1/*
2 * (C) 2005, 2006 Linux Networx (http://lnxi.com)
3 * This file may be distributed under the terms of the
4 * GNU General Public License.
5 *
6 * Written Doug Thompson <norsk5@xmission.com>
7 *
8 */
9#include <linux/module.h>
10#include <linux/edac.h>
11#include <linux/slab.h>
12#include <linux/ctype.h>
13
14#include "edac_pci.h"
15#include "edac_module.h"
16
17#define EDAC_PCI_SYMLINK	"device"
18
19/* data variables exported via sysfs */
20static int check_pci_errors;		/* default NO check PCI parity */
21static int edac_pci_panic_on_pe;	/* default NO panic on PCI Parity */
22static int edac_pci_log_pe = 1;		/* log PCI parity errors */
23static int edac_pci_log_npe = 1;	/* log PCI non-parity error errors */
24static int edac_pci_poll_msec = 1000;	/* one second workq period */
25
26static atomic_t pci_parity_count = ATOMIC_INIT(0);
27static atomic_t pci_nonparity_count = ATOMIC_INIT(0);
28
29static struct kobject *edac_pci_top_main_kobj;
30static atomic_t edac_pci_sysfs_refcount = ATOMIC_INIT(0);
31
32/* getter functions for the data variables */
33int edac_pci_get_check_errors(void)
34{
35	return check_pci_errors;
36}
37
38static int edac_pci_get_log_pe(void)
39{
40	return edac_pci_log_pe;
41}
42
43static int edac_pci_get_log_npe(void)
44{
45	return edac_pci_log_npe;
46}
47
48static int edac_pci_get_panic_on_pe(void)
49{
50	return edac_pci_panic_on_pe;
51}
52
53int edac_pci_get_poll_msec(void)
54{
55	return edac_pci_poll_msec;
56}
57
58/**************************** EDAC PCI sysfs instance *******************/
59static ssize_t instance_pe_count_show(struct edac_pci_ctl_info *pci, char *data)
60{
61	return sprintf(data, "%u\n", atomic_read(&pci->counters.pe_count));
62}
63
64static ssize_t instance_npe_count_show(struct edac_pci_ctl_info *pci,
65				char *data)
66{
67	return sprintf(data, "%u\n", atomic_read(&pci->counters.npe_count));
68}
69
70#define to_instance(k) container_of(k, struct edac_pci_ctl_info, kobj)
71#define to_instance_attr(a) container_of(a, struct instance_attribute, attr)
72
73/* DEVICE instance kobject release() function */
74static void edac_pci_instance_release(struct kobject *kobj)
75{
76	struct edac_pci_ctl_info *pci;
77
78	edac_dbg(0, "\n");
79
80	/* Form pointer to containing struct, the pci control struct */
81	pci = to_instance(kobj);
82
83	/* decrement reference count on top main kobj */
84	kobject_put(edac_pci_top_main_kobj);
85
86	kfree(pci);	/* Free the control struct */
87}
88
89/* instance specific attribute structure */
90struct instance_attribute {
91	struct attribute attr;
92	ssize_t(*show) (struct edac_pci_ctl_info *, char *);
93	ssize_t(*store) (struct edac_pci_ctl_info *, const char *, size_t);
94};
95
96/* Function to 'show' fields from the edac_pci 'instance' structure */
97static ssize_t edac_pci_instance_show(struct kobject *kobj,
98				struct attribute *attr, char *buffer)
99{
100	struct edac_pci_ctl_info *pci = to_instance(kobj);
101	struct instance_attribute *instance_attr = to_instance_attr(attr);
102
103	if (instance_attr->show)
104		return instance_attr->show(pci, buffer);
105	return -EIO;
106}
107
108/* Function to 'store' fields into the edac_pci 'instance' structure */
109static ssize_t edac_pci_instance_store(struct kobject *kobj,
110				struct attribute *attr,
111				const char *buffer, size_t count)
112{
113	struct edac_pci_ctl_info *pci = to_instance(kobj);
