acpi_extlog.c

  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Extended Error Log driver
  4 *
  5 * Copyright (C) 2013 Intel Corp.
  6 * Author: Chen, Gong <gong.chen@intel.com>
  7 */
  8
  9#include <linux/module.h>
 10#include <linux/acpi.h>
 11#include <linux/cper.h>
 12#include <linux/ratelimit.h>
 13#include <linux/edac.h>
 14#include <linux/ras.h>
 15#include <acpi/ghes.h>
 16#include <asm/cpu.h>
 17#include <asm/mce.h>
 18#include <asm/msr.h>
 19
 20#include "apei/apei-internal.h"
 21#include <ras/ras_event.h>
 22
 23#define EXT_ELOG_ENTRY_MASK	GENMASK_ULL(51, 0) /* elog entry address mask */
 24
 25#define EXTLOG_DSM_REV		0x0
 26#define	EXTLOG_FN_ADDR		0x1
 27
 28#define FLAG_OS_OPTIN		BIT(0)
 29#define ELOG_ENTRY_VALID	(1ULL<<63)
 30#define ELOG_ENTRY_LEN		0x1000
 31
 32#define EMCA_BUG \
 33	"Can not request iomem region <0x%016llx-0x%016llx> - eMCA disabled\n"
 34
 35struct extlog_l1_head {
 36	u32 ver;	/* Header Version */
 37	u32 hdr_len;	/* Header Length */
 38	u64 total_len;	/* entire L1 Directory length including this header */
 39	u64 elog_base;	/* MCA Error Log Directory base address */
 40	u64 elog_len;	/* MCA Error Log Directory length */
 41	u32 flags;	/* bit 0 - OS/VMM Opt-in */
 42	u8  rev0[12];
 43	u32 entries;	/* Valid L1 Directory entries per logical processor */
 44	u8  rev1[12];
 45};
 46
 47static u8 extlog_dsm_uuid[] __initdata = "663E35AF-CC10-41A4-88EA-5470AF055295";
 48
 49/* L1 table related physical address */
 50static u64 elog_base;
 51static size_t elog_size;
 52static u64 l1_dirbase;
 53static size_t l1_size;
 54
 55/* L1 table related virtual address */
 56static void __iomem *extlog_l1_addr;
 57static void __iomem *elog_addr;
 58
 59static void *elog_buf;
 60
 61static u64 *l1_entry_base;
 62static u32 l1_percpu_entry;
 63
 64#define ELOG_IDX(cpu, bank) \
 65	(cpu_physical_id(cpu) * l1_percpu_entry + (bank))
 66
 67#define ELOG_ENTRY_DATA(idx) \
 68	(*(l1_entry_base + (idx)))
 69
 70#define ELOG_ENTRY_ADDR(phyaddr) \
 71	(phyaddr - elog_base + (u8 *)elog_addr)
 72
 73static struct acpi_hest_generic_status *extlog_elog_entry_check(int cpu, int bank)
 74{
 75	int idx;
 76	u64 data;
 77	struct acpi_hest_generic_status *estatus;
 78
 79	WARN_ON(cpu < 0);
 80	idx = ELOG_IDX(cpu, bank);
 81	data = ELOG_ENTRY_DATA(idx);
 82	if ((data & ELOG_ENTRY_VALID) == 0)
 83		return NULL;
 84
 85	data &= EXT_ELOG_ENTRY_MASK;
 86	estatus = (struct acpi_hest_generic_status *)ELOG_ENTRY_ADDR(data);
 87
 88	/* if no valid data in elog entry, just return */
 89	if (estatus->block_status == 0)
 90		return NULL;
 91
 92	return estatus;
 93}
 94
 95static void __print_extlog_rcd(const char *pfx,
 96			       struct acpi_hest_generic_status *estatus, int cpu)
 97{
 98	static atomic_t seqno;
 99	unsigned int curr_seqno;
100	char pfx_seq[64];
101
102	if (!pfx) {
103		if (estatus->error_severity <= CPER_SEV_CORRECTED)
104			pfx = KERN_INFO;
105		else
106			pfx = KERN_ERR;
107	}
108	curr_seqno = atomic_inc_return(&seqno);
109	snprintf(pfx_seq, sizeof(pfx_seq), "%s{%u}", pfx, curr_seqno);
110	printk("%s""Hardware error detected on CPU%d\n", pfx_seq, cpu);
111	cper_estatus_print(pfx_seq, estatus);
112}
113
114static int print_extlog_rcd(const char *pfx,
115			    struct acpi_hest_generic_status *estatus, int cpu)
116{
117	/* Not more than 2 messages every 5 seconds */
