1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * GHES/EDAC Linux driver
4  *
5  * Copyright (c) 2013 by Mauro Carvalho Chehab
6  *
7  * Red Hat Inc. https://www.redhat.com
8  */
9 
10 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
11 
12 #include <acpi/ghes.h>
13 #include <linux/edac.h>
14 #include <linux/dmi.h>
15 #include "edac_module.h"
16 #include <ras/ras_event.h>
17 
18 struct ghes_pvt {
19 	struct mem_ctl_info *mci;
20 
21 	/* Buffers for the error handling routine */
22 	char other_detail[400];
23 	char msg[80];
24 };
25 
26 static refcount_t ghes_refcount = REFCOUNT_INIT(0);
27 
28 /*
29  * Access to ghes_pvt must be protected by ghes_lock. The spinlock
30  * also provides the necessary (implicit) memory barrier for the SMP
31  * case to make the pointer visible on another CPU.
32  */
33 static struct ghes_pvt *ghes_pvt;
34 
35 /*
36  * This driver's representation of the system hardware, as collected
37  * from DMI.
38  */
39 struct ghes_hw_desc {
40 	int num_dimms;
41 	struct dimm_info *dimms;
42 } ghes_hw;
43 
44 /* GHES registration mutex */
45 static DEFINE_MUTEX(ghes_reg_mutex);
46 
47 /*
48  * Sync with other, potentially concurrent callers of
49  * ghes_edac_report_mem_error(). We don't know what the
50  * "inventive" firmware would do.
51  */
52 static DEFINE_SPINLOCK(ghes_lock);
53 
54 /* "ghes_edac.force_load=1" skips the platform check */
55 static bool __read_mostly force_load;
56 module_param(force_load, bool, 0);
57 
58 static bool system_scanned;
59 
60 /* Memory Device - Type 17 of SMBIOS spec */
61 struct memdev_dmi_entry {
62 	u8 type;
63 	u8 length;
64 	u16 handle;
65 	u16 phys_mem_array_handle;
66 	u16 mem_err_info_handle;
67 	u16 total_width;
68 	u16 data_width;
69 	u16 size;
70 	u8 form_factor;
71 	u8 device_set;
72 	u8 device_locator;
73 	u8 bank_locator;
74 	u8 memory_type;
75 	u16 type_detail;
76 	u16 speed;
77 	u8 manufacturer;
78 	u8 serial_number;
79 	u8 asset_tag;
80 	u8 part_number;
81 	u8 attributes;
82 	u32 extended_size;
83 	u16 conf_mem_clk_speed;
84 } __attribute__((__packed__));
85 
find_dimm_by_handle(struct mem_ctl_info *mci, u16 handle)86 static struct dimm_info *find_dimm_by_handle(struct mem_ctl_info *mci, u16 handle)
87 {
88 	struct dimm_info *dimm;
89 
90 	mci_for_each_dimm(mci, dimm) {
91 		if (dimm->smbios_handle == handle)
92 			return dimm;
93 	}
94 
95 	return NULL;
96 }
97 
dimm_setup_label(struct dimm_info *dimm, u16 handle)98 static void dimm_setup_label(struct dimm_info *dimm, u16 handle)
99 {
100 	const char *bank = NULL, *device = NULL;
101 
102 	dmi_memdev_name(handle, &bank, &device);
103 
104 	/*
105 	 * Set to a NULL string when both bank and device are zero. In this case,
106 	 * the label assigned by default will be preserved.