114	struct instance_attribute *instance_attr = to_instance_attr(attr);
115
116	if (instance_attr->store)
117		return instance_attr->store(pci, buffer, count);
118	return -EIO;
119}
120
121/* fs_ops table */
122static const struct sysfs_ops pci_instance_ops = {
123	.show = edac_pci_instance_show,
124	.store = edac_pci_instance_store
125};
126
127#define INSTANCE_ATTR(_name, _mode, _show, _store)	\
128static struct instance_attribute attr_instance_##_name = {	\
129	.attr	= {.name = __stringify(_name), .mode = _mode },	\
130	.show	= _show,					\
131	.store	= _store,					\
132};
133
134INSTANCE_ATTR(pe_count, S_IRUGO, instance_pe_count_show, NULL);
135INSTANCE_ATTR(npe_count, S_IRUGO, instance_npe_count_show, NULL);
136
137/* pci instance attributes */
138static struct instance_attribute *pci_instance_attr[] = {
139	&attr_instance_pe_count,
140	&attr_instance_npe_count,
141	NULL
142};
143
144/* the ktype for a pci instance */
145static struct kobj_type ktype_pci_instance = {
146	.release = edac_pci_instance_release,
147	.sysfs_ops = &pci_instance_ops,
148	.default_attrs = (struct attribute **)pci_instance_attr,
149};
150
151/*
152 * edac_pci_create_instance_kobj
153 *
154 *	construct one EDAC PCI instance's kobject for use
155 */
156static int edac_pci_create_instance_kobj(struct edac_pci_ctl_info *pci, int idx)
157{
158	struct kobject *main_kobj;
159	int err;
160
161	edac_dbg(0, "\n");
162
163	/* First bump the ref count on the top main kobj, which will
164	 * track the number of PCI instances we have, and thus nest
165	 * properly on keeping the module loaded
166	 */
167	main_kobj = kobject_get(edac_pci_top_main_kobj);
168	if (!main_kobj) {
169		err = -ENODEV;
170		goto error_out;
171	}
172
173	/* And now register this new kobject under the main kobj */
174	err = kobject_init_and_add(&pci->kobj, &ktype_pci_instance,
175				   edac_pci_top_main_kobj, "pci%d", idx);
176	if (err != 0) {
177		edac_dbg(2, "failed to register instance pci%d\n", idx);
178		kobject_put(edac_pci_top_main_kobj);
179		goto error_out;
180	}
181
182	kobject_uevent(&pci->kobj, KOBJ_ADD);
183	edac_dbg(1, "Register instance 'pci%d' kobject\n", idx);
184
185	return 0;
186
187	/* Error unwind statck */
188error_out:
189	return err;
190}
191
192/*
193 * edac_pci_unregister_sysfs_instance_kobj
194 *
195 *	unregister the kobj for the EDAC PCI instance
196 */
197static void edac_pci_unregister_sysfs_instance_kobj(
198			struct edac_pci_ctl_info *pci)
199{
200	edac_dbg(0, "\n");
201
202	/* Unregister the instance kobject and allow its release
203	 * function release the main reference count and then
204	 * kfree the memory
205	 */
206	kobject_put(&pci->kobj);
207}
208
209/***************************** EDAC PCI sysfs root **********************/
210#define to_edacpci(k) container_of(k, struct edac_pci_ctl_info, kobj)
211#define to_edacpci_attr(a) container_of(a, struct edac_pci_attr, attr)
212
213/* simple show/store functions for attributes */
214static ssize_t edac_pci_int_show(void *ptr, char *buffer)
215{
216	int *value = ptr;
217	return sprintf(buffer, "%d\n", *value);
218}
219
220static ssize_t edac_pci_int_store(void *ptr, const char *buffer, size_t count)
221{
222	int *value = ptr;
223
224	if (isdigit(*buffer))
225		*value = simple_strtoul(buffer, NULL, 0);
226
227	return count;
228}
229
230struct edac_pci_dev_attribute {
231	struct attribute attr;
232	void *value;
233	 ssize_t(*show) (void *, char *);