118	static DEFINE_RATELIMIT_STATE(ratelimit_corrected, 5*HZ, 2);
119	static DEFINE_RATELIMIT_STATE(ratelimit_uncorrected, 5*HZ, 2);
120	struct ratelimit_state *ratelimit;
121
122	if (estatus->error_severity == CPER_SEV_CORRECTED ||
123	    (estatus->error_severity == CPER_SEV_INFORMATIONAL))
124		ratelimit = &ratelimit_corrected;
125	else
126		ratelimit = &ratelimit_uncorrected;
127	if (__ratelimit(ratelimit)) {
128		__print_extlog_rcd(pfx, estatus, cpu);
129		return 0;
130	}
131
132	return 1;
133}
134
135static int extlog_print(struct notifier_block *nb, unsigned long val,
136			void *data)
137{
138	struct mce *mce = (struct mce *)data;
139	int	bank = mce->bank;
140	int	cpu = mce->extcpu;
141	struct acpi_hest_generic_status *estatus, *tmp;
142	struct acpi_hest_generic_data *gdata;
143	const guid_t *fru_id;
144	char *fru_text;
145	guid_t *sec_type;
146	static u32 err_seq;
147
148	estatus = extlog_elog_entry_check(cpu, bank);
149	if (!estatus)
150		return NOTIFY_DONE;
151
152	if (mce->kflags & MCE_HANDLED_CEC) {
153		estatus->block_status = 0;
154		return NOTIFY_DONE;
155	}
156
157	memcpy(elog_buf, (void *)estatus, ELOG_ENTRY_LEN);
158	/* clear record status to enable BIOS to update it again */
159	estatus->block_status = 0;
160
161	tmp = (struct acpi_hest_generic_status *)elog_buf;
162
163	if (!ras_userspace_consumers()) {
164		print_extlog_rcd(NULL, tmp, cpu);
165		goto out;
166	}
167
168	/* log event via trace */
169	err_seq++;
170	apei_estatus_for_each_section(tmp, gdata) {
171		if (gdata->validation_bits & CPER_SEC_VALID_FRU_ID)
172			fru_id = (guid_t *)gdata->fru_id;
173		else
174			fru_id = &guid_null;
175		if (gdata->validation_bits & CPER_SEC_VALID_FRU_TEXT)
176			fru_text = gdata->fru_text;
177		else
178			fru_text = "";
179		sec_type = (guid_t *)gdata->section_type;
180		if (guid_equal(sec_type, &CPER_SEC_PLATFORM_MEM)) {
181			struct cper_sec_mem_err *mem = acpi_hest_get_payload(gdata);
182
183			if (gdata->error_data_length >= sizeof(*mem))
184				trace_extlog_mem_event(mem, err_seq, fru_id, fru_text,
185						       (u8)gdata->error_severity);
186		}
187	}
188
189out:
190	mce->kflags |= MCE_HANDLED_EXTLOG;
191	return NOTIFY_OK;
192}
193
194static bool __init extlog_get_l1addr(void)
195{
196	guid_t guid;
197	acpi_handle handle;
198	union acpi_object *obj;
199
200	if (guid_parse(extlog_dsm_uuid, &guid))
201		return false;
202	if (ACPI_FAILURE(acpi_get_handle(NULL, "\\_SB", &handle)))
203		return false;
204	if (!acpi_check_dsm(handle, &guid, EXTLOG_DSM_REV, 1 << EXTLOG_FN_ADDR))
205		return false;
206	obj = acpi_evaluate_dsm_typed(handle, &guid, EXTLOG_DSM_REV,
207				      EXTLOG_FN_ADDR, NULL, ACPI_TYPE_INTEGER);
208	if (!obj) {
209		return false;
210	} else {
211		l1_dirbase = obj->integer.value;
212		ACPI_FREE(obj);
213	}
214
215	/* Spec says L1 directory must be 4K aligned, bail out if it isn't */
216	if (l1_dirbase & ((1 << 12) - 1)) {
217		pr_warn(FW_BUG "L1 Directory is invalid at physical %llx\n",
218			l1_dirbase);
219		return false;
220	}
221
222	return true;
223}
224static struct notifier_block extlog_mce_dec = {
225	.notifier_call	= extlog_print,
226	.priority	= MCE_PRIO_EXTLOG,
227};
228
229static int __init extlog_init(void)
230{
231	struct extlog_l1_head *l1_head;
232	void __iomem *extlog_l1_hdr;
233	size_t l1_hdr_size;
234	struct resource *r;
