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v5.9
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * APEI Generic Hardware Error Source support
   4 *
   5 * Generic Hardware Error Source provides a way to report platform
   6 * hardware errors (such as that from chipset). It works in so called
   7 * "Firmware First" mode, that is, hardware errors are reported to
   8 * firmware firstly, then reported to Linux by firmware. This way,
   9 * some non-standard hardware error registers or non-standard hardware
  10 * link can be checked by firmware to produce more hardware error
  11 * information for Linux.
  12 *
  13 * For more information about Generic Hardware Error Source, please
  14 * refer to ACPI Specification version 4.0, section 17.3.2.6
  15 *
  16 * Copyright 2010,2011 Intel Corp.
  17 *   Author: Huang Ying <ying.huang@intel.com>
  18 */
  19
  20#include <linux/arm_sdei.h>
  21#include <linux/kernel.h>
  22#include <linux/moduleparam.h>
  23#include <linux/init.h>
  24#include <linux/acpi.h>
  25#include <linux/io.h>
  26#include <linux/interrupt.h>
  27#include <linux/timer.h>
  28#include <linux/cper.h>
  29#include <linux/platform_device.h>
  30#include <linux/mutex.h>
  31#include <linux/ratelimit.h>
  32#include <linux/vmalloc.h>
  33#include <linux/irq_work.h>
  34#include <linux/llist.h>
  35#include <linux/genalloc.h>
  36#include <linux/pci.h>
  37#include <linux/pfn.h>
  38#include <linux/aer.h>
  39#include <linux/nmi.h>
  40#include <linux/sched/clock.h>
  41#include <linux/uuid.h>
  42#include <linux/ras.h>
  43#include <linux/task_work.h>
  44
  45#include <acpi/actbl1.h>
  46#include <acpi/ghes.h>
  47#include <acpi/apei.h>
  48#include <asm/fixmap.h>
  49#include <asm/tlbflush.h>
  50#include <ras/ras_event.h>
  51
  52#include "apei-internal.h"
  53
  54#define GHES_PFX	"GHES: "
  55
  56#define GHES_ESTATUS_MAX_SIZE		65536
  57#define GHES_ESOURCE_PREALLOC_MAX_SIZE	65536
  58
  59#define GHES_ESTATUS_POOL_MIN_ALLOC_ORDER 3
  60
  61/* This is just an estimation for memory pool allocation */
  62#define GHES_ESTATUS_CACHE_AVG_SIZE	512
  63
  64#define GHES_ESTATUS_CACHES_SIZE	4
  65
  66#define GHES_ESTATUS_IN_CACHE_MAX_NSEC	10000000000ULL
  67/* Prevent too many caches are allocated because of RCU */
  68#define GHES_ESTATUS_CACHE_ALLOCED_MAX	(GHES_ESTATUS_CACHES_SIZE * 3 / 2)
  69
  70#define GHES_ESTATUS_CACHE_LEN(estatus_len)			\
  71	(sizeof(struct ghes_estatus_cache) + (estatus_len))
  72#define GHES_ESTATUS_FROM_CACHE(estatus_cache)			\
  73	((struct acpi_hest_generic_status *)				\
  74	 ((struct ghes_estatus_cache *)(estatus_cache) + 1))
  75
  76#define GHES_ESTATUS_NODE_LEN(estatus_len)			\
  77	(sizeof(struct ghes_estatus_node) + (estatus_len))
  78#define GHES_ESTATUS_FROM_NODE(estatus_node)			\
  79	((struct acpi_hest_generic_status *)				\
  80	 ((struct ghes_estatus_node *)(estatus_node) + 1))
  81
 
 
 
 
 
 
  82/*
  83 *  NMI-like notifications vary by architecture, before the compiler can prune
  84 *  unused static functions it needs a value for these enums.
  85 */
  86#ifndef CONFIG_ARM_SDE_INTERFACE
  87#define FIX_APEI_GHES_SDEI_NORMAL	__end_of_fixed_addresses
  88#define FIX_APEI_GHES_SDEI_CRITICAL	__end_of_fixed_addresses
  89#endif
  90
 
 
  91static inline bool is_hest_type_generic_v2(struct ghes *ghes)
  92{
  93	return ghes->generic->header.type == ACPI_HEST_TYPE_GENERIC_ERROR_V2;
  94}
  95
  96/*
  97 * This driver isn't really modular, however for the time being,
  98 * continuing to use module_param is the easiest way to remain
  99 * compatible with existing boot arg use cases.
 100 */
 101bool ghes_disable;
 102module_param_named(disable, ghes_disable, bool, 0);
 103
 104/*
 
 
 
 
 
 
 
 105 * All error sources notified with HED (Hardware Error Device) share a
 106 * single notifier callback, so they need to be linked and checked one
 107 * by one. This holds true for NMI too.
 108 *
 109 * RCU is used for these lists, so ghes_list_mutex is only used for
 110 * list changing, not for traversing.
 111 */
 112static LIST_HEAD(ghes_hed);
 113static DEFINE_MUTEX(ghes_list_mutex);
 114
 115/*
 
 
 
 
 
 
 
 116 * Because the memory area used to transfer hardware error information
 117 * from BIOS to Linux can be determined only in NMI, IRQ or timer
 118 * handler, but general ioremap can not be used in atomic context, so
 119 * the fixmap is used instead.
 120 *
 121 * This spinlock is used to prevent the fixmap entry from being used
 122 * simultaneously.
 123 */
 124static DEFINE_SPINLOCK(ghes_notify_lock_irq);
 125
 
 
 
 
 