234	 ssize_t(*store) (void *, const char *, size_t);
235};
236
237/* Set of show/store abstract level functions for PCI Parity object */
238static ssize_t edac_pci_dev_show(struct kobject *kobj, struct attribute *attr,
239				 char *buffer)
240{
241	struct edac_pci_dev_attribute *edac_pci_dev;
242	edac_pci_dev = (struct edac_pci_dev_attribute *)attr;
243
244	if (edac_pci_dev->show)
245		return edac_pci_dev->show(edac_pci_dev->value, buffer);
246	return -EIO;
247}
248
249static ssize_t edac_pci_dev_store(struct kobject *kobj,
250				struct attribute *attr, const char *buffer,
251				size_t count)
252{
253	struct edac_pci_dev_attribute *edac_pci_dev;
254	edac_pci_dev = (struct edac_pci_dev_attribute *)attr;
255
256	if (edac_pci_dev->store)
257		return edac_pci_dev->store(edac_pci_dev->value, buffer, count);
258	return -EIO;
259}
260
261static const struct sysfs_ops edac_pci_sysfs_ops = {
262	.show = edac_pci_dev_show,
263	.store = edac_pci_dev_store
264};
265
266#define EDAC_PCI_ATTR(_name,_mode,_show,_store)			\
267static struct edac_pci_dev_attribute edac_pci_attr_##_name = {		\
268	.attr = {.name = __stringify(_name), .mode = _mode },	\
269	.value  = &_name,					\
270	.show   = _show,					\
271	.store  = _store,					\
272};
273
274#define EDAC_PCI_STRING_ATTR(_name,_data,_mode,_show,_store)	\
275static struct edac_pci_dev_attribute edac_pci_attr_##_name = {		\
276	.attr = {.name = __stringify(_name), .mode = _mode },	\
277	.value  = _data,					\
278	.show   = _show,					\
279	.store  = _store,					\
280};
281
282/* PCI Parity control files */
283EDAC_PCI_ATTR(check_pci_errors, S_IRUGO | S_IWUSR, edac_pci_int_show,
284	edac_pci_int_store);
285EDAC_PCI_ATTR(edac_pci_log_pe, S_IRUGO | S_IWUSR, edac_pci_int_show,
286	edac_pci_int_store);
287EDAC_PCI_ATTR(edac_pci_log_npe, S_IRUGO | S_IWUSR, edac_pci_int_show,
288	edac_pci_int_store);
289EDAC_PCI_ATTR(edac_pci_panic_on_pe, S_IRUGO | S_IWUSR, edac_pci_int_show,
290	edac_pci_int_store);
291EDAC_PCI_ATTR(pci_parity_count, S_IRUGO, edac_pci_int_show, NULL);
292EDAC_PCI_ATTR(pci_nonparity_count, S_IRUGO, edac_pci_int_show, NULL);
293
294/* Base Attributes of the memory ECC object */
295static struct edac_pci_dev_attribute *edac_pci_attr[] = {
296	&edac_pci_attr_check_pci_errors,
297	&edac_pci_attr_edac_pci_log_pe,
298	&edac_pci_attr_edac_pci_log_npe,
299	&edac_pci_attr_edac_pci_panic_on_pe,
300	&edac_pci_attr_pci_parity_count,
301	&edac_pci_attr_pci_nonparity_count,
302	NULL,
303};
304
305/*
306 * edac_pci_release_main_kobj
307 *
308 *	This release function is called when the reference count to the
309 *	passed kobj goes to zero.
310 *
311 *	This kobj is the 'main' kobject that EDAC PCI instances
312 *	link to, and thus provide for proper nesting counts
313 */
314static void edac_pci_release_main_kobj(struct kobject *kobj)
315{
316	edac_dbg(0, "here to module_put(THIS_MODULE)\n");
317
318	kfree(kobj);
319
320	/* last reference to top EDAC PCI kobject has been removed,
321	 * NOW release our ref count on the core module
322	 */
323	module_put(THIS_MODULE);
324}
325
326/* ktype struct for the EDAC PCI main kobj */
327static struct kobj_type ktype_edac_pci_main_kobj = {
328	.release = edac_pci_release_main_kobj,
329	.sysfs_ops = &edac_pci_sysfs_ops,
330	.default_attrs = (struct attribute **)edac_pci_attr,
331};
332
333/**
334 * edac_pci_main_kobj_setup: Setup the sysfs for EDAC PCI attributes.