107 	 */
108 	snprintf(dimm->label, sizeof(dimm->label), "%s%s%s",
109 		 (bank && *bank) ? bank : "",
110 		 (bank && *bank && device && *device) ? " " : "",
111 		 (device && *device) ? device : "");
112 }
113 
assign_dmi_dimm_info(struct dimm_info *dimm, struct memdev_dmi_entry *entry)114 static void assign_dmi_dimm_info(struct dimm_info *dimm, struct memdev_dmi_entry *entry)
115 {
116 	u16 rdr_mask = BIT(7) | BIT(13);
117 
118 	if (entry->size == 0xffff) {
119 		pr_info("Can't get DIMM%i size\n", dimm->idx);
120 		dimm->nr_pages = MiB_TO_PAGES(32);/* Unknown */
121 	} else if (entry->size == 0x7fff) {
122 		dimm->nr_pages = MiB_TO_PAGES(entry->extended_size);
123 	} else {
124 		if (entry->size & BIT(15))
125 			dimm->nr_pages = MiB_TO_PAGES((entry->size & 0x7fff) << 10);
126 		else
127 			dimm->nr_pages = MiB_TO_PAGES(entry->size);
128 	}
129 
130 	switch (entry->memory_type) {
131 	case 0x12:
132 		if (entry->type_detail & BIT(13))
133 			dimm->mtype = MEM_RDDR;
134 		else
135 			dimm->mtype = MEM_DDR;
136 		break;
137 	case 0x13:
138 		if (entry->type_detail & BIT(13))
139 			dimm->mtype = MEM_RDDR2;
140 		else
141 			dimm->mtype = MEM_DDR2;
142 		break;
143 	case 0x14:
144 		dimm->mtype = MEM_FB_DDR2;
145 		break;
146 	case 0x18:
147 		if (entry->type_detail & BIT(12))
148 			dimm->mtype = MEM_NVDIMM;
149 		else if (entry->type_detail & BIT(13))
150 			dimm->mtype = MEM_RDDR3;
151 		else
152 			dimm->mtype = MEM_DDR3;
153 		break;
154 	case 0x1a:
155 		if (entry->type_detail & BIT(12))
156 			dimm->mtype = MEM_NVDIMM;
157 		else if (entry->type_detail & BIT(13))
158 			dimm->mtype = MEM_RDDR4;
159 		else
160 			dimm->mtype = MEM_DDR4;
161 		break;
162 	default:
163 		if (entry->type_detail & BIT(6))
164 			dimm->mtype = MEM_RMBS;
165 		else if ((entry->type_detail & rdr_mask) == rdr_mask)
166 			dimm->mtype = MEM_RDR;
167 		else if (entry->type_detail & BIT(7))
168 			dimm->mtype = MEM_SDR;
169 		else if (entry->type_detail & BIT(9))
170 			dimm->mtype = MEM_EDO;
171 		else
172 			dimm->mtype = MEM_UNKNOWN;
173 	}
174 
175 	/*
176 	 * Actually, we can only detect if the memory has bits for
177 	 * checksum or not
178 	 */
179 	if (entry->total_width == entry->data_width)
180 		dimm->edac_mode = EDAC_NONE;
181 	else
182 		dimm->edac_mode = EDAC_SECDED;
183 
184 	dimm->dtype = DEV_UNKNOWN;
185 	dimm->grain = 128;		/* Likely, worse case */
186 
187 	dimm_setup_label(dimm, entry->handle);
188 
189 	if (dimm->nr_pages) {
190 		edac_dbg(1, "DIMM%i: %s size = %d MB%s\n",
191 			dimm->idx, edac_mem_types[dimm->mtype],
192 			PAGES_TO_MiB(dimm->nr_pages),
193 			(dimm->edac_mode != EDAC_NONE) ? "(ECC)" : "");
194 		edac_dbg(2, "\ttype %d, detail 0x%02x, width %d(total %d)\n",
195 			entry->memory_type, entry->type_detail,
196 			entry->total_width, entry->data_width);
197 	}
198 
199 	dimm->smbios_handle = entry->handle;
200 }
201 
enumerate_dimms(const struct dmi_header *dh, void *arg)202 static void enumerate_dimms(const struct dmi_header *dh, void *arg)
203 {
204 	struct memdev_dmi_entry *entry = (struct memdev_dmi_entry *)dh;
205 	struct ghes_hw_desc *hw = (struct ghes_hw_desc *)arg;
206 	struct dimm_info *d;
207 
208 	if (dh->type != DMI_ENTRY_MEM_DEVICE)
209 		return;
210 
211 	/* Enlarge the array with additional 16 */
212 	if (!hw->num_dimms || !(hw->num_dimms % 16)) {
213 		struct dimm_info *new;
214 
215 		new = krealloc(hw->dimms, (hw->num_dimms + 16) * sizeof(struct dimm_info),
216 			        GFP_KERNEL);
217 		if (!new) {
218 			WARN_ON_ONCE(1);
219 			return;
220 		}
221 
222 		hw->dimms = new;
223 	}
224 
225 	d = &hw->dimms[hw->num_dimms];
226 	d->idx = hw->num_dimms;
227 
228 	assign_dmi_dimm_info(d, entry);
229 
230 	hw->num_dimms++;
231 }
232 
ghes_scan_system(void)233 static void ghes_scan_system(void)
234 {
235 	if (system_scanned)
236 		return;
237 
238 	dmi_walk(enumerate_dimms, &ghes_hw);
239 
240 	system_scanned = true;
241 }
242 
ghes_edac_report_mem_error(int sev, struct cper_sec_mem_err *mem_err)243 void ghes_edac_report_mem_error(int sev, struct cper_sec_mem_err *mem_err)
244 {
245 	struct edac_raw_error_desc *e;
246 	struct mem_ctl_info *mci;
247 	struct ghes_pvt *pvt;
248 	unsigned long flags;
249 	char *p;
250 
251 	/*
252 	 * We can do the locking below because GHES defers error processing
253 	 * from NMI to IRQ context. Whenever that changes, we'd at least
254 	 * know.