 
 126static struct gen_pool *ghes_estatus_pool;
 127static unsigned long ghes_estatus_pool_size_request;
 128
 129static struct ghes_estatus_cache *ghes_estatus_caches[GHES_ESTATUS_CACHES_SIZE];
 130static atomic_t ghes_estatus_cache_alloced;
 131
 132static int ghes_panic_timeout __read_mostly = 30;
 133
 134static void __iomem *ghes_map(u64 pfn, enum fixed_addresses fixmap_idx)
 135{
 136	phys_addr_t paddr;
 137	pgprot_t prot;
 138
 139	paddr = PFN_PHYS(pfn);
 140	prot = arch_apei_get_mem_attribute(paddr);
 141	__set_fixmap(fixmap_idx, paddr, prot);
 142
 143	return (void __iomem *) __fix_to_virt(fixmap_idx);
 144}
 145
 146static void ghes_unmap(void __iomem *vaddr, enum fixed_addresses fixmap_idx)
 147{
 148	int _idx = virt_to_fix((unsigned long)vaddr);
 149
 150	WARN_ON_ONCE(fixmap_idx != _idx);
 151	clear_fixmap(fixmap_idx);
 152}
 153
 154int ghes_estatus_pool_init(int num_ghes)
 155{
 156	unsigned long addr, len;
 157	int rc;
 158
 159	ghes_estatus_pool = gen_pool_create(GHES_ESTATUS_POOL_MIN_ALLOC_ORDER, -1);
 160	if (!ghes_estatus_pool)
 161		return -ENOMEM;
 162
 163	len = GHES_ESTATUS_CACHE_AVG_SIZE * GHES_ESTATUS_CACHE_ALLOCED_MAX;
 164	len += (num_ghes * GHES_ESOURCE_PREALLOC_MAX_SIZE);
 165
 166	ghes_estatus_pool_size_request = PAGE_ALIGN(len);
 167	addr = (unsigned long)vmalloc(PAGE_ALIGN(len));
 168	if (!addr)
 169		goto err_pool_alloc;
 170
 171	rc = gen_pool_add(ghes_estatus_pool, addr, PAGE_ALIGN(len), -1);
 172	if (rc)
 173		goto err_pool_add;
 174
 175	return 0;
 176
 177err_pool_add:
 178	vfree((void *)addr);
 179
 180err_pool_alloc:
 181	gen_pool_destroy(ghes_estatus_pool);
 182
 183	return -ENOMEM;
 184}
 185
 186static int map_gen_v2(struct ghes *ghes)
 187{
 188	return apei_map_generic_address(&ghes->generic_v2->read_ack_register);
 189}
 190
 191static void unmap_gen_v2(struct ghes *ghes)
 192{
 193	apei_unmap_generic_address(&ghes->generic_v2->read_ack_register);
 194}
 195
 196static void ghes_ack_error(struct acpi_hest_generic_v2 *gv2)
 197{
 198	int rc;
 199	u64 val = 0;
 200
 201	rc = apei_read(&val, &gv2->read_ack_register);
 202	if (rc)
 203		return;
 204
 205	val &= gv2->read_ack_preserve << gv2->read_ack_register.bit_offset;
 206	val |= gv2->read_ack_write    << gv2->read_ack_register.bit_offset;
 207
 208	apei_write(val, &gv2->read_ack_register);
 209}
 210
 211static struct ghes *ghes_new(struct acpi_hest_generic *generic)
 212{
 213	struct ghes *ghes;
 214	unsigned int error_block_length;
 215	int rc;
 216
 217	ghes = kzalloc(sizeof(*ghes), GFP_KERNEL);
 218	if (!ghes)
 219		return ERR_PTR(-ENOMEM);
 220
 221	ghes->generic = generic;
 222	if (is_hest_type_generic_v2(ghes)) {
 223		rc = map_gen_v2(ghes);
 224		if (rc)
 225			goto err_free;
 226	}
 227
 228	rc = apei_map_generic_address(&generic->error_status_address);
 229	if (rc)
 230		goto err_unmap_read_ack_addr;
 231	error_block_length = generic->error_block_length;
 232	if (error_block_length > GHES_ESTATUS_MAX_SIZE) {
 233		pr_warn(FW_WARN GHES_PFX
 234			"Error status block length is too long: %u for "
 235			"generic hardware error source: %d.\n",
 236			error_block_length, generic->header.source_id);
 237		error_block_length = GHES_ESTATUS_MAX_SIZE;
 238	}
 239	ghes->estatus = kmalloc(error_block_length, GFP_KERNEL);
 240	if (!ghes->estatus) {
 241		rc = -ENOMEM;
 242		goto err_unmap_status_addr;
 243	}
 244
 245	return ghes;
 246
 247err_unmap_status_addr:
 248	apei_unmap_generic_address(&generic->error_status_address);
 249err_unmap_read_ack_addr:
 250	if (is_hest_type_generic_v2(ghes))
 251		unmap_gen_v2(ghes);
 252err_free:
 253	kfree(ghes);
 254	return ERR_PTR(rc);
 255}
 256
 257static void ghes_fini(struct ghes *ghes)
 258{
 259	kfree(ghes->estatus);
 260	apei_unmap_generic_address(&ghes->generic->error_status_address);
 261	if (is_hest_type_generic_v2(ghes))
 262		unmap_gen_v2(ghes);
 263}
 264
 265static inline int ghes_severity(int severity)
 266{
 267	switch (severity) {
 268	case CPER_SEV_INFORMATIONAL:
 269		return GHES_SEV_NO;
 270	case CPER_SEV_CORRECTED:
 271		return GHES_SEV_CORRECTED;
 272	case CPER_SEV_RECOVERABLE:
 273		return GHES_SEV_RECOVERABLE;
 274	case CPER_SEV_FATAL:
 275		return GHES_SEV_PANIC;
 276	default:
 277		/* Unknown, go panic */
 278		return GHES_SEV_PANIC;
 279	}
 280}
 281
 282static void ghes_copy_tofrom_phys(void *buffer, u64 paddr, u32 len,
 283				  int from_phys,
 284				  enum fixed_addresses fixmap_idx)
 285{
 286	void __iomem *vaddr;
 287	u64 offset;
 288	u32 trunk;
 289
 290	while (len > 0) {
 291		offset = paddr - (paddr & PAGE_MASK);
 292		vaddr = ghes_map(PHYS_PFN(paddr), fixmap_idx);
 293		trunk = PAGE_SIZE - offset;
 294		trunk = min(trunk, len);
 295		if (from_phys)
 296			memcpy_fromio(buffer, vaddr + offset, trunk);
 297		else
 298			memcpy_toio(vaddr + offset, buffer, trunk);
 299		len -= trunk;
 300		paddr += trunk;
 301		buffer += trunk;
 302		ghes_unmap(vaddr, fixmap_idx);
 303	}
 304}
 305
 306/* Check the top-level record header has an appropriate size. */
 307static int __ghes_check_estatus(struct ghes *ghes,
 308				struct acpi_hest_generic_status *estatus)
 309{
 310	u32 len = cper_estatus_len(estatus);
 311
 312	if (len < sizeof(*estatus)) {
 313		pr_warn_ratelimited(FW_WARN GHES_PFX "Truncated error status block!\n");
 314		return -EIO;
 315	}
 316
 317	if (len > ghes->generic->error_block_length) {
 318		pr_warn_ratelimited(FW_WARN GHES_PFX "Invalid error status block length!\n");
 319		return -EIO;
 320	}
 321
 322	if (cper_estatus_check_header(estatus)) {
 323		pr_warn_ratelimited(FW_WARN GHES_PFX "Invalid CPER header!\n");
 324		return -EIO;
 325	}
 326
 327	return 0;
 328}
 329
 330/* Read the CPER block, returning its address, and header in estatus. */
 331static int __ghes_peek_estatus(struct ghes *ghes,
 332			       struct acpi_hest_generic_status *estatus,
 333			       u64 *buf_paddr, enum fixed_addresses fixmap_idx)
 334{
 335	struct acpi_hest_generic *g = ghes->generic;
 336	int rc;
 337
 338	rc = apei_read(buf_paddr, &g->error_status_address);
 339	if (rc) {
 340		*buf_paddr = 0;
 341		pr_warn_ratelimited(FW_WARN GHES_PFX
 342"Failed to read error status block address for hardware error source: %d.\n",
 343				   g->header.source_id);
 344		return -EIO;
 345	}
 346	if (!*buf_paddr)
 347		return -ENOENT;
 348
 349	ghes_copy_tofrom_phys(estatus, *buf_paddr, sizeof(*estatus), 1,
 350			      fixmap_idx);
 351	if (!estatus->block_status) {
 352		*buf_paddr = 0;
 353		return -ENOENT;
 354	}
 355
 356	return 0;
 357}
 358
 359static int __ghes_read_estatus(struct acpi_hest_generic_status *estatus,
 360			       u64 buf_paddr, enum fixed_addresses fixmap_idx,
 361			       size_t buf_len)
 362{
 363	ghes_copy_tofrom_phys(estatus, buf_paddr, buf_len, 1, fixmap_idx);
 364	if (cper_estatus_check(estatus)) {
 365		pr_warn_ratelimited(FW_WARN GHES_PFX
 366				    "Failed to read error status block!\n");
 367		return -EIO;
 368	}
 369
 370	return 0;
 371}
 372
 373static int ghes_read_estatus(struct ghes *ghes,
 374			     struct acpi_hest_generic_status *estatus,
 375			     u64 *buf_paddr, enum fixed_addresses fixmap_idx)
 376{
 377	int rc;
 378
 379	rc = __ghes_peek_estatus(ghes, estatus, buf_paddr, fixmap_idx);
 380	if (rc)
 381		return rc;
 382
 383	rc = __ghes_check_estatus(ghes, estatus);
 384	if (rc)
 385		return rc;
 386
 387	return __ghes_read_estatus(estatus, *buf_paddr, fixmap_idx,
 388				   cper_estatus_len(estatus));
 389}
 390
 391static void ghes_clear_estatus(struct ghes *ghes,
 392			       struct acpi_hest_generic_status *estatus,
 393			       u64 buf_paddr, enum fixed_addresses fixmap_idx)
 394{
 395	estatus->block_status = 0;
 396
 397	if (!buf_paddr)
 398		return;
 399
 400	ghes_copy_tofrom_phys(estatus, buf_paddr,
 401			      sizeof(estatus->block_status), 0,
 402			      fixmap_idx);
 403
 404	/*
 405	 * GHESv2 type HEST entries introduce support for error acknowledgment,
 406	 * so only acknowledge the error if this support is present.
 407	 */
 408	if (is_hest_type_generic_v2(ghes))
 409		ghes_ack_error(ghes->generic_v2);
 410}
 411
 412/*
 413 * Called as task_work before returning to user-space.
 414 * Ensure any queued work has been done before we return to the context that
 415 * triggered the notification.
 416 */
 417static void ghes_kick_task_work(struct callback_head *head)
 418{
 419	struct acpi_hest_generic_status *estatus;
 420	struct ghes_estatus_node *estatus_node;
 421	u32 node_len;
 422
 423	estatus_node = container_of(head, struct ghes_estatus_node, task_work);
 424	if (IS_ENABLED(CONFIG_ACPI_APEI_MEMORY_FAILURE))
 425		memory_failure_queue_kick(estatus_node->task_work_cpu);
 426
 427	estatus = GHES_ESTATUS_FROM_NODE(estatus_node);
 428	node_len = GHES_ESTATUS_NODE_LEN(cper_estatus_len(estatus));
 429	gen_pool_free(ghes_estatus_pool, (unsigned long)estatus_node, node_len);
 430}
 431
 432static bool ghes_handle_memory_failure(struct acpi_hest_generic_data *gdata,
 433				       int sev)
 434{
 435	unsigned long pfn;
 436	int flags = -1;
 437	int sec_sev = ghes_severity(gdata->error_severity);
 438	struct cper_sec_mem_err *mem_err = acpi_hest_get_payload(gdata);
 439
 440	if (!IS_ENABLED(CONFIG_ACPI_APEI_MEMORY_FAILURE))
 441		return false;
 442
 443	if (!(mem_err->validation_bits & CPER_MEM_VALID_PA))
 444		return false;
 445
 446	pfn = mem_err->physical_addr >> PAGE_SHIFT;
 447	if (!pfn_valid(pfn)) {
 448		pr_warn_ratelimited(FW_WARN GHES_PFX
 449		"Invalid address in generic error data: %#llx\n",
 450		mem_err->physical_addr);
 451		return false;
 452	}
 453
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 454	/* iff following two events can be handled properly by now */
 455	if (sec_sev == GHES_SEV_CORRECTED &&
 456	    (gdata->flags & CPER_SEC_ERROR_THRESHOLD_EXCEEDED))
 457		flags = MF_SOFT_OFFLINE;
 458	if (sev == GHES_SEV_RECOVERABLE && sec_sev == GHES_SEV_RECOVERABLE)
 459		flags = 0;
 460
 461	if (flags != -1) {
 462		memory_failure_queue(pfn, flags);
 463		return true;
 464	}
 465
 466	return false;
 467}
 468
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 469/*
 470 * PCIe AER errors need to be sent to the AER driver for reporting and
 471 * recovery. The GHES severities map to the following AER severities and
 472 * require the following handling:
 473 *
 474 * GHES_SEV_CORRECTABLE -> AER_CORRECTABLE
 475 *     These need to be reported by the AER driver but no recovery is
 476 *     necessary.
 477 * GHES_SEV_RECOVERABLE -> AER_NONFATAL
 478 * GHES_SEV_RECOVERABLE && CPER_SEC_RESET -> AER_FATAL
 479 *     These both need to be reported and recovered from by the AER driver.
 480 * GHES_SEV_PANIC does not make it to this handling since the kernel must
 481 *     panic.
 482 */
 483static void ghes_handle_aer(struct acpi_hest_generic_data *gdata)
 484{
 485#ifdef CONFIG_ACPI_APEI_PCIEAER
 486	struct cper_sec_pcie *pcie_err = acpi_hest_get_payload(gdata);
 487
 488	if (pcie_err->validation_bits & CPER_PCIE_VALID_DEVICE_ID &&
 489	    pcie_err->validation_bits & CPER_PCIE_VALID_AER_INFO) {
 490		unsigned int devfn;
 491		int aer_severity;
 492
 493		devfn = PCI_DEVFN(pcie_err->device_id.device,
 494				  pcie_err->device_id.function);
 495		aer_severity = cper_severity_to_aer(gdata->error_severity);
 496
 497		/*
 498		 * If firmware reset the component to contain
 499		 * the error, we must reinitialize it before
 500		 * use, so treat it as a fatal AER error.
 501		 */
 502		if (gdata->flags & CPER_SEC_RESET)
 503			aer_severity = AER_FATAL;
 504
 505		aer_recover_queue(pcie_err->device_id.segment,
 506				  pcie_err->device_id.bus,
 507				  devfn, aer_severity,
 508				  (struct aer_capability_regs *)
 509				  pcie_err->aer_info);
 510	}
 511#endif
 512}
 513
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 514static bool ghes_do_proc(struct ghes *ghes,
 515			 const struct acpi_hest_generic_status *estatus)
 516{
 517	int sev, sec_sev;
 518	struct acpi_hest_generic_data *gdata;
 519	guid_t *sec_type;
 520	const guid_t *fru_id = &guid_null;
 521	char *fru_text = "";
 522	bool queued = false;
 523
 524	sev = ghes_severity(estatus->error_severity);
 525	apei_estatus_for_each_section(estatus, gdata) {
 526		sec_type = (guid_t *)gdata->section_type;
 527		sec_sev = ghes_severity(gdata->error_severity);
 528		if (gdata->validation_bits & CPER_SEC_VALID_FRU_ID)
 529			fru_id = (guid_t *)gdata->fru_id;
 530
 531		if (gdata->validation_bits & CPER_SEC_VALID_FRU_TEXT)
 532			fru_text = gdata->fru_text;
 533
 534		if (guid_equal(sec_type, &CPER_SEC_PLATFORM_MEM)) {
 535			struct cper_sec_mem_err *mem_err = acpi_hest_get_payload(gdata);
 536
 537			ghes_edac_report_mem_error(sev, mem_err);
 538
 539			arch_apei_report_mem_error(sev, mem_err);
 540			queued = ghes_handle_memory_failure(gdata, sev);
 541		}
 542		else if (guid_equal(sec_type, &CPER_SEC_PCIE)) {
 543			ghes_handle_aer(gdata);
 544		}
 545		else if (guid_equal(sec_type, &CPER_SEC_PROC_ARM)) {
 546			struct cper_sec_proc_arm *err = acpi_hest_get_payload(gdata);
 547
 548			log_arm_hw_error(err);
 549		} else {
 550			void *err = acpi_hest_get_payload(gdata);
 551
 
 552			log_non_standard_event(sec_type, fru_id, fru_text,
 553					       sec_sev, err,
 554					       gdata->error_data_length);
 555		}
 556	}
 557
 558	return queued;
 559}
 560
 561static void __ghes_print_estatus(const char *pfx,
 562				 const struct acpi_hest_generic *generic,
 563				 const struct acpi_hest_generic_status *estatus)
 564{
 565	static atomic_t seqno;
 566	unsigned int curr_seqno;
 567	char pfx_seq[64];
 568
 569	if (pfx == NULL) {
 570		if (ghes_severity(estatus->error_severity) <=
 571		    GHES_SEV_CORRECTED)
 572			pfx = KERN_WARNING;
 573		else
 574			pfx = KERN_ERR;
 575	}
 576	curr_seqno = atomic_inc_return(&seqno);
 577	snprintf(pfx_seq, sizeof(pfx_seq), "%s{%u}" HW_ERR, pfx, curr_seqno);
 578	printk("%s""Hardware error from APEI Generic Hardware Error Source: %d\n",
 579	       pfx_seq, generic->header.source_id);
 580	cper_estatus_print(pfx_seq, estatus);
 581}
 582
 583static int ghes_print_estatus(const char *pfx,
 584			      const struct acpi_hest_generic *generic,
 585			      const struct acpi_hest_generic_status *estatus)
 586{
 587	/* Not more than 2 messages every 5 seconds */
 588	static DEFINE_RATELIMIT_STATE(ratelimit_corrected, 5*HZ, 2);
 589	static DEFINE_RATELIMIT_STATE(ratelimit_uncorrected, 5*HZ, 2);
 590	struct ratelimit_state *ratelimit;
 591
 592	if (ghes_severity(estatus->error_severity) <= GHES_SEV_CORRECTED)
 593		ratelimit = &ratelimit_corrected;
 594	else
 595		ratelimit = &ratelimit_uncorrected;
 596	if (__ratelimit(ratelimit)) {
 597		__ghes_print_estatus(pfx, generic, estatus);
 598		return 1;
 599	}
 600	return 0;
 601}
 602
 603/*
 604 * GHES error status reporting throttle, to report more kinds of
 605 * errors, instead of just most frequently occurred errors.
 606 */
 607static int ghes_estatus_cached(struct acpi_hest_generic_status *estatus)
 608{
 609	u32 len;
 610	int i, cached = 0;
 611	unsigned long long now;
 612	struct ghes_estatus_cache *cache;
 613	struct acpi_hest_generic_status *cache_estatus;
 614
 615	len = cper_estatus_len(estatus);
 616	rcu_read_lock();
 617	for (i = 0; i < GHES_ESTATUS_CACHES_SIZE; i++) {
 618		cache = rcu_dereference(ghes_estatus_caches[i]);
 619		if (cache == NULL)
 620			continue;
 621		if (len != cache->estatus_len)
 622			continue;
 623		cache_estatus = GHES_ESTATUS_FROM_CACHE(cache);
 624		if (memcmp(estatus, cache_estatus, len))
 625			continue;
 626		atomic_inc(&cache->count);
 627		now = sched_clock();
 628		if (now - cache->time_in < GHES_ESTATUS_IN_CACHE_MAX_NSEC)
 629			cached = 1;
 630		break;
 631	}
 632	rcu_read_unlock();
 633	return cached;
 634}
 635
 636static struct ghes_estatus_cache *ghes_estatus_cache_alloc(
 637	struct acpi_hest_generic *generic,
 638	struct acpi_hest_generic_status *estatus)
 639{
 640	int alloced;
 641	u32 len, cache_len;
 642	struct ghes_estatus_cache *cache;
 643	struct acpi_hest_generic_status *cache_estatus;
 644
 645	alloced = atomic_add_return(1, &ghes_estatus_cache_alloced);
 646	if (alloced > GHES_ESTATUS_CACHE_ALLOCED_MAX) {
 647		atomic_dec(&ghes_estatus_cache_alloced);
 648		return NULL;
 649	}
 650	len = cper_estatus_len(estatus);
 651	cache_len = GHES_ESTATUS_CACHE_LEN(len);
 652	cache = (void *)gen_pool_alloc(ghes_estatus_pool, cache_len);
 653	if (!cache) {
 654		atomic_dec(&ghes_estatus_cache_alloced);
 655		return NULL;
 656	}
 657	cache_estatus = GHES_ESTATUS_FROM_CACHE(cache);
 658	memcpy(cache_estatus, estatus, len);
 659	cache->estatus_len = len;
 660	atomic_set(&cache->count, 0);
 661	cache->generic = generic;
 662	cache->time_in = sched_clock();
 663	return cache;
 664}
 665
 666static void ghes_estatus_cache_free(struct ghes_estatus_cache *cache)
 667{
 
 668	u32 len;
 669
 
 670	len = cper_estatus_len(GHES_ESTATUS_FROM_CACHE(cache));
 671	len = GHES_ESTATUS_CACHE_LEN(len);
 672	gen_pool_free(ghes_estatus_pool, (unsigned long)cache, len);
 673	atomic_dec(&ghes_estatus_cache_alloced);
 674}
 675
 676static void ghes_estatus_cache_rcu_free(struct rcu_head *head)
 677{
 678	struct ghes_estatus_cache *cache;
 679
 680	cache = container_of(head, struct ghes_estatus_cache, rcu);
 681	ghes_estatus_cache_free(cache);
 682}
 683
 684static void ghes_estatus_cache_add(
 685	struct acpi_hest_generic *generic,
 686	struct acpi_hest_generic_status *estatus)
 687{
 688	int i, slot = -1, count;
 689	unsigned long long now, duration, period, max_period = 0;
 690	struct ghes_estatus_cache *cache, *slot_cache = NULL, *new_cache;
 