335 */
336static int edac_pci_main_kobj_setup(void)
337{
338	int err;
339	struct bus_type *edac_subsys;
340
341	edac_dbg(0, "\n");
342
343	/* check and count if we have already created the main kobject */
344	if (atomic_inc_return(&edac_pci_sysfs_refcount) != 1)
345		return 0;
346
347	/* First time, so create the main kobject and its
348	 * controls and attributes
349	 */
350	edac_subsys = edac_get_sysfs_subsys();
351
352	/* Bump the reference count on this module to ensure the
353	 * modules isn't unloaded until we deconstruct the top
354	 * level main kobj for EDAC PCI
355	 */
356	if (!try_module_get(THIS_MODULE)) {
357		edac_dbg(1, "try_module_get() failed\n");
358		err = -ENODEV;
359		goto decrement_count_fail;
360	}
361
362	edac_pci_top_main_kobj = kzalloc(sizeof(struct kobject), GFP_KERNEL);
363	if (!edac_pci_top_main_kobj) {
364		edac_dbg(1, "Failed to allocate\n");
365		err = -ENOMEM;
366		goto kzalloc_fail;
367	}
368
369	/* Instanstiate the pci object */
370	err = kobject_init_and_add(edac_pci_top_main_kobj,
371				   &ktype_edac_pci_main_kobj,
372				   &edac_subsys->dev_root->kobj, "pci");
373	if (err) {
374		edac_dbg(1, "Failed to register '.../edac/pci'\n");
375		goto kobject_init_and_add_fail;
376	}
377
378	/* At this point, to 'release' the top level kobject
379	 * for EDAC PCI, then edac_pci_main_kobj_teardown()
380	 * must be used, for resources to be cleaned up properly
381	 */
382	kobject_uevent(edac_pci_top_main_kobj, KOBJ_ADD);
383	edac_dbg(1, "Registered '.../edac/pci' kobject\n");
384
385	return 0;
386
387	/* Error unwind statck */
388kobject_init_and_add_fail:
389	kobject_put(edac_pci_top_main_kobj);
390
391kzalloc_fail:
392	module_put(THIS_MODULE);
393
394decrement_count_fail:
395	/* if are on this error exit, nothing to tear down */
396	atomic_dec(&edac_pci_sysfs_refcount);
397
398	return err;
399}
400
401/*
402 * edac_pci_main_kobj_teardown()
403 *
404 *	if no longer linked (needed) remove the top level EDAC PCI
405 *	kobject with its controls and attributes
406 */
407static void edac_pci_main_kobj_teardown(void)
408{
409	edac_dbg(0, "\n");
410
411	/* Decrement the count and only if no more controller instances
412	 * are connected perform the unregisteration of the top level
413	 * main kobj
414	 */
415	if (atomic_dec_return(&edac_pci_sysfs_refcount) == 0) {
416		edac_dbg(0, "called kobject_put on main kobj\n");
417		kobject_put(edac_pci_top_main_kobj);
418	}
419}
420
421int edac_pci_create_sysfs(struct edac_pci_ctl_info *pci)
422{
423	int err;
424	struct kobject *edac_kobj = &pci->kobj;
425
426	edac_dbg(0, "idx=%d\n", pci->pci_idx);
427
428	/* create the top main EDAC PCI kobject, IF needed */
429	err = edac_pci_main_kobj_setup();
430	if (err)
431		return err;
432
433	/* Create this instance's kobject under the MAIN kobject */
434	err = edac_pci_create_instance_kobj(pci, pci->pci_idx);
435	if (err)
436		goto unregister_cleanup;
437
438	err = sysfs_create_link(edac_kobj, &pci->dev->kobj, EDAC_PCI_SYMLINK);
439	if (err) {
440		edac_dbg(0, "sysfs_create_link() returned err= %d\n", err);
441		goto symlink_fail;
442	}
443
444	return 0;
445
446	/* Error unwind stack */
447symlink_fail:
448	edac_pci_unregister_sysfs_instance_kobj(pci);
449
450unregister_cleanup:
451	edac_pci_main_kobj_teardown();
452
453	return err;
454}
455
456void edac_pci_remove_sysfs(struct edac_pci_ctl_info *pci)
457{
458	edac_dbg(0, "index=%d\n", pci->pci_idx);
459
460	/* Remove the symlink */
461	sysfs_remove_link(&pci->kobj, EDAC_PCI_SYMLINK);
462
463	/* remove this PCI instance's sysfs entries */
464	edac_pci_unregister_sysfs_instance_kobj(pci);
465
466	/* Call the main unregister function, which will determine
467	 * if this 'pci' is the last instance.
468	 * If it is, the main kobject will be unregistered as a result
469	 */
470	edac_dbg(0, "calling edac_pci_main_kobj_teardown()\n");
471	edac_pci_main_kobj_teardown();
472}
473
474/************************ PCI error handling *************************/
475static u16 get_pci_parity_status(struct pci_dev *dev, int secondary)
476{
477	int where;
478	u16 status;
479
480	where = secondary ? PCI_SEC_STATUS : PCI_STATUS;
481	pci_read_config_word(dev, where, &status);
482
483	/* If we get back 0xFFFF then we must suspect that the card has been
484	 * pulled but the Linux PCI layer has not yet finished cleaning up.
