EDAC/ghes: Make ghes_edac a proper module

Commit

  dc4e8c07e9e2 ("ACPI: APEI: explicit init of HEST and GHES in apci_init()")

introduced a bug leading to ghes_edac_register() to be invoked before
edac_init(). Because at that time the bus "edac" hadn't been even
registered, this created sysfs nodes as /devices/mc0 instead of
/sys/devices/system/edac/mc/mc0 on an Ampere eMag server.

Fix this by turning ghes_edac into a proper module.

The list of GHES devices returned is not protected from being modified
concurrently but it is pretty static as it gets created only during GHES
init and latter is not a module so...

  [ bp: Massage. ]

Fixes: dc4e8c07e9e2 ("ACPI: APEI: explicit init of HEST and GHES in apci_init()")
Co-developed-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Jia He <justin.he@arm.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20221010023559.69655-5-justin.he@arm.com

diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
index acab512741f6c545850371f1fa2a070105ef83ff..249cd01cb920904efd7ccbce9a6b4c1f30119d01 100644 (file)
--- a/drivers/acpi/apei/ghes.c
+++ b/drivers/acpi/apei/ghes.c
@@ -1392,8 +1392,6 @@ static int ghes_probe(struct platform_device *ghes_dev)
 
        platform_set_drvdata(ghes_dev, ghes);
 
-       ghes_edac_register(ghes, &ghes_dev->dev);
-
        ghes->dev = &ghes_dev->dev;
 
        mutex_lock(&ghes_devs_mutex);
@@ -1462,8 +1460,6 @@ static int ghes_remove(struct platform_device *ghes_dev)
 
        ghes_fini(ghes);
 
-       ghes_edac_unregister(ghes);
-
        mutex_lock(&ghes_devs_mutex);
        list_del(&ghes->elist);
        mutex_unlock(&ghes_devs_mutex);

diff --git a/drivers/edac/Kconfig b/drivers/edac/Kconfig
index 456602d373b7b1e71c438734aa6f7a032529ff47..cde0849cf8612aa736414e322c558e02f7e7d0f3 100644 (file)
--- 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
        select UEFI_CPER
        help
          Not all machines support hardware-driven error report. Some of those

diff --git a/drivers/edac/ghes_edac.c b/drivers/edac/ghes_edac.c
index b85a545d1cb030f022e22d71f314d7b5d8015691..cf2b618c1ada9528907de7f4dce272566053aad9 100644 (file)
--- a/drivers/edac/ghes_edac.c
+++ b/drivers/edac/ghes_edac.c
@@ -56,6 +56,8 @@ static DEFINE_SPINLOCK(ghes_lock);
 
 static bool system_scanned;
 
+static struct list_head *ghes_devs;
+
 /* Memory Device - Type 17 of SMBIOS spec */
 struct memdev_dmi_entry {
        u8 type;
@@ -383,7 +385,7 @@ static struct notifier_block ghes_edac_mem_err_nb = {
        .priority       = 0,
 };
 
-int ghes_edac_register(struct ghes *ghes, struct device *dev)
+static int ghes_edac_register(struct device *dev)
 {
        bool fake = false;
        struct mem_ctl_info *mci;
@@ -502,7 +504,7 @@ unlock:
        return rc;
 }
 
-void ghes_edac_unregister(struct ghes *ghes)
+static void ghes_edac_unregister(struct ghes *ghes)
 {
        struct mem_ctl_info *mci;
        unsigned long flags;
@@ -535,3 +537,37 @@ void ghes_edac_unregister(struct ghes *ghes)
 unlock:
        mutex_unlock(&ghes_reg_mutex);
 }
+
+static int __init ghes_edac_init(void)
+{
+       struct ghes *g, *g_tmp;
+
+       ghes_devs = ghes_get_devices();
+       if (!ghes_devs)
+               return -ENODEV;
+
+       if (list_empty(ghes_devs)) {
+               pr_info("GHES probing device list is empty");
+               return -ENODEV;
+       }
+
+       list_for_each_entry_safe(g, g_tmp, ghes_devs, elist) {
+               ghes_edac_register(g->dev);
+       }
+
+       return 0;
+}
+module_init(ghes_edac_init);
+
+static void __exit ghes_edac_exit(void)
+{
+       struct ghes *g, *g_tmp;
+
+       list_for_each_entry_safe(g, g_tmp, ghes_devs, elist) {
+               ghes_edac_unregister(g);
+       }
+}
+module_exit(ghes_edac_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Output ACPI APEI/GHES BIOS detected errors via EDAC");

diff --git a/include/acpi/ghes.h b/include/acpi/ghes.h
index ce693e9f07a0d8a38b471b99531424d0613b0124..2e785d3554d8671b23b1cc300781013432ddd0e8 100644 (file)
--- a/include/acpi/ghes.h
+++ b/include/acpi/ghes.h
@@ -71,32 +71,14 @@ int ghes_register_vendor_record_notifier(struct notifier_block *nb);
  * @nb: pointer to the notifier_block structure of the vendor record handler.
  */
 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 */
-
-#ifdef CONFIG_EDAC_GHES
-int ghes_edac_register(struct ghes *ghes, struct device *dev);
-
-void ghes_edac_unregister(struct ghes *ghes);
 
 struct list_head *ghes_get_devices(void);
-
 #else
-static inline int ghes_edac_register(struct ghes *ghes, struct device *dev)
-{
-       return -ENODEV;
-}
-
-static inline void ghes_edac_unregister(struct ghes *ghes)
-{
-}
-
 static inline struct list_head *ghes_get_devices(void) { return NULL; }
 #endif
 
+int ghes_estatus_pool_init(int num_ghes);
+
 static inline int acpi_hest_get_version(struct acpi_hest_generic_data *gdata)
 {
        return gdata->revision >> 8;