 
 691
 692	new_cache = ghes_estatus_cache_alloc(generic, estatus);
 693	if (new_cache == NULL)
 694		return;
 
 695	rcu_read_lock();
 696	now = sched_clock();
 697	for (i = 0; i < GHES_ESTATUS_CACHES_SIZE; i++) {
 698		cache = rcu_dereference(ghes_estatus_caches[i]);
 699		if (cache == NULL) {
 700			slot = i;
 701			slot_cache = NULL;
 702			break;
 703		}
 704		duration = now - cache->time_in;
 705		if (duration >= GHES_ESTATUS_IN_CACHE_MAX_NSEC) {
 706			slot = i;
 707			slot_cache = cache;
 708			break;
 709		}
 710		count = atomic_read(&cache->count);
 711		period = duration;
 712		do_div(period, (count + 1));
 713		if (period > max_period) {
 714			max_period = period;
 715			slot = i;
 716			slot_cache = cache;
 717		}
 718	}
 719	/* new_cache must be put into array after its contents are written */
 720	smp_wmb();
 721	if (slot != -1 && cmpxchg(ghes_estatus_caches + slot,
 722				  slot_cache, new_cache) == slot_cache) {
 723		if (slot_cache)
 724			call_rcu(&slot_cache->rcu, ghes_estatus_cache_rcu_free);
 725	} else
 726		ghes_estatus_cache_free(new_cache);
 727	rcu_read_unlock();
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 728}
 729
 730static void __ghes_panic(struct ghes *ghes,
 731			 struct acpi_hest_generic_status *estatus,
 732			 u64 buf_paddr, enum fixed_addresses fixmap_idx)
 733{
 734	__ghes_print_estatus(KERN_EMERG, ghes->generic, estatus);
 735
 736	ghes_clear_estatus(ghes, estatus, buf_paddr, fixmap_idx);
 737
 738	/* reboot to log the error! */
 739	if (!panic_timeout)
 740		panic_timeout = ghes_panic_timeout;
 741	panic("Fatal hardware error!");
 742}
 743
 744static int ghes_proc(struct ghes *ghes)
 745{
 746	struct acpi_hest_generic_status *estatus = ghes->estatus;
 747	u64 buf_paddr;
 748	int rc;
 749
 750	rc = ghes_read_estatus(ghes, estatus, &buf_paddr, FIX_APEI_GHES_IRQ);
 751	if (rc)
 752		goto out;
 753
 754	if (ghes_severity(estatus->error_severity) >= GHES_SEV_PANIC)
 755		__ghes_panic(ghes, estatus, buf_paddr, FIX_APEI_GHES_IRQ);
 756
 757	if (!ghes_estatus_cached(estatus)) {
 758		if (ghes_print_estatus(NULL, ghes->generic, estatus))
 759			ghes_estatus_cache_add(ghes->generic, estatus);
 760	}
 761	ghes_do_proc(ghes, estatus);
 762
 763out:
 764	ghes_clear_estatus(ghes, estatus, buf_paddr, FIX_APEI_GHES_IRQ);
 765
 766	return rc;
 767}
 768
 769static void ghes_add_timer(struct ghes *ghes)
 770{
 771	struct acpi_hest_generic *g = ghes->generic;
 772	unsigned long expire;
 773
 774	if (!g->notify.poll_interval) {
 775		pr_warn(FW_WARN GHES_PFX "Poll interval is 0 for generic hardware error source: %d, disabled.\n",
 776			g->header.source_id);
 777		return;
 778	}
 779	expire = jiffies + msecs_to_jiffies(g->notify.poll_interval);
 780	ghes->timer.expires = round_jiffies_relative(expire);
 781	add_timer(&ghes->timer);
 782}
 783
 784static void ghes_poll_func(struct timer_list *t)
 785{
 786	struct ghes *ghes = from_timer(ghes, t, timer);
 787	unsigned long flags;
 788
 789	spin_lock_irqsave(&ghes_notify_lock_irq, flags);
 790	ghes_proc(ghes);
 791	spin_unlock_irqrestore(&ghes_notify_lock_irq, flags);
 792	if (!(ghes->flags & GHES_EXITING))
 793		ghes_add_timer(ghes);
 794}
 795
 796static irqreturn_t ghes_irq_func(int irq, void *data)
 797{
 798	struct ghes *ghes = data;
 799	unsigned long flags;
 800	int rc;
 801
 802	spin_lock_irqsave(&ghes_notify_lock_irq, flags);
 803	rc = ghes_proc(ghes);
 804	spin_unlock_irqrestore(&ghes_notify_lock_irq, flags);
 805	if (rc)
 806		return IRQ_NONE;
 807
 808	return IRQ_HANDLED;
 809}
 810
 811static int ghes_notify_hed(struct notifier_block *this, unsigned long event,
 812			   void *data)
 813{
 814	struct ghes *ghes;
 815	unsigned long flags;
 816	int ret = NOTIFY_DONE;
 817
 818	spin_lock_irqsave(&ghes_notify_lock_irq, flags);
 819	rcu_read_lock();
 820	list_for_each_entry_rcu(ghes, &ghes_hed, list) {
 821		if (!ghes_proc(ghes))
 822			ret = NOTIFY_OK;
 823	}
 824	rcu_read_unlock();
 825	spin_unlock_irqrestore(&ghes_notify_lock_irq, flags);
 826
 827	return ret;
 828}
 829
 830static struct notifier_block ghes_notifier_hed = {
 831	.notifier_call = ghes_notify_hed,
 832};
 833
 834/*
 835 * Handlers for CPER records may not be NMI safe. For example,
 836 * memory_failure_queue() takes spinlocks and calls schedule_work_on().
 837 * In any NMI-like handler, memory from ghes_estatus_pool is used to save
 838 * estatus, and added to the ghes_estatus_llist. irq_work_queue() causes
 839 * ghes_proc_in_irq() to run in IRQ context where each estatus in
 840 * ghes_estatus_llist is processed.
 841 *
 842 * Memory from the ghes_estatus_pool is also used with the ghes_estatus_cache
 843 * to suppress frequent messages.
 844 */
 845static struct llist_head ghes_estatus_llist;
 846static struct irq_work ghes_proc_irq_work;
 847
 848static void ghes_proc_in_irq(struct irq_work *irq_work)
 849{
 850	struct llist_node *llnode, *next;
 851	struct ghes_estatus_node *estatus_node;
 852	struct acpi_hest_generic *generic;
 853	struct acpi_hest_generic_status *estatus;
 854	bool task_work_pending;
 855	u32 len, node_len;
 856	int ret;
 857
 858	llnode = llist_del_all(&ghes_estatus_llist);
 859	/*
 860	 * Because the time order of estatus in list is reversed,
 861	 * revert it back to proper order.
 862	 */
 863	llnode = llist_reverse_order(llnode);
 864	while (llnode) {
 865		next = llnode->next;
 866		estatus_node = llist_entry(llnode, struct ghes_estatus_node,
 867					   llnode);
 868		estatus = GHES_ESTATUS_FROM_NODE(estatus_node);
 869		len = cper_estatus_len(estatus);
 870		node_len = GHES_ESTATUS_NODE_LEN(len);
 871		task_work_pending = ghes_do_proc(estatus_node->ghes, estatus);
 872		if (!ghes_estatus_cached(estatus)) {
 873			generic = estatus_node->generic;
 874			if (ghes_print_estatus(NULL, generic, estatus))
 875				ghes_estatus_cache_add(generic, estatus);
 876		}
 877
 878		if (task_work_pending && current->mm != &init_mm) {
 879			estatus_node->task_work.func = ghes_kick_task_work;
 880			estatus_node->task_work_cpu = smp_processor_id();
 881			ret = task_work_add(current, &estatus_node->task_work,
 882					    true);
 883			if (ret)
 884				estatus_node->task_work.func = NULL;
 885		}
 886
 887		if (!estatus_node->task_work.func)
 888			gen_pool_free(ghes_estatus_pool,
 889				      (unsigned long)estatus_node, node_len);
 890
 891		llnode = next;
 892	}
 893}
 894
 895static void ghes_print_queued_estatus(void)
 896{
 897	struct llist_node *llnode;
 898	struct ghes_estatus_node *estatus_node;
 899	struct acpi_hest_generic *generic;
 900	struct acpi_hest_generic_status *estatus;
 901
 902	llnode = llist_del_all(&ghes_estatus_llist);
 903	/*
 904	 * Because the time order of estatus in list is reversed,
 905	 * revert it back to proper order.
 906	 */
 907	llnode = llist_reverse_order(llnode);
 908	while (llnode) {
 909		estatus_node = llist_entry(llnode, struct ghes_estatus_node,
 910					   llnode);
 911		estatus = GHES_ESTATUS_FROM_NODE(estatus_node);
 912		generic = estatus_node->generic;
 913		ghes_print_estatus(NULL, generic, estatus);
 914		llnode = llnode->next;
 915	}
 916}
 917
 918static int ghes_in_nmi_queue_one_entry(struct ghes *ghes,
 919				       enum fixed_addresses fixmap_idx)
 920{
 921	struct acpi_hest_generic_status *estatus, tmp_header;
 922	struct ghes_estatus_node *estatus_node;
 923	u32 len, node_len;
 924	u64 buf_paddr;
 925	int sev, rc;
 926
 927	if (!IS_ENABLED(CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG))
 928		return -EOPNOTSUPP;
 929
 930	rc = __ghes_peek_estatus(ghes, &tmp_header, &buf_paddr, fixmap_idx);
 931	if (rc) {
 932		ghes_clear_estatus(ghes, &tmp_header, buf_paddr, fixmap_idx);
 933		return rc;
 934	}
 935
 936	rc = __ghes_check_estatus(ghes, &tmp_header);
 937	if (rc) {
 938		ghes_clear_estatus(ghes, &tmp_header, buf_paddr, fixmap_idx);
 939		return rc;
 940	}
 941
 942	len = cper_estatus_len(&tmp_header);
 943	node_len = GHES_ESTATUS_NODE_LEN(len);
 944	estatus_node = (void *)gen_pool_alloc(ghes_estatus_pool, node_len);
 945	if (!estatus_node)
 946		return -ENOMEM;
 947
 948	estatus_node->ghes = ghes;
 949	estatus_node->generic = ghes->generic;
 950	estatus_node->task_work.func = NULL;
 951	estatus = GHES_ESTATUS_FROM_NODE(estatus_node);
 952
 953	if (__ghes_read_estatus(estatus, buf_paddr, fixmap_idx, len)) {
 954		ghes_clear_estatus(ghes, estatus, buf_paddr, fixmap_idx);
 955		rc = -ENOENT;
 956		goto no_work;
 957	}
 958
 959	sev = ghes_severity(estatus->error_severity);
 960	if (sev >= GHES_SEV_PANIC) {
 961		ghes_print_queued_estatus();
 962		__ghes_panic(ghes, estatus, buf_paddr, fixmap_idx);
 963	}
 964
 965	ghes_clear_estatus(ghes, &tmp_header, buf_paddr, fixmap_idx);
 966
 967	/* This error has been reported before, don't process it again. */
 968	if (ghes_estatus_cached(estatus))
 969		goto no_work;
 970
 971	llist_add(&estatus_node->llnode, &ghes_estatus_llist);
 972
 973	return rc;
 974
 975no_work:
 976	gen_pool_free(ghes_estatus_pool, (unsigned long)estatus_node,
 977		      node_len);
 978
 979	return rc;
 980}
 981
 982static int ghes_in_nmi_spool_from_list(struct list_head *rcu_list,
 983				       enum fixed_addresses fixmap_idx)
 984{
 985	int ret = -ENOENT;
 986	struct ghes *ghes;
 987
 988	rcu_read_lock();
 989	list_for_each_entry_rcu(ghes, rcu_list, list) {
 990		if (!ghes_in_nmi_queue_one_entry(ghes, fixmap_idx))
 991			ret = 0;
 992	}
 993	rcu_read_unlock();
 994
 995	if (IS_ENABLED(CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG) && !ret)
 996		irq_work_queue(&ghes_proc_irq_work);
 997
 998	return ret;
 999}
1000
1001#ifdef CONFIG_ACPI_APEI_SEA
1002static LIST_HEAD(ghes_sea);
1003
1004/*
1005 * Return 0 only if one of the SEA error sources successfully reported an error
1006 * record sent from the firmware.
1007 */
1008int ghes_notify_sea(void)
1009{
1010	static DEFINE_RAW_SPINLOCK(ghes_notify_lock_sea);
1011	int rv;
1012
1013	raw_spin_lock(&ghes_notify_lock_sea);
1014	rv = ghes_in_nmi_spool_from_list(&ghes_sea, FIX_APEI_GHES_SEA);
1015	raw_spin_unlock(&ghes_notify_lock_sea);
1016
1017	return rv;
1018}
1019
1020static void ghes_sea_add(struct ghes *ghes)
1021{
1022	mutex_lock(&ghes_list_mutex);
1023	list_add_rcu(&ghes->list, &ghes_sea);
1024	mutex_unlock(&ghes_list_mutex);
1025}
1026
1027static void ghes_sea_remove(struct ghes *ghes)
1028{
1029	mutex_lock(&ghes_list_mutex);
1030	list_del_rcu(&ghes->list);
1031	mutex_unlock(&ghes_list_mutex);
1032	synchronize_rcu();
1033}
1034#else /* CONFIG_ACPI_APEI_SEA */
1035static inline void ghes_sea_add(struct ghes *ghes) { }
1036static inline void ghes_sea_remove(struct ghes *ghes) { }
1037#endif /* CONFIG_ACPI_APEI_SEA */
1038
1039#ifdef CONFIG_HAVE_ACPI_APEI_NMI
1040/*
1041 * NMI may be triggered on any CPU, so ghes_in_nmi is used for
1042 * having only one concurrent reader.
1043 */
1044static atomic_t ghes_in_nmi = ATOMIC_INIT(0);
1045
1046static LIST_HEAD(ghes_nmi);
1047
1048static int ghes_notify_nmi(unsigned int cmd, struct pt_regs *regs)
1049{
1050	static DEFINE_RAW_SPINLOCK(ghes_notify_lock_nmi);
1051	int ret = NMI_DONE;
1052
1053	if (!atomic_add_unless(&ghes_in_nmi, 1, 1))
1054		return ret;
1055
1056	raw_spin_lock(&ghes_notify_lock_nmi);
1057	if (!ghes_in_nmi_spool_from_list(&ghes_nmi, FIX_APEI_GHES_NMI))
1058		ret = NMI_HANDLED;
1059	raw_spin_unlock(&ghes_notify_lock_nmi);
1060
1061	atomic_dec(&ghes_in_nmi);
1062	return ret;
1063}
1064
1065static void ghes_nmi_add(struct ghes *ghes)
1066{
1067	mutex_lock(&ghes_list_mutex);
1068	if (list_empty(&ghes_nmi))
1069		register_nmi_handler(NMI_LOCAL, ghes_notify_nmi, 0, "ghes");
1070	list_add_rcu(&ghes->list, &ghes_nmi);
1071	mutex_unlock(&ghes_list_mutex);
1072}
1073
1074static void ghes_nmi_remove(struct ghes *ghes)
1075{
1076	mutex_lock(&ghes_list_mutex);
1077	list_del_rcu(&ghes->list);
1078	if (list_empty(&ghes_nmi))
1079		unregister_nmi_handler(NMI_LOCAL, "ghes");
1080	mutex_unlock(&ghes_list_mutex);
1081	/*
1082	 * To synchronize with NMI handler, ghes can only be
1083	 * freed after NMI handler finishes.
1084	 */
1085	synchronize_rcu();
1086}
1087#else /* CONFIG_HAVE_ACPI_APEI_NMI */
1088static inline void ghes_nmi_add(struct ghes *ghes) { }
1089static inline void ghes_nmi_remove(struct ghes *ghes) { }
1090#endif /* CONFIG_HAVE_ACPI_APEI_NMI */
1091
1092static void ghes_nmi_init_cxt(void)
1093{
1094	init_irq_work(&ghes_proc_irq_work, ghes_proc_in_irq);
1095}
1096
1097static int __ghes_sdei_callback(struct ghes *ghes,
1098				enum fixed_addresses fixmap_idx)
1099{
1100	if (!ghes_in_nmi_queue_one_entry(ghes, fixmap_idx)) {
1101		irq_work_queue(&ghes_proc_irq_work);
1102
1103		return 0;
1104	}
1105
1106	return -ENOENT;
1107}
1108
1109static int ghes_sdei_normal_callback(u32 event_num, struct pt_regs *regs,
1110				      void *arg)
1111{
1112	static DEFINE_RAW_SPINLOCK(ghes_notify_lock_sdei_normal);
1113	struct ghes *ghes = arg;
1114	int err;
1115
1116	raw_spin_lock(&ghes_notify_lock_sdei_normal);
1117	err = __ghes_sdei_callback(ghes, FIX_APEI_GHES_SDEI_NORMAL);
1118	raw_spin_unlock(&ghes_notify_lock_sdei_normal);
1119
1120	return err;
1121}
1122
1123static int ghes_sdei_critical_callback(u32 event_num, struct pt_regs *regs,
1124				       void *arg)
1125{
1126	static DEFINE_RAW_SPINLOCK(ghes_notify_lock_sdei_critical);
1127	struct ghes *ghes = arg;
1128	int err;
1129
1130	raw_spin_lock(&ghes_notify_lock_sdei_critical);
1131	err = __ghes_sdei_callback(ghes, FIX_APEI_GHES_SDEI_CRITICAL);
1132	raw_spin_unlock(&ghes_notify_lock_sdei_critical);
1133
1134	return err;
1135}
1136
1137static int apei_sdei_register_ghes(struct ghes *ghes)
1138{
1139	if (!IS_ENABLED(CONFIG_ARM_SDE_INTERFACE))
1140		return -EOPNOTSUPP;
1141
1142	return sdei_register_ghes(ghes, ghes_sdei_normal_callback,
1143				 ghes_sdei_critical_callback);
1144}
1145
1146static int apei_sdei_unregister_ghes(struct ghes *ghes)
1147{
1148	if (!IS_ENABLED(CONFIG_ARM_SDE_INTERFACE))
1149		return -EOPNOTSUPP;
1150
1151	return sdei_unregister_ghes(ghes);
1152}
1153
1154static int ghes_probe(struct platform_device *ghes_dev)
1155{
1156	struct acpi_hest_generic *generic;
1157	struct ghes *ghes = NULL;
1158	unsigned long flags;
1159
1160	int rc = -EINVAL;
1161
1162	generic = *(struct acpi_hest_generic **)ghes_dev->dev.platform_data;
1163	if (!generic->enabled)
1164		return -ENODEV;
1165
1166	switch (generic->notify.type) {
1167	case ACPI_HEST_NOTIFY_POLLED:
1168	case ACPI_HEST_NOTIFY_EXTERNAL:
1169	case ACPI_HEST_NOTIFY_SCI:
1170	case ACPI_HEST_NOTIFY_GSIV:
1171	case ACPI_HEST_NOTIFY_GPIO:
1172		break;
1173
1174	case ACPI_HEST_NOTIFY_SEA:
1175		if (!IS_ENABLED(CONFIG_ACPI_APEI_SEA)) {
1176			pr_warn(GHES_PFX "Generic hardware error source: %d notified via SEA is not supported\n",
1177				generic->header.source_id);
1178			rc = -ENOTSUPP;
1179			goto err;
1180		}
1181		break;
1182	case ACPI_HEST_NOTIFY_NMI:
1183		if (!IS_ENABLED(CONFIG_HAVE_ACPI_APEI_NMI)) {
1184			pr_warn(GHES_PFX "Generic hardware error source: %d notified via NMI interrupt is not supported!\n",
1185				generic->header.source_id);
1186			goto err;
1187		}
1188		break;
1189	case ACPI_HEST_NOTIFY_SOFTWARE_DELEGATED:
1190		if (!IS_ENABLED(CONFIG_ARM_SDE_INTERFACE)) {
1191			pr_warn(GHES_PFX "Generic hardware error source: %d notified via SDE Interface is not supported!\n",
1192				generic->header.source_id);
1193			goto err;
1194		}
1195		break;
1196	case ACPI_HEST_NOTIFY_LOCAL:
1197		pr_warn(GHES_PFX "Generic hardware error source: %d notified via local interrupt is not supported!\n",
1198			generic->header.source_id);
1199		goto err;
1200	default:
1201		pr_warn(FW_WARN GHES_PFX "Unknown notification type: %u for generic hardware error source: %d\n",
1202			generic->notify.type, generic->header.source_id);
1203		goto err;
1204	}
1205
1206	rc = -EIO;
1207	if (generic->error_block_length <
1208	    sizeof(struct acpi_hest_generic_status)) {
1209		pr_warn(FW_BUG GHES_PFX "Invalid error block length: %u for generic hardware error source: %d\n",
1210			generic->error_block_length, generic->header.source_id);
1211		goto err;
1212	}
1213	ghes = ghes_new(generic);
1214	if (IS_ERR(ghes)) {
1215		rc = PTR_ERR(ghes);
1216		ghes = NULL;
1217		goto err;
1218	}
1219
1220	switch (generic->notify.type) {
1221	case ACPI_HEST_NOTIFY_POLLED:
1222		timer_setup(&ghes->timer, ghes_poll_func, 0);
1223		ghes_add_timer(ghes);
1224		break;
1225	case ACPI_HEST_NOTIFY_EXTERNAL:
1226		/* External interrupt vector is GSI */
1227		rc = acpi_gsi_to_irq(generic->notify.vector, &ghes->irq);
1228		if (rc) {
1229			pr_err(GHES_PFX "Failed to map GSI to IRQ for generic hardware error source: %d\n",
1230			       generic->header.source_id);
1231			goto err;
1232		}
1233		rc = request_irq(ghes->irq, ghes_irq_func, IRQF_SHARED,
1234				 "GHES IRQ", ghes);
1235		if (rc) {
1236			pr_err(GHES_PFX "Failed to register IRQ for generic hardware error source: %d\n",
1237			       generic->header.source_id);
1238			goto err;
1239		}
1240		break;
1241
1242	case ACPI_HEST_NOTIFY_SCI:
1243	case ACPI_HEST_NOTIFY_GSIV:
1244	case ACPI_HEST_NOTIFY_GPIO:
1245		mutex_lock(&ghes_list_mutex);
1246		if (list_empty(&ghes_hed))
1247			register_acpi_hed_notifier(&ghes_notifier_hed);
1248		list_add_rcu(&ghes->list, &ghes_hed);
1249		mutex_unlock(&ghes_list_mutex);
1250		break;
1251
1252	case ACPI_HEST_NOTIFY_SEA:
1253		ghes_sea_add(ghes);
1254		break;
1255	case ACPI_HEST_NOTIFY_NMI:
1256		ghes_nmi_add(ghes);
1257		break;
1258	case ACPI_HEST_NOTIFY_SOFTWARE_DELEGATED:
1259		rc = apei_sdei_register_ghes(ghes);
1260		if (rc)
1261			goto err;
1262		break;
1263	default:
1264		BUG();
1265	}
1266
1267	platform_set_drvdata(ghes_dev, ghes);
1268
1269	ghes_edac_register(ghes, &ghes_dev->dev);
 