485	 * We don't want to report on such devices
486	 */
487
488	if (status == 0xFFFF) {
489		u32 sanity;
490
491		pci_read_config_dword(dev, 0, &sanity);
492
493		if (sanity == 0xFFFFFFFF)
494			return 0;
495	}
496
497	status &= PCI_STATUS_DETECTED_PARITY | PCI_STATUS_SIG_SYSTEM_ERROR |
498		PCI_STATUS_PARITY;
499
500	if (status)
501		/* reset only the bits we are interested in */
502		pci_write_config_word(dev, where, status);
503
504	return status;
505}
506
507
508/* Clear any PCI parity errors logged by this device. */
509static void edac_pci_dev_parity_clear(struct pci_dev *dev)
510{
511	u8 header_type;
512
513	get_pci_parity_status(dev, 0);
514
515	/* read the device TYPE, looking for bridges */
516	pci_read_config_byte(dev, PCI_HEADER_TYPE, &header_type);
517
518	if ((header_type & 0x7F) == PCI_HEADER_TYPE_BRIDGE)
519		get_pci_parity_status(dev, 1);
520}
521
522/*
523 *  PCI Parity polling
524 *
525 *	Function to retrieve the current parity status
526 *	and decode it
527 *
528 */
529static void edac_pci_dev_parity_test(struct pci_dev *dev)
530{
531	unsigned long flags;
532	u16 status;
533	u8 header_type;
534
535	/* stop any interrupts until we can acquire the status */
536	local_irq_save(flags);
537
538	/* read the STATUS register on this device */
539	status = get_pci_parity_status(dev, 0);
540
541	/* read the device TYPE, looking for bridges */
542	pci_read_config_byte(dev, PCI_HEADER_TYPE, &header_type);
543
544	local_irq_restore(flags);
545
546	edac_dbg(4, "PCI STATUS= 0x%04x %s\n", status, dev_name(&dev->dev));
547
548	/* check the status reg for errors on boards NOT marked as broken
549	 * if broken, we cannot trust any of the status bits
550	 */
551	if (status && !dev->broken_parity_status) {
552		if (status & (PCI_STATUS_SIG_SYSTEM_ERROR)) {
553			edac_printk(KERN_CRIT, EDAC_PCI,
554				"Signaled System Error on %s\n",
555				pci_name(dev));
556			atomic_inc(&pci_nonparity_count);
557		}
558
559		if (status & (PCI_STATUS_PARITY)) {
560			edac_printk(KERN_CRIT, EDAC_PCI,
561				"Master Data Parity Error on %s\n",
562				pci_name(dev));
563
564			atomic_inc(&pci_parity_count);
565		}
566
567		if (status & (PCI_STATUS_DETECTED_PARITY)) {
568			edac_printk(KERN_CRIT, EDAC_PCI,
569				"Detected Parity Error on %s\n",
570				pci_name(dev));
571
572			atomic_inc(&pci_parity_count);
573		}
574	}
575
576
577	edac_dbg(4, "PCI HEADER TYPE= 0x%02x %s\n",
578		 header_type, dev_name(&dev->dev));
579
580	if ((header_type & 0x7F) == PCI_HEADER_TYPE_BRIDGE) {
581		/* On bridges, need to examine secondary status register  */
582		status = get_pci_parity_status(dev, 1);
583
584		edac_dbg(4, "PCI SEC_STATUS= 0x%04x %s\n",
585			 status, dev_name(&dev->dev));
586
587		/* check the secondary status reg for errors,
588		 * on NOT broken boards
589		 */
590		if (status && !dev->broken_parity_status) {
591			if (status & (PCI_STATUS_SIG_SYSTEM_ERROR)) {
592				edac_printk(KERN_CRIT, EDAC_PCI, "Bridge "
593					"Signaled System Error on %s\n",
594					pci_name(dev));
595				atomic_inc(&pci_nonparity_count);
596			}
597
598			if (status & (PCI_STATUS_PARITY)) {
599				edac_printk(KERN_CRIT, EDAC_PCI, "Bridge "
600					"Master Data Parity Error on "
601					"%s\n", pci_name(dev));
602
603				atomic_inc(&pci_parity_count);
604			}
605
606			if (status & (PCI_STATUS_DETECTED_PARITY)) {
607				edac_printk(KERN_CRIT, EDAC_PCI, "Bridge "
608					"Detected Parity Error on %s\n",
609					pci_name(dev));
610
611				atomic_inc(&pci_parity_count);
612			}
613		}
614	}
615}
616
617/* reduce some complexity in definition of the iterator */
618typedef void (*pci_parity_check_fn_t) (struct pci_dev *dev);
619
620/*
621 * pci_dev parity list iterator
622 *
623 *	Scan the PCI device list looking for SERRORs, Master Parity ERRORS or
624 *	Parity ERRORs on primary or secondary devices.
