Commit dc4e8c07e9e2 ("ACPI: APEI: explicit init of HEST and GHES in apci_init()") introduced a bug that ghes_edac_register() would be invoked before edac_init(). Because at that time, the bus "edac" hasn't been even registered, this created sysfs /devices/mc0 instead of /sys/devices/system/edac/mc/mc0 on an Ampere eMag server. The solution is modularizing the ghes_edac driver. Use a list to save the probing devices in ghes_probe(), and defer the ghes_edac_register() to the new ghes_edac module_init() by iterating over the devices list. To resolve the build dependency of ghes_edac_report_mem_error() for ghes, introduce a notifier which is registered by ghes_edac module. atomic notifier is used because ghes_proc_in_irq() is in the irq context. Co-developed-by: Borislav Petkov <bp@xxxxxxxxx> Signed-off-by: Borislav Petkov <bp@xxxxxxxxx> Signed-off-by: Jia He <justin.he@xxxxxxx> Fixes: dc4e8c07e9e2 ("ACPI: APEI: explicit init of HEST and GHES in apci_init()") Cc: stable@xxxxxxxxxx Cc: Shuai Xue <xueshuai@xxxxxxxxxxxxxxxxx> --- drivers/acpi/apei/ghes.c | 49 +++++++++++++++++++++++--- drivers/edac/Kconfig | 4 +-- drivers/edac/ghes_edac.c | 74 ++++++++++++++++++++++++++++------------ include/acpi/ghes.h | 33 +++++------------- 4 files changed, 107 insertions(+), 53 deletions(-) diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c index d91ad378c00d..ed6519f3d45b 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 +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; @@ -118,6 +120,9 @@ module_param_named(disable, ghes_disable, bool, 0); static LIST_HEAD(ghes_hed); static DEFINE_MUTEX(ghes_list_mutex); +static LIST_HEAD(ghes_devs); +static DEFINE_MUTEX(ghes_devs_mutex); + /* * Because the memory area used to transfer hardware error information * from BIOS to Linux can be determined only in NMI, IRQ or timer @@ -645,7 +650,7 @@ 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); @@ -1376,7 +1381,11 @@ 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); + list_add_tail(&ghes->elist, &ghes_devs); + mutex_unlock(&ghes_devs_mutex); /* Handle any pending errors right away */ spin_lock_irqsave(&ghes_notify_lock_irq, flags); @@ -1440,8 +1449,6 @@ static int ghes_remove(struct platform_device *ghes_dev) ghes_fini(ghes); - ghes_edac_unregister(ghes); - kfree(ghes); platform_set_drvdata(ghes_dev, NULL); @@ -1497,3 +1504,37 @@ void __init acpi_ghes_init(void) else pr_info(GHES_PFX "Failed to enable APEI firmware first mode.\n"); } + +/* + * Known x86 systems that prefer GHES error reporting: + */ +static struct acpi_platform_list plat_list[] = { + {"HPE ", "Server ", 0, ACPI_SIG_FADT, all_versions}, + { } /* End */ +}; + +struct list_head *ghes_get_devices(bool force) +{ + int idx = -1; + + if (IS_ENABLED(CONFIG_X86)) { + idx = acpi_match_platform_list(plat_list); + if (idx < 0 && !force) + return NULL; + } + + return &ghes_devs; +} +EXPORT_SYMBOL_GPL(ghes_get_devices); + +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/Kconfig b/drivers/edac/Kconfig index 17562cf1fe97..df45db81858b 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 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 c8fa7dcfdbd0..3bdf8469882d 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 @@ -59,6 +60,8 @@ module_param(force_load, bool, 0); static bool system_scanned; +static struct list_head *ghes_devs; + /* Memory Device - Type 17 of SMBIOS spec */ struct memdev_dmi_entry { u8 type; @@ -267,11 +270,14 @@ 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 +288,7 @@ 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); @@ -374,36 +380,24 @@ 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; } -/* - * Known systems that are safe to enable this module. - */ -static struct acpi_platform_list plat_list[] = { - {"HPE ", "Server ", 0, ACPI_SIG_FADT, all_versions}, - { } /* End */ +static struct notifier_block ghes_edac_mem_err_nb = { + .notifier_call = ghes_edac_report_mem_error, + .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; struct ghes_pvt *pvt; struct edac_mc_layer layers[1]; unsigned long flags; - int idx = -1; int rc = 0; - if (IS_ENABLED(CONFIG_X86)) { - /* Check if safe to enable on this system */ - idx = acpi_match_platform_list(plat_list); - if (!force_load && idx < 0) - return -ENODEV; - } else { - force_load = true; - idx = 0; - } - /* finish another registration/unregistration instance first */ mutex_lock(&ghes_reg_mutex); @@ -447,7 +441,7 @@ int ghes_edac_register(struct ghes *ghes, struct device *dev) 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"); - } else if (idx < 0) { + } else if (force_load) { 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"); @@ -503,6 +497,8 @@ 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); @@ -517,7 +513,7 @@ int ghes_edac_register(struct ghes *ghes, struct device *dev) 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; @@ -548,6 +544,40 @@ 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); } + +static int __init ghes_edac_init(void) +{ + struct ghes *g, *g_tmp; + + ghes_devs = ghes_get_devices(force_load); + if (!ghes_devs) + return -ENODEV; + + if (!IS_ENABLED(CONFIG_X86)) + force_load = true; + + 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 module via EDAC"); diff --git a/include/acpi/ghes.h b/include/acpi/ghes.h index 34fb3431a8f3..150c0b9500d6 100644 --- a/include/acpi/ghes.h +++ b/include/acpi/ghes.h @@ -27,6 +27,8 @@ struct ghes { struct timer_list timer; unsigned int irq; }; + struct device *dev; + struct list_head elist; }; struct ghes_estatus_node { @@ -69,35 +71,13 @@ 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); +struct list_head *ghes_get_devices(bool force); +#else +static inline struct list_head *ghes_get_devices(bool force) { return NULL; } #endif 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; -} - -static inline void ghes_edac_unregister(struct ghes *ghes) -{ -} -#endif - static inline int acpi_hest_get_version(struct acpi_hest_generic_data *gdata) { return gdata->revision >> 8; @@ -145,4 +125,7 @@ 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