Commit 9057a3f7 authored by Jia He's avatar Jia He Committed by Borislav Petkov
Browse files

EDAC/ghes: Prepare to make ghes_edac a proper module 



To make ghes_edac a proper module, prepare to decouple its dependencies
from GHES.

Move the ghes_edac.force_load parameter to ghes.c in order to
properly control whether ghes_edac should be force-loaded: In
ghes_edac_register() it is too late to set the module flag.

Introduce a helper ghes_get_devices(), which returns the list of GHES
devices which got probed when the platform-check passes on the system.

The previous force_load check is not needed in ghes_edac_unregister()
since it will be checked in the module's init function of ghes_edac
later.

  [ bp: Massage. ]

Suggested-by: default avatarToshi Kani <toshi.kani@hpe.com>
Suggested-by: default avatarBorislav Petkov <bp@alien8.de>
Signed-off-by: default avatarJia He <justin.he@arm.com>
Signed-off-by: default avatarBorislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20221010023559.69655-4-justin.he@arm.com
parent 8e40612f

drivers/acpi/apei/ghes.c

+50 −0
Original line number Diff line number Diff line
@@ -109,6 +109,13 @@ static inline bool is_hest_type_generic_v2(struct ghes *ghes) 
bool ghes_disable;

module_param_named(disable, ghes_disable, bool, 0);



/*

 * "ghes.edac_force_enable" forcibly enables ghes_edac and skips the platform

 * check.

 */

static bool ghes_edac_force_enable;

module_param_named(edac_force_enable, ghes_edac_force_enable, bool, 0);



/*

 * All error sources notified with HED (Hardware Error Device) share a

 * single notifier callback, so they need to be linked and checked one
@@ -120,6 +127,13 @@ module_param_named(disable, ghes_disable, bool, 0); 
static LIST_HEAD(ghes_hed);

static DEFINE_MUTEX(ghes_list_mutex);



/*

 * A list of GHES devices which are given to the corresponding EDAC driver

 * ghes_edac for further use.

 */

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
@@ -1380,6 +1394,12 @@ static int ghes_probe(struct platform_device *ghes_dev) 


	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);

	ghes_proc(ghes);
@@ -1444,6 +1464,10 @@ static int ghes_remove(struct platform_device *ghes_dev) 


	ghes_edac_unregister(ghes);



	mutex_lock(&ghes_devs_mutex);

	list_del(&ghes->elist);

	mutex_unlock(&ghes_devs_mutex);



	kfree(ghes);



	platform_set_drvdata(ghes_dev, NULL);
@@ -1500,6 +1524,32 @@ void __init acpi_ghes_init(void) 
		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(void)

{

	int idx = -1;



	if (IS_ENABLED(CONFIG_X86)) {

		idx = acpi_match_platform_list(plat_list);

		if (idx < 0) {

			if (!ghes_edac_force_enable)

				return NULL;



			pr_warn_once("Force-loading ghes_edac on an unsupported platform. You're on your own!\n");

		}

	}



	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);

drivers/edac/ghes_edac.c

+2 −33
Original line number Diff line number Diff line
@@ -54,10 +54,6 @@ static DEFINE_MUTEX(ghes_reg_mutex); 
 */

static DEFINE_SPINLOCK(ghes_lock);



/* "ghes_edac.force_load=1" skips the platform check */

static bool __read_mostly force_load;

module_param(force_load, bool, 0);



static bool system_scanned;



/* Memory Device - Type 17 of SMBIOS spec */
@@ -387,14 +383,6 @@ static struct notifier_block ghes_edac_mem_err_nb = { 
	.priority	= 0,

};



/*

 * 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 */

};



int ghes_edac_register(struct ghes *ghes, struct device *dev)

{

	bool fake = false;
@@ -402,19 +390,8 @@ int ghes_edac_register(struct ghes *ghes, struct device *dev) 
	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);
@@ -458,15 +435,10 @@ 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) {

		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", ghes_hw.num_dimms);

	}



	pr_info("This system has %d DIMM sockets.\n", ghes_hw.num_dimms);



	if (!fake) {

		struct dimm_info *src, *dst;

		int i = 0;
@@ -535,9 +507,6 @@ void ghes_edac_unregister(struct ghes *ghes) 
	struct mem_ctl_info *mci;

	unsigned long flags;



	if (!force_load)

		return;



	mutex_lock(&ghes_reg_mutex);



	system_scanned = false;

include/acpi/ghes.h

+6 −0
Original line number Diff line number Diff line
@@ -27,6 +27,8 @@ struct ghes { 
		struct timer_list timer;

		unsigned int irq;

	};

	struct device *dev;

	struct list_head elist;

};



struct ghes_estatus_node {
@@ -80,6 +82,8 @@ 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)

{
@@ -89,6 +93,8 @@ static inline int ghes_edac_register(struct ghes *ghes, struct device *dev) 
static inline void ghes_edac_unregister(struct ghes *ghes)

{

}



static inline struct list_head *ghes_get_devices(void) { return NULL; }

#endif



static inline int acpi_hest_get_version(struct acpi_hest_generic_data *gdata)