@@ -503,6 +514,8 @@ int ghes_edac_register(struct ghes *ghes, struct device *dev)
ghes_pvt = pvt;
spin_unlock_irqrestore(&ghes_lock, flags);

+ ghes_register_report_chain(&ghes_edac_mem_err_nb);
+
/* only set on success */
refcount_set(&ghes_refcount, 1);

@@ -548,6 +561,8 @@ void ghes_edac_unregister(struct ghes *ghes)
if (mci)
edac_mc_free(mci);

+ ghes_unregister_report_chain(&ghes_edac_mem_err_nb);
+
unlock:
mutex_unlock(&ghes_reg_mutex);
}
diff --git a/include/acpi/ghes.h b/include/acpi/ghes.h
index 34fb3431a8f3..5cbd38b6e4e1 100644
--- a/include/acpi/ghes.h
+++ b/include/acpi/ghes.h
@@ -76,18 +76,11 @@ int ghes_estatus_pool_init(int num_ghes);
/* From drivers/edac/ghes_edac.c */

#ifdef CONFIG_EDAC_GHES
-void ghes_edac_report_mem_error(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(int sev,
- struct cper_sec_mem_err *mem_err)
-{
-}
-
static inline int ghes_edac_register(struct ghes *ghes, struct device *dev)
{
return -ENODEV;
@@ -145,4 +138,7 @@ int ghes_notify_sea(void);
static inline int ghes_notify_sea(void) { return -ENOENT; }
#endif

+struct notifier_block;
+extern void ghes_register_report_chain(struct notifier_block *nb);
+extern void ghes_unregister_report_chain(struct notifier_block *nb);
#endif /* GHES_H */
--
2.25.1