 
 
 
1270
1271	/* Handle any pending errors right away */
1272	spin_lock_irqsave(&ghes_notify_lock_irq, flags);
1273	ghes_proc(ghes);
1274	spin_unlock_irqrestore(&ghes_notify_lock_irq, flags);
1275
1276	return 0;
1277
1278err:
1279	if (ghes) {
1280		ghes_fini(ghes);
1281		kfree(ghes);
1282	}
1283	return rc;
1284}
1285
1286static int ghes_remove(struct platform_device *ghes_dev)
1287{
1288	int rc;
1289	struct ghes *ghes;
1290	struct acpi_hest_generic *generic;
1291
1292	ghes = platform_get_drvdata(ghes_dev);
1293	generic = ghes->generic;
1294
1295	ghes->flags |= GHES_EXITING;
1296	switch (generic->notify.type) {
1297	case ACPI_HEST_NOTIFY_POLLED:
1298		del_timer_sync(&ghes->timer);
1299		break;
1300	case ACPI_HEST_NOTIFY_EXTERNAL:
1301		free_irq(ghes->irq, ghes);
1302		break;
1303
1304	case ACPI_HEST_NOTIFY_SCI:
1305	case ACPI_HEST_NOTIFY_GSIV:
1306	case ACPI_HEST_NOTIFY_GPIO:
1307		mutex_lock(&ghes_list_mutex);
1308		list_del_rcu(&ghes->list);
1309		if (list_empty(&ghes_hed))
1310			unregister_acpi_hed_notifier(&ghes_notifier_hed);
1311		mutex_unlock(&ghes_list_mutex);
1312		synchronize_rcu();
1313		break;
1314
1315	case ACPI_HEST_NOTIFY_SEA:
1316		ghes_sea_remove(ghes);
1317		break;
1318	case ACPI_HEST_NOTIFY_NMI:
1319		ghes_nmi_remove(ghes);
1320		break;
1321	case ACPI_HEST_NOTIFY_SOFTWARE_DELEGATED:
1322		rc = apei_sdei_unregister_ghes(ghes);
1323		if (rc)
1324			return rc;
1325		break;
1326	default:
1327		BUG();
1328		break;
1329	}
1330
1331	ghes_fini(ghes);
1332
1333	ghes_edac_unregister(ghes);
 
 
1334
1335	kfree(ghes);
1336
1337	platform_set_drvdata(ghes_dev, NULL);
1338
1339	return 0;
1340}
1341
1342static struct platform_driver ghes_platform_driver = {
1343	.driver		= {
1344		.name	= "GHES",
1345	},
1346	.probe		= ghes_probe,
1347	.remove		= ghes_remove,
1348};
1349
1350static int __init ghes_init(void)
1351{
1352	int rc;
1353
 
 
1354	if (acpi_disabled)
1355		return -ENODEV;
1356
1357	switch (hest_disable) {
1358	case HEST_NOT_FOUND:
1359		return -ENODEV;
1360	case HEST_DISABLED:
1361		pr_info(GHES_PFX "HEST is not enabled!\n");
1362		return -EINVAL;
1363	default:
1364		break;
1365	}
1366
1367	if (ghes_disable) {
1368		pr_info(GHES_PFX "GHES is not enabled!\n");
1369		return -EINVAL;
1370	}
1371
1372	ghes_nmi_init_cxt();
1373
1374	rc = platform_driver_register(&ghes_platform_driver);
1375	if (rc)
1376		goto err;
1377
1378	rc = apei_osc_setup();
1379	if (rc == 0 && osc_sb_apei_support_acked)
1380		pr_info(GHES_PFX "APEI firmware first mode is enabled by APEI bit and WHEA _OSC.\n");
1381	else if (rc == 0 && !osc_sb_apei_support_acked)
1382		pr_info(GHES_PFX "APEI firmware first mode is enabled by WHEA _OSC.\n");
1383	else if (rc && osc_sb_apei_support_acked)
1384		pr_info(GHES_PFX "APEI firmware first mode is enabled by APEI bit.\n");
1385	else
1386		pr_info(GHES_PFX "Failed to enable APEI firmware first mode.\n");
 