235	u64 cap;
236	int rc;
237
238	if (rdmsrq_safe(MSR_IA32_MCG_CAP, &cap) ||
239	    !(cap & MCG_ELOG_P) ||
240	    !extlog_get_l1addr())
241		return -ENODEV;
242
243	rc = -EINVAL;
244	/* get L1 header to fetch necessary information */
245	l1_hdr_size = sizeof(struct extlog_l1_head);
246	r = request_mem_region(l1_dirbase, l1_hdr_size, "L1 DIR HDR");
247	if (!r) {
248		pr_warn(FW_BUG EMCA_BUG,
249			(unsigned long long)l1_dirbase,
250			(unsigned long long)l1_dirbase + l1_hdr_size);
251		goto err;
252	}
253
254	extlog_l1_hdr = acpi_os_map_iomem(l1_dirbase, l1_hdr_size);
255	if (!extlog_l1_hdr) {
256		rc = -ENOMEM;
257		goto err_release_l1_hdr;
258	}
259	l1_head = (struct extlog_l1_head *)extlog_l1_hdr;
260	l1_size = l1_head->total_len;
261	l1_percpu_entry = l1_head->entries;
262	elog_base = l1_head->elog_base;
263	elog_size = l1_head->elog_len;
264	acpi_os_unmap_iomem(extlog_l1_hdr, l1_hdr_size);
265	release_mem_region(l1_dirbase, l1_hdr_size);
266
267	/* remap L1 header again based on completed information */
268	r = request_mem_region(l1_dirbase, l1_size, "L1 Table");
269	if (!r) {
270		pr_warn(FW_BUG EMCA_BUG,
271			(unsigned long long)l1_dirbase,
272			(unsigned long long)l1_dirbase + l1_size);
273		goto err;
274	}
275	extlog_l1_addr = acpi_os_map_iomem(l1_dirbase, l1_size);
276	if (!extlog_l1_addr) {
277		rc = -ENOMEM;
278		goto err_release_l1_dir;
279	}
280	l1_entry_base = (u64 *)((u8 *)extlog_l1_addr + l1_hdr_size);
281
282	/* remap elog table */
283	r = request_mem_region(elog_base, elog_size, "Elog Table");
284	if (!r) {
285		pr_warn(FW_BUG EMCA_BUG,
286			(unsigned long long)elog_base,
287			(unsigned long long)elog_base + elog_size);
288		goto err_release_l1_dir;
289	}
290	elog_addr = acpi_os_map_iomem(elog_base, elog_size);
291	if (!elog_addr) {
292		rc = -ENOMEM;
293		goto err_release_elog;
294	}
295
296	rc = -ENOMEM;
297	/* allocate buffer to save elog record */
298	elog_buf = kmalloc(ELOG_ENTRY_LEN, GFP_KERNEL);
299	if (elog_buf == NULL)
300		goto err_release_elog;
301
302	mce_register_decode_chain(&extlog_mce_dec);
303	/* enable OS to be involved to take over management from BIOS */
304	((struct extlog_l1_head *)extlog_l1_addr)->flags |= FLAG_OS_OPTIN;
305
306	return 0;
307
308err_release_elog:
309	if (elog_addr)
310		acpi_os_unmap_iomem(elog_addr, elog_size);
311	release_mem_region(elog_base, elog_size);
312err_release_l1_dir:
313	if (extlog_l1_addr)
314		acpi_os_unmap_iomem(extlog_l1_addr, l1_size);
315	release_mem_region(l1_dirbase, l1_size);
316err_release_l1_hdr:
317	release_mem_region(l1_dirbase, l1_hdr_size);
318err:
319	pr_warn(FW_BUG "Extended error log disabled because of problems parsing f/w tables\n");
320	return rc;
321}
322
323static void __exit extlog_exit(void)
324{
325	mce_unregister_decode_chain(&extlog_mce_dec);
326	if (extlog_l1_addr) {
327		((struct extlog_l1_head *)extlog_l1_addr)->flags &= ~FLAG_OS_OPTIN;
328		acpi_os_unmap_iomem(extlog_l1_addr, l1_size);
329	}
330	if (elog_addr)
331		acpi_os_unmap_iomem(elog_addr, elog_size);
332	release_mem_region(elog_base, elog_size);
333	release_mem_region(l1_dirbase, l1_size);
334	kfree(elog_buf);
335}
336
337module_init(extlog_init);
338module_exit(extlog_exit);
339
340MODULE_AUTHOR("Chen, Gong <gong.chen@intel.com>");
341MODULE_DESCRIPTION("Extended MCA Error Log Driver");
342MODULE_LICENSE("GPL");