625 */
626static inline void edac_pci_dev_parity_iterator(pci_parity_check_fn_t fn)
627{
628	struct pci_dev *dev = NULL;
629
630	for_each_pci_dev(dev)
631		fn(dev);
632}
633
634/*
635 * edac_pci_do_parity_check
636 *
637 *	performs the actual PCI parity check operation
638 */
639void edac_pci_do_parity_check(void)
640{
641	int before_count;
642
643	edac_dbg(3, "\n");
644
645	/* if policy has PCI check off, leave now */
646	if (!check_pci_errors)
647		return;
648
649	before_count = atomic_read(&pci_parity_count);
650
651	/* scan all PCI devices looking for a Parity Error on devices and
652	 * bridges.
653	 * The iterator calls pci_get_device() which might sleep, thus
654	 * we cannot disable interrupts in this scan.
655	 */
656	edac_pci_dev_parity_iterator(edac_pci_dev_parity_test);
657
658	/* Only if operator has selected panic on PCI Error */
659	if (edac_pci_get_panic_on_pe()) {
660		/* If the count is different 'after' from 'before' */
661		if (before_count != atomic_read(&pci_parity_count))
662			panic("EDAC: PCI Parity Error");
663	}
664}
665
666/*
667 * edac_pci_clear_parity_errors
668 *
669 *	function to perform an iteration over the PCI devices
670 *	and clearn their current status
671 */
672void edac_pci_clear_parity_errors(void)
673{
674	/* Clear any PCI bus parity errors that devices initially have logged
675	 * in their registers.
676	 */
677	edac_pci_dev_parity_iterator(edac_pci_dev_parity_clear);
678}
679
680/*
681 * edac_pci_handle_pe
682 *
683 *	Called to handle a PARITY ERROR event
684 */
685void edac_pci_handle_pe(struct edac_pci_ctl_info *pci, const char *msg)
686{
687
688	/* global PE counter incremented by edac_pci_do_parity_check() */
689	atomic_inc(&pci->counters.pe_count);
690
691	if (edac_pci_get_log_pe())
692		edac_pci_printk(pci, KERN_WARNING,
693				"Parity Error ctl: %s %d: %s\n",
694				pci->ctl_name, pci->pci_idx, msg);
695
696	/*
697	 * poke all PCI devices and see which one is the troublemaker
698	 * panic() is called if set
699	 */
700	edac_pci_do_parity_check();
701}
702EXPORT_SYMBOL_GPL(edac_pci_handle_pe);
703
704
705/*
706 * edac_pci_handle_npe
707 *
708 *	Called to handle a NON-PARITY ERROR event
709 */
710void edac_pci_handle_npe(struct edac_pci_ctl_info *pci, const char *msg)
711{
712
713	/* global NPE counter incremented by edac_pci_do_parity_check() */
714	atomic_inc(&pci->counters.npe_count);
715
716	if (edac_pci_get_log_npe())
717		edac_pci_printk(pci, KERN_WARNING,
718				"Non-Parity Error ctl: %s %d: %s\n",
719				pci->ctl_name, pci->pci_idx, msg);
720
721	/*
722	 * poke all PCI devices and see which one is the troublemaker
723	 * panic() is called if set
724	 */
725	edac_pci_do_parity_check();
726}
727EXPORT_SYMBOL_GPL(edac_pci_handle_npe);
728
729/*
730 * Define the PCI parameter to the module
731 */
732module_param(check_pci_errors, int, 0644);
733MODULE_PARM_DESC(check_pci_errors,
734		 "Check for PCI bus parity errors: 0=off 1=on");
735module_param(edac_pci_panic_on_pe, int, 0644);
736MODULE_PARM_DESC(edac_pci_panic_on_pe,
737		 "Panic on PCI Bus Parity error: 0=off 1=on");
738