1387
1388	return 0;
1389err:
1390	return rc;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1391}
1392device_initcall(ghes_init);
v6.2
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * APEI Generic Hardware Error Source support
   4 *
   5 * Generic Hardware Error Source provides a way to report platform
   6 * hardware errors (such as that from chipset). It works in so called
   7 * "Firmware First" mode, that is, hardware errors are reported to
   8 * firmware firstly, then reported to Linux by firmware. This way,
   9 * some non-standard hardware error registers or non-standard hardware
  10 * link can be checked by firmware to produce more hardware error
  11 * information for Linux.
  12 *
  13 * For more information about Generic Hardware Error Source, please
  14 * refer to ACPI Specification version 4.0, section 17.3.2.6
  15 *
  16 * Copyright 2010,2011 Intel Corp.
  17 *   Author: Huang Ying <ying.huang@intel.com>
  18 */
  19
  20#include <linux/arm_sdei.h>
  21#include <linux/kernel.h>
  22#include <linux/moduleparam.h>
  23#include <linux/init.h>
  24#include <linux/acpi.h>
  25#include <linux/io.h>
  26#include <linux/interrupt.h>
  27#include <linux/timer.h>
  28#include <linux/cper.h>
  29#include <linux/platform_device.h>
  30#include <linux/mutex.h>
  31#include <linux/ratelimit.h>
  32#include <linux/vmalloc.h>
  33#include <linux/irq_work.h>
  34#include <linux/llist.h>
  35#include <linux/genalloc.h>
  36#include <linux/pci.h>
  37#include <linux/pfn.h>
  38#include <linux/aer.h>
  39#include <linux/nmi.h>
  40#include <linux/sched/clock.h>
  41#include <linux/uuid.h>
  42#include <linux/ras.h>
  43#include <linux/task_work.h>
  44
  45#include <acpi/actbl1.h>
  46#include <acpi/ghes.h>
  47#include <acpi/apei.h>
  48#include <asm/fixmap.h>
  49#include <asm/tlbflush.h>
  50#include <ras/ras_event.h>
  51
  52#include "apei-internal.h"
  53
  54#define GHES_PFX	"GHES: "
  55
  56#define GHES_ESTATUS_MAX_SIZE		65536
  57#define GHES_ESOURCE_PREALLOC_MAX_SIZE	65536
  58
  59#define GHES_ESTATUS_POOL_MIN_ALLOC_ORDER 3
  60
  61/* This is just an estimation for memory pool allocation */
  62#define GHES_ESTATUS_CACHE_AVG_SIZE	512
  63
  64#define GHES_ESTATUS_CACHES_SIZE	4
  65
  66#define GHES_ESTATUS_IN_CACHE_MAX_NSEC	10000000000ULL
  67/* Prevent too many caches are allocated because of RCU */
  68#define GHES_ESTATUS_CACHE_ALLOCED_MAX	(GHES_ESTATUS_CACHES_SIZE * 3 / 2)
  69
  70#define GHES_ESTATUS_CACHE_LEN(estatus_len)			\
  71	(sizeof(struct ghes_estatus_cache) + (estatus_len))
  72#define GHES_ESTATUS_FROM_CACHE(estatus_cache)			\
  73	((struct acpi_hest_generic_status *)				\
  74	 ((struct ghes_estatus_cache *)(estatus_cache) + 1))
  75
  76#define GHES_ESTATUS_NODE_LEN(estatus_len)			\
  77	(sizeof(struct ghes_estatus_node) + (estatus_len))
  78#define GHES_ESTATUS_FROM_NODE(estatus_node)			\
  79	((struct acpi_hest_generic_status *)				\
  80	 ((struct ghes_estatus_node *)(estatus_node) + 1))
  81
  82#define GHES_VENDOR_ENTRY_LEN(gdata_len)                               \
  83	(sizeof(struct ghes_vendor_record_entry) + (gdata_len))
  84#define GHES_GDATA_FROM_VENDOR_ENTRY(vendor_entry)                     \
  85	((struct acpi_hest_generic_data *)                              \
  86	((struct ghes_vendor_record_entry *)(vendor_entry) + 1))
  87
  88/*
  89 *  NMI-like notifications vary by architecture, before the compiler can prune
  90 *  unused static functions it needs a value for these enums.
  91 */
  92#ifndef CONFIG_ARM_SDE_INTERFACE
  93#define FIX_APEI_GHES_SDEI_NORMAL	__end_of_fixed_addresses
  94#define FIX_APEI_GHES_SDEI_CRITICAL	__end_of_fixed_addresses
  95#endif
  96
  97static ATOMIC_NOTIFIER_HEAD(ghes_report_chain);
  98
  99static inline bool is_hest_type_generic_v2(struct ghes *ghes)
 100{
 101	return ghes->generic->header.type == ACPI_HEST_TYPE_GENERIC_ERROR_V2;
 102}
 103
 104/*
 105 * This driver isn't really modular, however for the time being,
 106 * continuing to use module_param is the easiest way to remain
 107 * compatible with existing boot arg use cases.
 108 */
 109bool ghes_disable;
 110module_param_named(disable, ghes_disable, bool, 0);
 111
 112/*
 113 * "ghes.edac_force_enable" forcibly enables ghes_edac and skips the platform
 114 * check.
 115 */
 116static bool ghes_edac_force_enable;
 117module_param_named(edac_force_enable, ghes_edac_force_enable, bool, 0);
 118
 119/*
 120 * All error sources notified with HED (Hardware Error Device) share a
 121 * single notifier callback, so they need to be linked and checked one
 122 * by one. This holds true for NMI too.
 123 *
 124 * RCU is used for these lists, so ghes_list_mutex is only used for
 125 * list changing, not for traversing.
 126 */
 127static LIST_HEAD(ghes_hed);
 128static DEFINE_MUTEX(ghes_list_mutex);
 129
 130/*
 131 * A list of GHES devices which are given to the corresponding EDAC driver
 132 * ghes_edac for further use.
 133 */
 134static LIST_HEAD(ghes_devs);
 135static DEFINE_MUTEX(ghes_devs_mutex);
 136
 137/*
 138 * Because the memory area used to transfer hardware error information
 139 * from BIOS to Linux can be determined only in NMI, IRQ or timer
 140 * handler, but general ioremap can not be used in atomic context, so
 141 * the fixmap is used instead.
 142 *
 143 * This spinlock is used to prevent the fixmap entry from being used
 144 * simultaneously.
 145 */
 146static DEFINE_SPINLOCK(ghes_notify_lock_irq);
 147
 148struct ghes_vendor_record_entry {
 149	struct work_struct work;
 150	int error_severity;
 151	char vendor_record[];
 152};
 153
 154static struct gen_pool *ghes_estatus_pool;
 155static unsigned long ghes_estatus_pool_size_request;
 156
 157static struct ghes_estatus_cache __rcu *ghes_estatus_caches[GHES_ESTATUS_CACHES_SIZE];
 158static atomic_t ghes_estatus_cache_alloced;
 159
 160static int ghes_panic_timeout __read_mostly = 30;
 161
 162static void __iomem *ghes_map(u64 pfn, enum fixed_addresses fixmap_idx)
 163{
 164	phys_addr_t paddr;
 165	pgprot_t prot;
 166
 167	paddr = PFN_PHYS(pfn);
 168	prot = arch_apei_get_mem_attribute(paddr);
 169	__set_fixmap(fixmap_idx, paddr, prot);
 170
 171	return (void __iomem *) __fix_to_virt(fixmap_idx);
 172}
 173
 174static void ghes_unmap(void __iomem *vaddr, enum fixed_addresses fixmap_idx)
 175{
 176	int _idx = virt_to_fix((unsigned long)vaddr);
 177
 178	WARN_ON_ONCE(fixmap_idx != _idx);
 179	clear_fixmap(fixmap_idx);
 180}
 181
 182int ghes_estatus_pool_init(unsigned int num_ghes)
 183{
 184	unsigned long addr, len;
 185	int rc;
 186
 187	ghes_estatus_pool = gen_pool_create(GHES_ESTATUS_POOL_MIN_ALLOC_ORDER, -1);
 188	if (!ghes_estatus_pool)
 189		return -ENOMEM;
 190
 191	len = GHES_ESTATUS_CACHE_AVG_SIZE * GHES_ESTATUS_CACHE_ALLOCED_MAX;
 192	len += (num_ghes * GHES_ESOURCE_PREALLOC_MAX_SIZE);
 193
 194	ghes_estatus_pool_size_request = PAGE_ALIGN(len);
 195	addr = (unsigned long)vmalloc(PAGE_ALIGN(len));
 196	if (!addr)
 197		goto err_pool_alloc;
 198
 199	rc = gen_pool_add(ghes_estatus_pool, addr, PAGE_ALIGN(len), -1);
 200	if (rc)
 201		goto err_pool_add;
 202
 203	return 0;
 204
 205err_pool_add:
 206	vfree((void *)addr);
 207
 208err_pool_alloc:
 209	gen_pool_destroy(ghes_estatus_pool);
 210
 211	return -ENOMEM;
 212}
 213
 214static int map_gen_v2(struct ghes *ghes)
 215{
 216	return apei_map_generic_address(&ghes->generic_v2->read_ack_register);
 217}
 218
 219static void unmap_gen_v2(struct ghes *ghes)
 220{
 221	apei_unmap_generic_address(&ghes->generic_v2->read_ack_register);
 222}
 223
 224static void ghes_ack_error(struct acpi_hest_generic_v2 *gv2)
 225{
 226	int rc;
 227	u64 val = 0;
 228
 229	rc = apei_read(&val, &gv2->read_ack_register);
 230	if (rc)
 231		return;
 232
 233	val &= gv2->read_ack_preserve << gv2->read_ack_register.bit_offset;
 234	val |= gv2->read_ack_write    << gv2->read_ack_register.bit_offset;
 235
 236	apei_write(val, &gv2->read_ack_register);
 237}
 238
 239static struct ghes *ghes_new(struct acpi_hest_generic *generic)
 240{
 241	struct ghes *ghes;
 242	unsigned int error_block_length;
 243	int rc;
 244
 245	ghes = kzalloc(sizeof(*ghes), GFP_KERNEL);
 246	if (!ghes)
 247		return ERR_PTR(-ENOMEM);
 248
 249	ghes->generic = generic;
 250	if (is_hest_type_generic_v2(ghes)) {
 251		rc = map_gen_v2(ghes);
 252		if (rc)
 253			goto err_free;
 254	}
 255
 256	rc = apei_map_generic_address(&generic->error_status_address);
 257	if (rc)
 258		goto err_unmap_read_ack_addr;
 259	error_block_length = generic->error_block_length;
 260	if (error_block_length > GHES_ESTATUS_MAX_SIZE) {
 261		pr_warn(FW_WARN GHES_PFX
 262			"Error status block length is too long: %u for "
 263			"generic hardware error source: %d.\n",
 264			error_block_length, generic->header.source_id);
 265		error_block_length = GHES_ESTATUS_MAX_SIZE;
 266	}
 267	ghes->estatus = kmalloc(error_block_length, GFP_KERNEL);
 268	if (!ghes->estatus) {
 269		rc = -ENOMEM;
 270		goto err_unmap_status_addr;
 271	}
 272
 273	return ghes;
 274
 275err_unmap_status_addr:
 276	apei_unmap_generic_address(&generic->error_status_address);
 277err_unmap_read_ack_addr:
 278	if (is_hest_type_generic_v2(ghes))
 279		unmap_gen_v2(ghes);
 280err_free:
 281	kfree(ghes);
 282	return ERR_PTR(rc);
 283}
 284
 285static void ghes_fini(struct ghes *ghes)
 286{
 287	kfree(ghes->estatus);
 288	apei_unmap_generic_address(&ghes->generic->error_status_address);
 289	if (is_hest_type_generic_v2(ghes))
 290		unmap_gen_v2(ghes);
 291}
 292
 293static inline int ghes_severity(int severity)
 294{
 295	switch (severity) {
 296	case CPER_SEV_INFORMATIONAL:
 297		return GHES_SEV_NO;
 298	case CPER_SEV_CORRECTED:
 299		return GHES_SEV_CORRECTED;
 300	case CPER_SEV_RECOVERABLE:
 301		return GHES_SEV_RECOVERABLE;
 302	case CPER_SEV_FATAL:
 303		return GHES_SEV_PANIC;
 304	default:
 305		/* Unknown, go panic */
 306		return GHES_SEV_PANIC;
 307	}
 308}
 309
 310static void ghes_copy_tofrom_phys(void *buffer, u64 paddr, u32 len,
 311				  int from_phys,
 312				  enum fixed_addresses fixmap_idx)
 313{
 314	void __iomem *vaddr;
 315	u64 offset;
 316	u32 trunk;
 317
 318	while (len > 0) {
 319		offset = paddr - (paddr & PAGE_MASK);
 320		vaddr = ghes_map(PHYS_PFN(paddr), fixmap_idx);
 321		trunk = PAGE_SIZE - offset;
 322		trunk = min(trunk, len);
 323		if (from_phys)
 324			memcpy_fromio(buffer, vaddr + offset, trunk);
 325		else
 326			memcpy_toio(vaddr + offset, buffer, trunk);
 327		len -= trunk;
 328		paddr += trunk;
 329		buffer += trunk;
 330		ghes_unmap(vaddr, fixmap_idx);
 331	}
 332}
 333
 334/* Check the top-level record header has an appropriate size. */
 335static int __ghes_check_estatus(struct ghes *ghes,
 336				struct acpi_hest_generic_status *estatus)
 337{
 338	u32 len = cper_estatus_len(estatus);
 339
 340	if (len < sizeof(*estatus)) {
 341		pr_warn_ratelimited(FW_WARN GHES_PFX "Truncated error status block!\n");
 342		return -EIO;
 343	}
 344
 345	if (len > ghes->generic->error_block_length) {
 346		pr_warn_ratelimited(FW_WARN GHES_PFX "Invalid error status block length!\n");
 347		return -EIO;
 348	}
 349
 350	if (cper_estatus_check_header(estatus)) {
 351		pr_warn_ratelimited(FW_WARN GHES_PFX "Invalid CPER header!\n");
 352		return -EIO;
 353	}
 354
 355	return 0;
 356}
 357
 358/* Read the CPER block, returning its address, and header in estatus. */
 359static int __ghes_peek_estatus(struct ghes *ghes,
 360			       struct acpi_hest_generic_status *estatus,
 361			       u64 *buf_paddr, enum fixed_addresses fixmap_idx)
 362{
 363	struct acpi_hest_generic *g = ghes->generic;
 364	int rc;
 365
 366	rc = apei_read(buf_paddr, &g->error_status_address);
 367	if (rc) {
 368		*buf_paddr = 0;
 369		pr_warn_ratelimited(FW_WARN GHES_PFX
 370"Failed to read error status block address for hardware error source: %d.\n",
 371				   g->header.source_id);
 372		return -EIO;
 373	}
 374	if (!*buf_paddr)
 375		return -ENOENT;
 376
 377	ghes_copy_tofrom_phys(estatus, *buf_paddr, sizeof(*estatus), 1,
 378			      fixmap_idx);
 379	if (!estatus->block_status) {
 380		*buf_paddr = 0;
 381		return -ENOENT;
 382	}
 383
 384	return 0;
 385}
 386
 387static int __ghes_read_estatus(struct acpi_hest_generic_status *estatus,
 388			       u64 buf_paddr, enum fixed_addresses fixmap_idx,
 389			       size_t buf_len)
 390{
 391	ghes_copy_tofrom_phys(estatus, buf_paddr, buf_len, 1, fixmap_idx);
 392	if (cper_estatus_check(estatus)) {
 393		pr_warn_ratelimited(FW_WARN GHES_PFX
 394				    "Failed to read error status block!\n");
 395		return -EIO;
 396	}
 397
 398	return 0;
 399}
 400
 401static int ghes_read_estatus(struct ghes *ghes,
 402			     struct acpi_hest_generic_status *estatus,
 403			     u64 *buf_paddr, enum fixed_addresses fixmap_idx)
 404{
 405	int rc;
 406
 407	rc = __ghes_peek_estatus(ghes, estatus, buf_paddr, fixmap_idx);
 408	if (rc)
 409		return rc;
 410
 411	rc = __ghes_check_estatus(ghes, estatus);
 412	if (rc)
 413		return rc;
 414
 415	return __ghes_read_estatus(estatus, *buf_paddr, fixmap_idx,
 416				   cper_estatus_len(estatus));
 417}
 418
 419static void ghes_clear_estatus(struct ghes *ghes,
 420			       struct acpi_hest_generic_status *estatus,
 421			       u64 buf_paddr, enum fixed_addresses fixmap_idx)
 422{
 423	estatus->block_status = 0;
 424
 425	if (!buf_paddr)
 426		return;
 427
 428	ghes_copy_tofrom_phys(estatus, buf_paddr,
 429			      sizeof(estatus->block_status), 0,
 430			      fixmap_idx);
 431
 432	/*
 433	 * GHESv2 type HEST entries introduce support for error acknowledgment,
 434	 * so only acknowledge the error if this support is present.
 435	 */
 436	if (is_hest_type_generic_v2(ghes))
 437		ghes_ack_error(ghes->generic_v2);
 438}
 439
 440/*
 441 * Called as task_work before returning to user-space.
 442 * Ensure any queued work has been done before we return to the context that
 443 * triggered the notification.
 444 */
 445static void ghes_kick_task_work(struct callback_head *head)
 446{
 447	struct acpi_hest_generic_status *estatus;
 448	struct ghes_estatus_node *estatus_node;
 449	u32 node_len;
 450
 451	estatus_node = container_of(head, struct ghes_estatus_node, task_work);
 452	if (IS_ENABLED(CONFIG_ACPI_APEI_MEMORY_FAILURE))
 453		memory_failure_queue_kick(estatus_node->task_work_cpu);
 454
 455	estatus = GHES_ESTATUS_FROM_NODE(estatus_node);
 456	node_len = GHES_ESTATUS_NODE_LEN(cper_estatus_len(estatus));
 457	gen_pool_free(ghes_estatus_pool, (unsigned long)estatus_node, node_len);
 458}
 459
 460static bool ghes_do_memory_failure(u64 physical_addr, int flags)
 