255 	 */
256 	if (WARN_ON_ONCE(in_nmi()))
257 		return;
258 
259 	spin_lock_irqsave(&ghes_lock, flags);
260 
261 	pvt = ghes_pvt;
262 	if (!pvt)
263 		goto unlock;
264 
265 	mci = pvt->mci;
266 	e = &mci->error_desc;
267 
268 	/* Cleans the error report buffer */
269 	memset(e, 0, sizeof (*e));
270 	e->error_count = 1;
271 	e->grain = 1;
272 	e->msg = pvt->msg;
273 	e->other_detail = pvt->other_detail;
274 	e->top_layer = -1;
275 	e->mid_layer = -1;
276 	e->low_layer = -1;
277 	*pvt->other_detail = '\0';
278 	*pvt->msg = '\0';
279 
280 	switch (sev) {
281 	case GHES_SEV_CORRECTED:
282 		e->type = HW_EVENT_ERR_CORRECTED;
283 		break;
284 	case GHES_SEV_RECOVERABLE:
285 		e->type = HW_EVENT_ERR_UNCORRECTED;
286 		break;
287 	case GHES_SEV_PANIC:
288 		e->type = HW_EVENT_ERR_FATAL;
289 		break;
290 	default:
291 	case GHES_SEV_NO:
292 		e->type = HW_EVENT_ERR_INFO;
293 	}
294 
295 	edac_dbg(1, "error validation_bits: 0x%08llx\n",
296 		 (long long)mem_err->validation_bits);
297 
298 	/* Error type, mapped on e->msg */
299 	if (mem_err->validation_bits & CPER_MEM_VALID_ERROR_TYPE) {
300 		p = pvt->msg;
301 		switch (mem_err->error_type) {
302 		case 0:
303 			p += sprintf(p, "Unknown");
304 			break;
305 		case 1:
306 			p += sprintf(p, "No error");
307 			break;
308 		case 2:
309 			p += sprintf(p, "Single-bit ECC");
310 			break;
311 		case 3:
312 			p += sprintf(p, "Multi-bit ECC");
313 			break;
314 		case 4:
315 			p += sprintf(p, "Single-symbol ChipKill ECC");
316 			break;
317 		case 5:
318 			p += sprintf(p, "Multi-symbol ChipKill ECC");
319 			break;
320 		case 6:
321 			p += sprintf(p, "Master abort");
322 			break;
323 		case 7:
324 			p += sprintf(p, "Target abort");
325 			break;
326 		case 8:
327 			p += sprintf(p, "Parity Error");
328 			break;
329 		case 9:
330 			p += sprintf(p, "Watchdog timeout");
331 			break;
332 		case 10:
333 			p += sprintf(p, "Invalid address");
334 			break;
335 		case 11:
336 			p += sprintf(p, "Mirror Broken");
337 			break;
338 		case 12:
339 			p += sprintf(p, "Memory Sparing");
340 			break;
341 		case 13:
342 			p += sprintf(p, "Scrub corrected error");
343 			break;
344 		case 14:
345 			p += sprintf(p, "Scrub uncorrected error");
346 			break;
347 		case 15:
348 			p += sprintf(p, "Physical Memory Map-out event");
349 			break;
350 		default:
351 			p += sprintf(p, "reserved error (%d)",
352 				     mem_err->error_type);
353 		}
354 	} else {
355 		strcpy(pvt->msg, "unknown error");
356 	}
357 
358 	/* Error address */
359 	if (mem_err->validation_bits & CPER_MEM_VALID_PA) {
360 		e->page_frame_number = PHYS_PFN(mem_err->physical_addr);
361 		e->offset_in_page = offset_in_page(mem_err->physical_addr);
362 	}
363 
364 	/* Error grain */
365 	if (mem_err->validation_bits & CPER_MEM_VALID_PA_MASK)
366 		e->grain = ~mem_err->physical_addr_mask + 1;
367 
368 	/* Memory error location, mapped on e->location */
369 	p = e->location;