 461{
 462	unsigned long pfn;
 
 
 
 463
 464	if (!IS_ENABLED(CONFIG_ACPI_APEI_MEMORY_FAILURE))
 465		return false;
 466
 467	pfn = PHYS_PFN(physical_addr);
 468	if (!pfn_valid(pfn) && !arch_is_platform_page(physical_addr)) {
 
 
 
 469		pr_warn_ratelimited(FW_WARN GHES_PFX
 470		"Invalid address in generic error data: %#llx\n",
 471		physical_addr);
 472		return false;
 473	}
 474
 475	memory_failure_queue(pfn, flags);
 476	return true;
 477}
 478
 479static bool ghes_handle_memory_failure(struct acpi_hest_generic_data *gdata,
 480				       int sev)
 481{
 482	int flags = -1;
 483	int sec_sev = ghes_severity(gdata->error_severity);
 484	struct cper_sec_mem_err *mem_err = acpi_hest_get_payload(gdata);
 485
 486	if (!(mem_err->validation_bits & CPER_MEM_VALID_PA))
 487		return false;
 488
 489	/* iff following two events can be handled properly by now */
 490	if (sec_sev == GHES_SEV_CORRECTED &&
 491	    (gdata->flags & CPER_SEC_ERROR_THRESHOLD_EXCEEDED))
 492		flags = MF_SOFT_OFFLINE;
 493	if (sev == GHES_SEV_RECOVERABLE && sec_sev == GHES_SEV_RECOVERABLE)
 494		flags = 0;
 495
 496	if (flags != -1)
 497		return ghes_do_memory_failure(mem_err->physical_addr, flags);
 
 
 498
 499	return false;
 500}
 501
 502static bool ghes_handle_arm_hw_error(struct acpi_hest_generic_data *gdata, int sev)
 503{
 504	struct cper_sec_proc_arm *err = acpi_hest_get_payload(gdata);
 505	bool queued = false;
 506	int sec_sev, i;
 507	char *p;
 508
 509	log_arm_hw_error(err);
 510
 511	sec_sev = ghes_severity(gdata->error_severity);
 512	if (sev != GHES_SEV_RECOVERABLE || sec_sev != GHES_SEV_RECOVERABLE)
 513		return false;
 514
 515	p = (char *)(err + 1);
 516	for (i = 0; i < err->err_info_num; i++) {
 517		struct cper_arm_err_info *err_info = (struct cper_arm_err_info *)p;
 518		bool is_cache = (err_info->type == CPER_ARM_CACHE_ERROR);
 519		bool has_pa = (err_info->validation_bits & CPER_ARM_INFO_VALID_PHYSICAL_ADDR);
 520		const char *error_type = "unknown error";
 521
 522		/*
 523		 * The field (err_info->error_info & BIT(26)) is fixed to set to
 524		 * 1 in some old firmware of HiSilicon Kunpeng920. We assume that
 525		 * firmware won't mix corrected errors in an uncorrected section,
 526		 * and don't filter out 'corrected' error here.
 527		 */
 528		if (is_cache && has_pa) {
 529			queued = ghes_do_memory_failure(err_info->physical_fault_addr, 0);
 530			p += err_info->length;
 531			continue;
 532		}
 533
 534		if (err_info->type < ARRAY_SIZE(cper_proc_error_type_strs))
 535			error_type = cper_proc_error_type_strs[err_info->type];
 536
 537		pr_warn_ratelimited(FW_WARN GHES_PFX
 538				    "Unhandled processor error type: %s\n",
 539				    error_type);
 540		p += err_info->length;
 541	}
 542
 543	return queued;
 544}
 545
 546/*
 547 * PCIe AER errors need to be sent to the AER driver for reporting and
 548 * recovery. The GHES severities map to the following AER severities and
 549 * require the following handling:
 550 *
 551 * GHES_SEV_CORRECTABLE -> AER_CORRECTABLE
 552 *     These need to be reported by the AER driver but no recovery is
 553 *     necessary.
 554 * GHES_SEV_RECOVERABLE -> AER_NONFATAL
 555 * GHES_SEV_RECOVERABLE && CPER_SEC_RESET -> AER_FATAL
 556 *     These both need to be reported and recovered from by the AER driver.
 557 * GHES_SEV_PANIC does not make it to this handling since the kernel must
 558 *     panic.
 559 */
 560static void ghes_handle_aer(struct acpi_hest_generic_data *gdata)
 561{
 562#ifdef CONFIG_ACPI_APEI_PCIEAER
 563	struct cper_sec_pcie *pcie_err = acpi_hest_get_payload(gdata);
 564
 565	if (pcie_err->validation_bits & CPER_PCIE_VALID_DEVICE_ID &&
 566	    pcie_err->validation_bits & CPER_PCIE_VALID_AER_INFO) {
 567		unsigned int devfn;
 568		int aer_severity;
 569
 570		devfn = PCI_DEVFN(pcie_err->device_id.device,
 571				  pcie_err->device_id.function);
 572		aer_severity = cper_severity_to_aer(gdata->error_severity);
 573
 574		/*
 575		 * If firmware reset the component to contain
 576		 * the error, we must reinitialize it before
 577		 * use, so treat it as a fatal AER error.
 578		 */
 579		if (gdata->flags & CPER_SEC_RESET)
 580			aer_severity = AER_FATAL;
 581
 582		aer_recover_queue(pcie_err->device_id.segment,
 583				  pcie_err->device_id.bus,
 584				  devfn, aer_severity,
 585				  (struct aer_capability_regs *)
 586				  pcie_err->aer_info);
 587	}
 588#endif
 589}
 590
 591static BLOCKING_NOTIFIER_HEAD(vendor_record_notify_list);
 592
 593int ghes_register_vendor_record_notifier(struct notifier_block *nb)
 594{
 595	return blocking_notifier_chain_register(&vendor_record_notify_list, nb);
 596}
 597EXPORT_SYMBOL_GPL(ghes_register_vendor_record_notifier);
 598
 599void ghes_unregister_vendor_record_notifier(struct notifier_block *nb)
 600{
 601	blocking_notifier_chain_unregister(&vendor_record_notify_list, nb);
 602}
 603EXPORT_SYMBOL_GPL(ghes_unregister_vendor_record_notifier);
 604
 605static void ghes_vendor_record_work_func(struct work_struct *work)
 606{
 607	struct ghes_vendor_record_entry *entry;
 608	struct acpi_hest_generic_data *gdata;
 609	u32 len;
 610
 611	entry = container_of(work, struct ghes_vendor_record_entry, work);
 612	gdata = GHES_GDATA_FROM_VENDOR_ENTRY(entry);
 613
 614	blocking_notifier_call_chain(&vendor_record_notify_list,
 615				     entry->error_severity, gdata);
 616
 617	len = GHES_VENDOR_ENTRY_LEN(acpi_hest_get_record_size(gdata));
 618	gen_pool_free(ghes_estatus_pool, (unsigned long)entry, len);
 619}
 620
 621static void ghes_defer_non_standard_event(struct acpi_hest_generic_data *gdata,
 622					  int sev)
 623{
 624	struct acpi_hest_generic_data *copied_gdata;
 625	struct ghes_vendor_record_entry *entry;
 626	u32 len;
 627
 628	len = GHES_VENDOR_ENTRY_LEN(acpi_hest_get_record_size(gdata));
 629	entry = (void *)gen_pool_alloc(ghes_estatus_pool, len);
 630	if (!entry)
 631		return;
 632
 633	copied_gdata = GHES_GDATA_FROM_VENDOR_ENTRY(entry);
 634	memcpy(copied_gdata, gdata, acpi_hest_get_record_size(gdata));
 635	entry->error_severity = sev;
 636
 637	INIT_WORK(&entry->work, ghes_vendor_record_work_func);
 638	schedule_work(&entry->work);
 639}
 640
 641static bool ghes_do_proc(struct ghes *ghes,
 642			 const struct acpi_hest_generic_status *estatus)
 643{
 644	int sev, sec_sev;
 645	struct acpi_hest_generic_data *gdata;
 646	guid_t *sec_type;
 647	const guid_t *fru_id = &guid_null;
 648	char *fru_text = "";
 649	bool queued = false;
 650
 651	sev = ghes_severity(estatus->error_severity);
 652	apei_estatus_for_each_section(estatus, gdata) {
 653		sec_type = (guid_t *)gdata->section_type;
 654		sec_sev = ghes_severity(gdata->error_severity);
 655		if (gdata->validation_bits & CPER_SEC_VALID_FRU_ID)
 656			fru_id = (guid_t *)gdata->fru_id;
 657
 658		if (gdata->validation_bits & CPER_SEC_VALID_FRU_TEXT)
 659			fru_text = gdata->fru_text;
 660
 661		if (guid_equal(sec_type, &CPER_SEC_PLATFORM_MEM)) {
 662			struct cper_sec_mem_err *mem_err = acpi_hest_get_payload(gdata);
 663
 664			atomic_notifier_call_chain(&ghes_report_chain, sev, mem_err);
 665
 666			arch_apei_report_mem_error(sev, mem_err);
 667			queued = ghes_handle_memory_failure(gdata, sev);
 668		}
 669		else if (guid_equal(sec_type, &CPER_SEC_PCIE)) {
 670			ghes_handle_aer(gdata);
 671		}
 672		else if (guid_equal(sec_type, &CPER_SEC_PROC_ARM)) {
 673			queued = ghes_handle_arm_hw_error(gdata, sev);
 
 
 674		} else {
 675			void *err = acpi_hest_get_payload(gdata);
 676
 677			ghes_defer_non_standard_event(gdata, sev);
 678			log_non_standard_event(sec_type, fru_id, fru_text,
 679					       sec_sev, err,
 680					       gdata->error_data_length);
 681		}
 682	}
 683
 684	return queued;
 685}
 686
 687static void __ghes_print_estatus(const char *pfx,
 688				 const struct acpi_hest_generic *generic,
 689				 const struct acpi_hest_generic_status *estatus)
 690{
 691	static atomic_t seqno;
 692	unsigned int curr_seqno;
 693	char pfx_seq[64];
 694
 695	if (pfx == NULL) {
 696		if (ghes_severity(estatus->error_severity) <=
 697		    GHES_SEV_CORRECTED)
 698			pfx = KERN_WARNING;
 699		else
 700			pfx = KERN_ERR;
 701	}
 702	curr_seqno = atomic_inc_return(&seqno);
 703	snprintf(pfx_seq, sizeof(pfx_seq), "%s{%u}" HW_ERR, pfx, curr_seqno);
 704	printk("%s""Hardware error from APEI Generic Hardware Error Source: %d\n",
 705	       pfx_seq, generic->header.source_id);
 706	cper_estatus_print(pfx_seq, estatus);
 707}
 708
 709static int ghes_print_estatus(const char *pfx,
 710			      const struct acpi_hest_generic *generic,
 711			      const struct acpi_hest_generic_status *estatus)
 712{
 713	/* Not more than 2 messages every 5 seconds */
 714	static DEFINE_RATELIMIT_STATE(ratelimit_corrected, 5*HZ, 2);
 715	static DEFINE_RATELIMIT_STATE(ratelimit_uncorrected, 5*HZ, 2);
 716	struct ratelimit_state *ratelimit;
 717
 718	if (ghes_severity(estatus->error_severity) <= GHES_SEV_CORRECTED)
 719		ratelimit = &ratelimit_corrected;
 720	else
 721		ratelimit = &ratelimit_uncorrected;
 722	if (__ratelimit(ratelimit)) {
 723		__ghes_print_estatus(pfx, generic, estatus);
 724		return 1;
 725	}
 726	return 0;
 727}
 728
 729/*
 730 * GHES error status reporting throttle, to report more kinds of
 731 * errors, instead of just most frequently occurred errors.
 732 */
 733static int ghes_estatus_cached(struct acpi_hest_generic_status *estatus)
 734{
 735	u32 len;
 736	int i, cached = 0;
 737	unsigned long long now;
 738	struct ghes_estatus_cache *cache;
 739	struct acpi_hest_generic_status *cache_estatus;
 740
 741	len = cper_estatus_len(estatus);
 742	rcu_read_lock();
 743	for (i = 0; i < GHES_ESTATUS_CACHES_SIZE; i++) {
 744		cache = rcu_dereference(ghes_estatus_caches[i]);
 745		if (cache == NULL)
 746			continue;
 747		if (len != cache->estatus_len)
 748			continue;
 749		cache_estatus = GHES_ESTATUS_FROM_CACHE(cache);
 750		if (memcmp(estatus, cache_estatus, len))
 751			continue;
 752		atomic_inc(&cache->count);
 753		now = sched_clock();
 754		if (now - cache->time_in < GHES_ESTATUS_IN_CACHE_MAX_NSEC)
 755			cached = 1;
 756		break;
 757	}
 758	rcu_read_unlock();
 759	return cached;
 760}
 761
 762static struct ghes_estatus_cache *ghes_estatus_cache_alloc(
 763	struct acpi_hest_generic *generic,
 764	struct acpi_hest_generic_status *estatus)
 765{
 766	int alloced;
 767	u32 len, cache_len;
 768	struct ghes_estatus_cache *cache;
 769	struct acpi_hest_generic_status *cache_estatus;
 770
 771	alloced = atomic_add_return(1, &ghes_estatus_cache_alloced);
 772	if (alloced > GHES_ESTATUS_CACHE_ALLOCED_MAX) {
 773		atomic_dec(&ghes_estatus_cache_alloced);
 774		return NULL;
 775	}
 776	len = cper_estatus_len(estatus);
 777	cache_len = GHES_ESTATUS_CACHE_LEN(len);
 778	cache = (void *)gen_pool_alloc(ghes_estatus_pool, cache_len);
 779	if (!cache) {
 780		atomic_dec(&ghes_estatus_cache_alloced);
 781		return NULL;
 782	}
 783	cache_estatus = GHES_ESTATUS_FROM_CACHE(cache);
 784	memcpy(cache_estatus, estatus, len);
 785	cache->estatus_len = len;
 786	atomic_set(&cache->count, 0);
 787	cache->generic = generic;
 788	cache->time_in = sched_clock();
 789	return cache;
 790}
 791
 792static void ghes_estatus_cache_rcu_free(struct rcu_head *head)
 793{
 794	struct ghes_estatus_cache *cache;
 795	u32 len;
 796
 797	cache = container_of(head, struct ghes_estatus_cache, rcu);
 798	len = cper_estatus_len(GHES_ESTATUS_FROM_CACHE(cache));
 799	len = GHES_ESTATUS_CACHE_LEN(len);
 800	gen_pool_free(ghes_estatus_pool, (unsigned long)cache, len);
 801	atomic_dec(&ghes_estatus_cache_alloced);
 802}
 803
 804static void
 805ghes_estatus_cache_add(struct acpi_hest_generic *generic,
 806		       struct acpi_hest_generic_status *estatus)
 
 
 
 
 
 
 
 
 807{
 
 808	unsigned long long now, duration, period, max_period = 0;
 809	struct ghes_estatus_cache *cache, *new_cache;
 810	struct ghes_estatus_cache __rcu *victim;
 811	int i, slot = -1, count;
 812
 813	new_cache = ghes_estatus_cache_alloc(generic, estatus);
 814	if (!new_cache)
 815		return;
 816
 817	rcu_read_lock();
 818	now = sched_clock();
 819	for (i = 0; i < GHES_ESTATUS_CACHES_SIZE; i++) {
 820		cache = rcu_dereference(ghes_estatus_caches[i]);
 821		if (cache == NULL) {
 822			slot = i;
 
 823			break;
 824		}
 825		duration = now - cache->time_in;
 826		if (duration >= GHES_ESTATUS_IN_CACHE_MAX_NSEC) {
 827			slot = i;
 
 828			break;
 829		}
 830		count = atomic_read(&cache->count);
 831		period = duration;
 832		do_div(period, (count + 1));
 833		if (period > max_period) {
 834			max_period = period;
 835			slot = i;
 
 836		}
 837	}
 
 
 
 
 
 
 