370 	if (mem_err->validation_bits & CPER_MEM_VALID_NODE)
371 		p += sprintf(p, "node:%d ", mem_err->node);
372 	if (mem_err->validation_bits & CPER_MEM_VALID_CARD)
373 		p += sprintf(p, "card:%d ", mem_err->card);
374 	if (mem_err->validation_bits & CPER_MEM_VALID_MODULE)
375 		p += sprintf(p, "module:%d ", mem_err->module);
376 	if (mem_err->validation_bits & CPER_MEM_VALID_RANK_NUMBER)
377 		p += sprintf(p, "rank:%d ", mem_err->rank);
378 	if (mem_err->validation_bits & CPER_MEM_VALID_BANK)
379 		p += sprintf(p, "bank:%d ", mem_err->bank);
380 	if (mem_err->validation_bits & CPER_MEM_VALID_BANK_GROUP)
381 		p += sprintf(p, "bank_group:%d ",
382 			     mem_err->bank >> CPER_MEM_BANK_GROUP_SHIFT);
383 	if (mem_err->validation_bits & CPER_MEM_VALID_BANK_ADDRESS)
384 		p += sprintf(p, "bank_address:%d ",
385 			     mem_err->bank & CPER_MEM_BANK_ADDRESS_MASK);
386 	if (mem_err->validation_bits & (CPER_MEM_VALID_ROW | CPER_MEM_VALID_ROW_EXT)) {
387 		u32 row = mem_err->row;
388 
389 		row |= cper_get_mem_extension(mem_err->validation_bits, mem_err->extended);
390 		p += sprintf(p, "row:%d ", row);
391 	}
392 	if (mem_err->validation_bits & CPER_MEM_VALID_COLUMN)
393 		p += sprintf(p, "col:%d ", mem_err->column);
394 	if (mem_err->validation_bits & CPER_MEM_VALID_BIT_POSITION)
395 		p += sprintf(p, "bit_pos:%d ", mem_err->bit_pos);
396 	if (mem_err->validation_bits & CPER_MEM_VALID_MODULE_HANDLE) {
397 		const char *bank = NULL, *device = NULL;
398 		struct dimm_info *dimm;
399 
400 		dmi_memdev_name(mem_err->mem_dev_handle, &bank, &device);
401 		if (bank != NULL && device != NULL)
402 			p += sprintf(p, "DIMM location:%s %s ", bank, device);
403 		else
404 			p += sprintf(p, "DIMM DMI handle: 0x%.4x ",
405 				     mem_err->mem_dev_handle);
406 
407 		dimm = find_dimm_by_handle(mci, mem_err->mem_dev_handle);
408 		if (dimm) {
409 			e->top_layer = dimm->idx;
410 			strcpy(e->label, dimm->label);
411 		}
412 	}
413 	if (mem_err->validation_bits & CPER_MEM_VALID_CHIP_ID)
414 		p += sprintf(p, "chipID: %d ",
415 			     mem_err->extended >> CPER_MEM_CHIP_ID_SHIFT);
416 	if (p > e->location)
417 		*(p - 1) = '\0';
418 
419 	if (!*e->label)
420 		strcpy(e->label, "unknown memory");
421 
422 	/* All other fields are mapped on e->other_detail */
423 	p = pvt->other_detail;
424 	p += snprintf(p, sizeof(pvt->other_detail),
425 		"APEI location: %s ", e->location);
426 	if (mem_err->validation_bits & CPER_MEM_VALID_ERROR_STATUS) {
427 		u64 status = mem_err->error_status;
428 
429 		p += sprintf(p, "status(0x%016llx): ", (long long)status);
430 		switch ((status >> 8) & 0xff) {
431 		case 1:
432 			p += sprintf(p, "Error detected internal to the component ");
433 			break;
434 		case 16:
435 			p += sprintf(p, "Error detected in the bus ");
436 			break;
437 		case 4:
438 			p += sprintf(p, "Storage error in DRAM memory ");
439 			break;
440 		case 5:
441 			p += sprintf(p, "Storage error in TLB ");
442 			break;
443 		case 6:
444 			p += sprintf(p, "Storage error in cache ");
445 			break;
446 		case 7:
447 			p += sprintf(p, "Error in one or more functional units ");
448 			break;
449 		case 8:
450 			p += sprintf(p, "component failed self test ");
451 			break;
452 		case 9:
453 			p += sprintf(p, "Overflow or undervalue of internal queue ");
454 			break;
455 		case 17:
456 			p += sprintf(p, "Virtual address not found on IO-TLB or IO-PDIR ");
457 			break;
458 		case 18:
459 			p += sprintf(p, "Improper access error ");
460 			break;
461 		case 19:
462 			p += sprintf(p, "Access to a memory address which is not mapped to any component ");
463 			break;
464 		case 20:
465 			p += sprintf(p, "Loss of Lockstep ");
466 			break;
467 		case 21:
468 			p += sprintf(p, "Response not associated with a request ");
469 			break;
470 		case 22:
471 			p += sprintf(p, "Bus parity error - must also set the A, C, or D Bits ");
472 			break;
473 		case 23:
474 			p += sprintf(p, "Detection of a PATH_ERROR ");
475 			break;
476 		case 25:
477 			p += sprintf(p, "Bus operation timeout ");
478 			break;
479 		case 26:
480 			p += sprintf(p, "A read was issued to data that has been poisoned ");
481 			break;
482 		default:
483 			p += sprintf(p, "reserved ");
484 			break;
485 		}
486 	}
487 	if (mem_err->validation_bits & CPER_MEM_VALID_REQUESTOR_ID)
488 		p += sprintf(p, "requestorID: 0x%016llx ",
489 			     (long long)mem_err->requestor_id);
490 	if (mem_err->validation_bits & CPER_MEM_VALID_RESPONDER_ID)
491 		p += sprintf(p, "responderID: 0x%016llx ",
492 			     (long long)mem_err->responder_id);
493 	if (mem_err->validation_bits & CPER_MEM_VALID_TARGET_ID)
494 		p += sprintf(p, "targetID: 0x%016llx ",
495 			     (long long)mem_err->responder_id);
496 	if (p > pvt->other_detail)
497 		*(p - 1) = '\0';
498 
499 	edac_raw_mc_handle_error(e);
500 
501 unlock:
502 	spin_unlock_irqrestore(&ghes_lock, flags);
503 }
504 
505 /*
506  * Known systems that are safe to enable this module.
507  */
508 static struct acpi_platform_list plat_list[] = {
509 	{"HPE   ", "Server  ", 0, ACPI_SIG_FADT, all_versions},
510 	{ } /* End */
511 };
512 
ghes_edac_register(struct ghes *ghes, struct device *dev)513 int ghes_edac_register(struct ghes *ghes, struct device *dev)
514 {
515 	bool fake = false;
516 	struct mem_ctl_info *mci;
517 	struct ghes_pvt *pvt;
518 	struct edac_mc_layer layers[1];
519 	unsigned long flags;
520 	int idx = -1;
521 	int rc = 0;
522 
523 	if (IS_ENABLED(CONFIG_X86)) {
524 		/* Check if safe to enable on this system */
525 		idx = acpi_match_platform_list(plat_list);
526 		if (!force_load && idx < 0)
527 			return -ENODEV;
528 	} else {
529 		force_load = true;
530 		idx = 0;
531 	}
532 
533 	/* finish another registration/unregistration instance first */
534 	mutex_lock(&ghes_reg_mutex);
535 
536 	/*
537 	 * We have only one logical memory controller to which all DIMMs belong.
538 	 */
539 	if (refcount_inc_not_zero(&ghes_refcount))
540 		goto unlock;
541 
542 	ghes_scan_system();
543 
544 	/* Check if we've got a bogus BIOS */
545 	if (!ghes_hw.num_dimms) {
546 		fake = true;
547 		ghes_hw.num_dimms = 1;
548 	}
549 
550 	layers[0].type = EDAC_MC_LAYER_ALL_MEM;
551 	layers[0].size = ghes_hw.num_dimms;
552 	layers[0].is_virt_csrow = true;
553 
554 	mci = edac_mc_alloc(0, ARRAY_SIZE(layers), layers, sizeof(struct ghes_pvt));
555 	if (!mci) {
556 		pr_info("Can't allocate memory for EDAC data\n");
557 		rc = -ENOMEM;
558 		goto unlock;
559 	}
560 
561 	pvt		= mci->pvt_info;
562 	pvt->mci	= mci;
563 
564 	mci->pdev = dev;
565 	mci->mtype_cap = MEM_FLAG_EMPTY;
566 	mci->edac_ctl_cap = EDAC_FLAG_NONE;
567 	mci->edac_cap = EDAC_FLAG_NONE;
568 	mci->mod_name = "ghes_edac.c";
569 	mci->ctl_name = "ghes_edac";
570 	mci->dev_name = "ghes";
571 
572 	if (fake) {
573 		pr_info("This system has a very crappy BIOS: It doesn't even list the DIMMS.\n");
574 		pr_info("Its SMBIOS info is wrong. It is doubtful that the error report would\n");
575 		pr_info("work on such system. Use this driver with caution\n");
576 	} else if (idx < 0) {
577 		pr_info("This EDAC driver relies on BIOS to enumerate memory and get error reports.\n");
578 		pr_info("Unfortunately, not all BIOSes reflect the memory layout correctly.\n");
579 		pr_info("So, the end result of using this driver varies from vendor to vendor.\n");
580 		pr_info("If you find incorrect reports, please contact your hardware vendor\n");
581 		pr_info("to correct its BIOS.\n");
582 		pr_info("This system has %d DIMM sockets.\n", ghes_hw.num_dimms);
583 	}
584 
585 	if (!fake) {
586 		struct dimm_info *src, *dst;
587 		int i = 0;
588 
589 		mci_for_each_dimm(mci, dst) {
590 			src = &ghes_hw.dimms[i];
591 
592 			dst->idx	   = src->idx;
593 			dst->smbios_handle = src->smbios_handle;
594 			dst->nr_pages	   = src->nr_pages;
595 			dst->mtype	   = src->mtype;
596 			dst->edac_mode	   = src->edac_mode;
597 			dst->dtype	   = src->dtype;
598 			dst->grain	   = src->grain;
599 
600 			/*
601 			 * If no src->label, preserve default label assigned
602 			 * from EDAC core.
603 			 */
604 			if (strlen(src->label))
605 				memcpy(dst->label, src->label, sizeof(src->label));
606 
607 			i++;
608 		}
609 
610 	} else {
611 		struct dimm_info *dimm = edac_get_dimm(mci, 0, 0, 0);
612 
613 		dimm->nr_pages = 1;
614 		dimm->grain = 128;
615 		dimm->mtype = MEM_UNKNOWN;
616 		dimm->dtype = DEV_UNKNOWN;
617 		dimm->edac_mode = EDAC_SECDED;
618 	}
619 
620 	rc = edac_mc_add_mc(mci);
621 	if (rc < 0) {
622 		pr_info("Can't register with the EDAC core\n");
623 		edac_mc_free(mci);
624 		rc = -ENODEV;
625 		goto unlock;
626 	}
627 
628 	spin_lock_irqsave(&ghes_lock, flags);
629 	ghes_pvt = pvt;
630 	spin_unlock_irqrestore(&ghes_lock, flags);
631 
632 	/* only set on success */
633 	refcount_set(&ghes_refcount, 1);
634 
635 unlock:
636 
637 	/* Not needed anymore */
638 	kfree(ghes_hw.dimms);
639 	ghes_hw.dimms = NULL;
640 
641 	mutex_unlock(&ghes_reg_mutex);
642 
643 	return rc;
644 }
645 
ghes_edac_unregister(struct ghes *ghes)646 void ghes_edac_unregister(struct ghes *ghes)
647 {
648 	struct mem_ctl_info *mci;
649 	unsigned long flags;
650 
651 	if (!force_load)
652 		return;
653 
654 	mutex_lock(&ghes_reg_mutex);
655 
656 	system_scanned = false;
657 	memset(&ghes_hw, 0, sizeof(struct ghes_hw_desc));
658 
659 	if (!refcount_dec_and_test(&ghes_refcount))
660 		goto unlock;
661 
662 	/*
663 	 * Wait for the irq handler being finished.
664 	 */
665 	spin_lock_irqsave(&ghes_lock, flags);
666 	mci = ghes_pvt ? ghes_pvt->mci : NULL;
667 	ghes_pvt = NULL;
668 	spin_unlock_irqrestore(&ghes_lock, flags);
669 
670 	if (!mci)
671 		goto unlock;
672 
673 	mci = edac_mc_del_mc(mci->pdev);
674 	if (mci)
675 		edac_mc_free(mci);
676 
677 unlock:
678 	mutex_unlock(&ghes_reg_mutex);
679 }
680