 
 838	rcu_read_unlock();
 839
 840	if (slot != -1) {
 841		/*
 842		 * Use release semantics to ensure that ghes_estatus_cached()
 843		 * running on another CPU will see the updated cache fields if
 844		 * it can see the new value of the pointer.
 845		 */
 846		victim = xchg_release(&ghes_estatus_caches[slot],
 847				      RCU_INITIALIZER(new_cache));
 848
 849		/*
 850		 * At this point, victim may point to a cached item different
 851		 * from the one based on which we selected the slot. Instead of
 852		 * going to the loop again to pick another slot, let's just
 853		 * drop the other item anyway: this may cause a false cache
 854		 * miss later on, but that won't cause any problems.
 855		 */
 856		if (victim)
 857			call_rcu(&unrcu_pointer(victim)->rcu,
 858				 ghes_estatus_cache_rcu_free);
 859	}
 860}
 861
 862static void __ghes_panic(struct ghes *ghes,
 863			 struct acpi_hest_generic_status *estatus,
 864			 u64 buf_paddr, enum fixed_addresses fixmap_idx)
 865{
 866	__ghes_print_estatus(KERN_EMERG, ghes->generic, estatus);
 867
 868	ghes_clear_estatus(ghes, estatus, buf_paddr, fixmap_idx);
 869
 870	/* reboot to log the error! */
 871	if (!panic_timeout)
 872		panic_timeout = ghes_panic_timeout;
 873	panic("Fatal hardware error!");
 874}
 875
 876static int ghes_proc(struct ghes *ghes)
 877{
 878	struct acpi_hest_generic_status *estatus = ghes->estatus;
 879	u64 buf_paddr;
 880	int rc;
 881
 882	rc = ghes_read_estatus(ghes, estatus, &buf_paddr, FIX_APEI_GHES_IRQ);
 883	if (rc)
 884		goto out;
 885
 886	if (ghes_severity(estatus->error_severity) >= GHES_SEV_PANIC)
 887		__ghes_panic(ghes, estatus, buf_paddr, FIX_APEI_GHES_IRQ);
 888
 889	if (!ghes_estatus_cached(estatus)) {
 890		if (ghes_print_estatus(NULL, ghes->generic, estatus))
 891			ghes_estatus_cache_add(ghes->generic, estatus);
 892	}
 893	ghes_do_proc(ghes, estatus);
 894
 895out:
 896	ghes_clear_estatus(ghes, estatus, buf_paddr, FIX_APEI_GHES_IRQ);
 897
 898	return rc;
 899}
 900
 901static void ghes_add_timer(struct ghes *ghes)
 902{
 903	struct acpi_hest_generic *g = ghes->generic;
 904	unsigned long expire;
 905
 906	if (!g->notify.poll_interval) {
 907		pr_warn(FW_WARN GHES_PFX "Poll interval is 0 for generic hardware error source: %d, disabled.\n",
 908			g->header.source_id);
 909		return;
 910	}
 911	expire = jiffies + msecs_to_jiffies(g->notify.poll_interval);
 912	ghes->timer.expires = round_jiffies_relative(expire);
 913	add_timer(&ghes->timer);
 914}
 915
 916static void ghes_poll_func(struct timer_list *t)
 917{
 918	struct ghes *ghes = from_timer(ghes, t, timer);
 919	unsigned long flags;
 920
 921	spin_lock_irqsave(&ghes_notify_lock_irq, flags);
 922	ghes_proc(ghes);
 923	spin_unlock_irqrestore(&ghes_notify_lock_irq, flags);
 924	if (!(ghes->flags & GHES_EXITING))
 925		ghes_add_timer(ghes);
 926}
 927
 928static irqreturn_t ghes_irq_func(int irq, void *data)
 929{
 930	struct ghes *ghes = data;
 931	unsigned long flags;
 932	int rc;
 933
 934	spin_lock_irqsave(&ghes_notify_lock_irq, flags);
 935	rc = ghes_proc(ghes);
 936	spin_unlock_irqrestore(&ghes_notify_lock_irq, flags);
 937	if (rc)
 938		return IRQ_NONE;
 939
 940	return IRQ_HANDLED;
 941}
 942
 943static int ghes_notify_hed(struct notifier_block *this, unsigned long event,
 944			   void *data)
 945{
 946	struct ghes *ghes;
 947	unsigned long flags;
 948	int ret = NOTIFY_DONE;
 949
 950	spin_lock_irqsave(&ghes_notify_lock_irq, flags);
 951	rcu_read_lock();
 952	list_for_each_entry_rcu(ghes, &ghes_hed, list) {
 953		if (!ghes_proc(ghes))
 954			ret = NOTIFY_OK;
 955	}
 956	rcu_read_unlock();
 957	spin_unlock_irqrestore(&ghes_notify_lock_irq, flags);
 958
 959	return ret;
 960}
 961
 962static struct notifier_block ghes_notifier_hed = {
 963	.notifier_call = ghes_notify_hed,
 964};
 965
 966/*
 967 * Handlers for CPER records may not be NMI safe. For example,
 968 * memory_failure_queue() takes spinlocks and calls schedule_work_on().
 969 * In any NMI-like handler, memory from ghes_estatus_pool is used to save
 970 * estatus, and added to the ghes_estatus_llist. irq_work_queue() causes
 971 * ghes_proc_in_irq() to run in IRQ context where each estatus in
 972 * ghes_estatus_llist is processed.
 973 *
 974 * Memory from the ghes_estatus_pool is also used with the ghes_estatus_cache
 975 * to suppress frequent messages.
 976 */
 977static struct llist_head ghes_estatus_llist;
 978static struct irq_work ghes_proc_irq_work;
 979
 980static void ghes_proc_in_irq(struct irq_work *irq_work)
 981{
 982	struct llist_node *llnode, *next;
 983	struct ghes_estatus_node *estatus_node;
 984	struct acpi_hest_generic *generic;
 985	struct acpi_hest_generic_status *estatus;
 986	bool task_work_pending;
 987	u32 len, node_len;
 988	int ret;
 989
 990	llnode = llist_del_all(&ghes_estatus_llist);
 991	/*
 992	 * Because the time order of estatus in list is reversed,
 993	 * revert it back to proper order.
 994	 */
 995	llnode = llist_reverse_order(llnode);
 996	while (llnode) {
 997		next = llnode->next;
 998		estatus_node = llist_entry(llnode, struct ghes_estatus_node,
 999					   llnode);
1000		estatus = GHES_ESTATUS_FROM_NODE(estatus_node);
1001		len = cper_estatus_len(estatus);
1002		node_len = GHES_ESTATUS_NODE_LEN(len);
1003		task_work_pending = ghes_do_proc(estatus_node->ghes, estatus);
1004		if (!ghes_estatus_cached(estatus)) {
1005			generic = estatus_node->generic;
1006			if (ghes_print_estatus(NULL, generic, estatus))
1007				ghes_estatus_cache_add(generic, estatus);
1008		}
1009
1010		if (task_work_pending && current->mm) {
1011			estatus_node->task_work.func = ghes_kick_task_work;
1012			estatus_node->task_work_cpu = smp_processor_id();
1013			ret = task_work_add(current, &estatus_node->task_work,
1014					    TWA_RESUME);
1015			if (ret)
1016				estatus_node->task_work.func = NULL;
1017		}
1018
1019		if (!estatus_node->task_work.func)
1020			gen_pool_free(ghes_estatus_pool,
1021				      (unsigned long)estatus_node, node_len);
1022
1023		llnode = next;
1024	}
1025}
1026
1027static void ghes_print_queued_estatus(void)
1028{
1029	struct llist_node *llnode;
1030	struct ghes_estatus_node *estatus_node;
1031	struct acpi_hest_generic *generic;
1032	struct acpi_hest_generic_status *estatus;
1033
1034	llnode = llist_del_all(&ghes_estatus_llist);
1035	/*
1036	 * Because the time order of estatus in list is reversed,
1037	 * revert it back to proper order.
1038	 */
1039	llnode = llist_reverse_order(llnode);
1040	while (llnode) {
1041		estatus_node = llist_entry(llnode, struct ghes_estatus_node,
1042					   llnode);
1043		estatus = GHES_ESTATUS_FROM_NODE(estatus_node);
1044		generic = estatus_node->generic;
1045		ghes_print_estatus(NULL, generic, estatus);
1046		llnode = llnode->next;
1047	}
1048}
1049
1050static int ghes_in_nmi_queue_one_entry(struct ghes *ghes,
1051				       enum fixed_addresses fixmap_idx)
1052{
1053	struct acpi_hest_generic_status *estatus, tmp_header;
1054	struct ghes_estatus_node *estatus_node;
1055	u32 len, node_len;
1056	u64 buf_paddr;
1057	int sev, rc;
1058
1059	if (!IS_ENABLED(CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG))
1060		return -EOPNOTSUPP;
1061
1062	rc = __ghes_peek_estatus(ghes, &tmp_header, &buf_paddr, fixmap_idx);
1063	if (rc) {
1064		ghes_clear_estatus(ghes, &tmp_header, buf_paddr, fixmap_idx);
1065		return rc;
1066	}
1067
1068	rc = __ghes_check_estatus(ghes, &tmp_header);
1069	if (rc) {
1070		ghes_clear_estatus(ghes, &tmp_header, buf_paddr, fixmap_idx);
1071		return rc;
1072	}
1073
1074	len = cper_estatus_len(&tmp_header);
1075	node_len = GHES_ESTATUS_NODE_LEN(len);
1076	estatus_node = (void *)gen_pool_alloc(ghes_estatus_pool, node_len);
1077	if (!estatus_node)
1078		return -ENOMEM;
1079
1080	estatus_node->ghes = ghes;
1081	estatus_node->generic = ghes->generic;
1082	estatus_node->task_work.func = NULL;
1083	estatus = GHES_ESTATUS_FROM_NODE(estatus_node);
1084
1085	if (__ghes_read_estatus(estatus, buf_paddr, fixmap_idx, len)) {
1086		ghes_clear_estatus(ghes, estatus, buf_paddr, fixmap_idx);
1087		rc = -ENOENT;
1088		goto no_work;
1089	}
1090
1091	sev = ghes_severity(estatus->error_severity);
1092	if (sev >= GHES_SEV_PANIC) {
1093		ghes_print_queued_estatus();
1094		__ghes_panic(ghes, estatus, buf_paddr, fixmap_idx);
1095	}
1096
1097	ghes_clear_estatus(ghes, &tmp_header, buf_paddr, fixmap_idx);
1098
1099	/* This error has been reported before, don't process it again. */
1100	if (ghes_estatus_cached(estatus))
1101		goto no_work;
1102
1103	llist_add(&estatus_node->llnode, &ghes_estatus_llist);
1104
1105	return rc;
1106
1107no_work:
1108	gen_pool_free(ghes_estatus_pool, (unsigned long)estatus_node,
1109		      node_len);
1110
1111	return rc;
1112}
1113
1114static int ghes_in_nmi_spool_from_list(struct list_head *rcu_list,
1115				       enum fixed_addresses fixmap_idx)
1116{
1117	int ret = -ENOENT;
1118	struct ghes *ghes;
1119
1120	rcu_read_lock();
1121	list_for_each_entry_rcu(ghes, rcu_list, list) {
1122		if (!ghes_in_nmi_queue_one_entry(ghes, fixmap_idx))
1123			ret = 0;
1124	}
1125	rcu_read_unlock();
1126
1127	if (IS_ENABLED(CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG) && !ret)
1128		irq_work_queue(&ghes_proc_irq_work);
1129
1130	return ret;
1131}
1132
1133#ifdef CONFIG_ACPI_APEI_SEA
1134static LIST_HEAD(ghes_sea);
1135
1136/*
1137 * Return 0 only if one of the SEA error sources successfully reported an error
1138 * record sent from the firmware.
1139 */
1140int ghes_notify_sea(void)
1141{
1142	static DEFINE_RAW_SPINLOCK(ghes_notify_lock_sea);
1143	int rv;
1144
1145	raw_spin_lock(&ghes_notify_lock_sea);
1146	rv = ghes_in_nmi_spool_from_list(&ghes_sea, FIX_APEI_GHES_SEA);
1147	raw_spin_unlock(&ghes_notify_lock_sea);
1148
1149	return rv;
1150}
1151
1152static void ghes_sea_add(struct ghes *ghes)
1153{
1154	mutex_lock(&ghes_list_mutex);
1155	list_add_rcu(&ghes->list, &ghes_sea);
1156	mutex_unlock(&ghes_list_mutex);
1157}
1158
1159static void ghes_sea_remove(struct ghes *ghes)
1160{
1161	mutex_lock(&ghes_list_mutex);
1162	list_del_rcu(&ghes->list);
1163	mutex_unlock(&ghes_list_mutex);
1164	synchronize_rcu();
1165}
1166#else /* CONFIG_ACPI_APEI_SEA */
1167static inline void ghes_sea_add(struct ghes *ghes) { }
1168static inline void ghes_sea_remove(struct ghes *ghes) { }
1169#endif /* CONFIG_ACPI_APEI_SEA */
1170
1171#ifdef CONFIG_HAVE_ACPI_APEI_NMI
1172/*
1173 * NMI may be triggered on any CPU, so ghes_in_nmi is used for
1174 * having only one concurrent reader.
1175 */
1176static atomic_t ghes_in_nmi = ATOMIC_INIT(0);
1177
1178static LIST_HEAD(ghes_nmi);
1179
1180static int ghes_notify_nmi(unsigned int cmd, struct pt_regs *regs)
1181{
1182	static DEFINE_RAW_SPINLOCK(ghes_notify_lock_nmi);
1183	int ret = NMI_DONE;
1184
1185	if (!atomic_add_unless(&ghes_in_nmi, 1, 1))
1186		return ret;
1187
1188	raw_spin_lock(&ghes_notify_lock_nmi);
1189	if (!ghes_in_nmi_spool_from_list(&ghes_nmi, FIX_APEI_GHES_NMI))
1190		ret = NMI_HANDLED;
1191	raw_spin_unlock(&ghes_notify_lock_nmi);
1192
1193	atomic_dec(&ghes_in_nmi);
1194	return ret;
1195}
1196
1197static void ghes_nmi_add(struct ghes *ghes)
1198{
1199	mutex_lock(&ghes_list_mutex);
1200	if (list_empty(&ghes_nmi))
1201		register_nmi_handler(NMI_LOCAL, ghes_notify_nmi, 0, "ghes");
1202	list_add_rcu(&ghes->list, &ghes_nmi);
1203	mutex_unlock(&ghes_list_mutex);
1204}
1205
1206static void ghes_nmi_remove(struct ghes *ghes)
1207{
1208	mutex_lock(&ghes_list_mutex);
1209	list_del_rcu(&ghes->list);
1210	if (list_empty(&ghes_nmi))
1211		unregister_nmi_handler(NMI_LOCAL, "ghes");
1212	mutex_unlock(&ghes_list_mutex);
1213	/*
1214	 * To synchronize with NMI handler, ghes can only be
1215	 * freed after NMI handler finishes.
1216	 */
1217	synchronize_rcu();
1218}
1219#else /* CONFIG_HAVE_ACPI_APEI_NMI */
1220static inline void ghes_nmi_add(struct ghes *ghes) { }
1221static inline void ghes_nmi_remove(struct ghes *ghes) { }
1222#endif /* CONFIG_HAVE_ACPI_APEI_NMI */
1223
1224static void ghes_nmi_init_cxt(void)
1225{
1226	init_irq_work(&ghes_proc_irq_work, ghes_proc_in_irq);
1227}
1228
1229static int __ghes_sdei_callback(struct ghes *ghes,
1230				enum fixed_addresses fixmap_idx)
1231{
1232	if (!ghes_in_nmi_queue_one_entry(ghes, fixmap_idx)) {
1233		irq_work_queue(&ghes_proc_irq_work);
1234
1235		return 0;
1236	}
1237
1238	return -ENOENT;
1239}
1240
1241static int ghes_sdei_normal_callback(u32 event_num, struct pt_regs *regs,
1242				      void *arg)
1243{
1244	static DEFINE_RAW_SPINLOCK(ghes_notify_lock_sdei_normal);
1245	struct ghes *ghes = arg;
1246	int err;
1247
1248	raw_spin_lock(&ghes_notify_lock_sdei_normal);
1249	err = __ghes_sdei_callback(ghes, FIX_APEI_GHES_SDEI_NORMAL);
1250	raw_spin_unlock(&ghes_notify_lock_sdei_normal);
1251
1252	return err;
1253}
1254
1255static int ghes_sdei_critical_callback(u32 event_num, struct pt_regs *regs,
1256				       void *arg)
1257{
1258	static DEFINE_RAW_SPINLOCK(ghes_notify_lock_sdei_critical);
1259	struct ghes *ghes = arg;
1260	int err;
1261
1262	raw_spin_lock(&ghes_notify_lock_sdei_critical);
1263	err = __ghes_sdei_callback(ghes, FIX_APEI_GHES_SDEI_CRITICAL);
1264	raw_spin_unlock(&ghes_notify_lock_sdei_critical);
1265
1266	return err;
1267}
1268
1269static int apei_sdei_register_ghes(struct ghes *ghes)
1270{
1271	if (!IS_ENABLED(CONFIG_ARM_SDE_INTERFACE))
1272		return -EOPNOTSUPP;
1273
1274	return sdei_register_ghes(ghes, ghes_sdei_normal_callback,
1275				 ghes_sdei_critical_callback);
1276}
1277
1278static int apei_sdei_unregister_ghes(struct ghes *ghes)
1279{
1280	if (!IS_ENABLED(CONFIG_ARM_SDE_INTERFACE))
1281		return -EOPNOTSUPP;
1282
1283	return sdei_unregister_ghes(ghes);
1284}
1285
1286static int ghes_probe(struct platform_device *ghes_dev)
1287{
1288	struct acpi_hest_generic *generic;
1289	struct ghes *ghes = NULL;
1290	unsigned long flags;
1291
1292	int rc = -EINVAL;
1293
1294	generic = *(struct acpi_hest_generic **)ghes_dev->dev.platform_data;
1295	if (!generic->enabled)
1296		return -ENODEV;
1297
1298	switch (generic->notify.type) {
1299	case ACPI_HEST_NOTIFY_POLLED:
1300	case ACPI_HEST_NOTIFY_EXTERNAL:
1301	case ACPI_HEST_NOTIFY_SCI:
1302	case ACPI_HEST_NOTIFY_GSIV:
1303	case ACPI_HEST_NOTIFY_GPIO:
1304		break;
1305
1306	case ACPI_HEST_NOTIFY_SEA:
1307		if (!IS_ENABLED(CONFIG_ACPI_APEI_SEA)) {
1308			pr_warn(GHES_PFX "Generic hardware error source: %d notified via SEA is not supported\n",
1309				generic->header.source_id);
1310			rc = -ENOTSUPP;
1311			goto err;
1312		}
1313		break;
1314	case ACPI_HEST_NOTIFY_NMI:
1315		if (!IS_ENABLED(CONFIG_HAVE_ACPI_APEI_NMI)) {
1316			pr_warn(GHES_PFX "Generic hardware error source: %d notified via NMI interrupt is not supported!\n",
1317				generic->header.source_id);
1318			goto err;
1319		}
1320		break;
1321	case ACPI_HEST_NOTIFY_SOFTWARE_DELEGATED:
1322		if (!IS_ENABLED(CONFIG_ARM_SDE_INTERFACE)) {
1323			pr_warn(GHES_PFX "Generic hardware error source: %d notified via SDE Interface is not supported!\n",
1324				generic->header.source_id);
1325			goto err;
1326		}
1327		break;
1328	case ACPI_HEST_NOTIFY_LOCAL:
1329		pr_warn(GHES_PFX "Generic hardware error source: %d notified via local interrupt is not supported!\n",
1330			generic->header.source_id);
1331		goto err;
1332	default:
1333		pr_warn(FW_WARN GHES_PFX "Unknown notification type: %u for generic hardware error source: %d\n",
1334			generic->notify.type, generic->header.source_id);
1335		goto err;
1336	}
1337
1338	rc = -EIO;
1339	if (generic->error_block_length <
1340	    sizeof(struct acpi_hest_generic_status)) {
1341		pr_warn(FW_BUG GHES_PFX "Invalid error block length: %u for generic hardware error source: %d\n",
1342			generic->error_block_length, generic->header.source_id);
1343		goto err;
1344	}
1345	ghes = ghes_new(generic);
1346	if (IS_ERR(ghes)) {
1347		rc = PTR_ERR(ghes);
1348		ghes = NULL;
1349		goto err;
1350	}
1351
1352	switch (generic->notify.type) {
1353	case ACPI_HEST_NOTIFY_POLLED:
1354		timer_setup(&ghes->timer, ghes_poll_func, 0);
1355		ghes_add_timer(ghes);
1356		break;
1357	case ACPI_HEST_NOTIFY_EXTERNAL:
1358		/* External interrupt vector is GSI */
1359		rc = acpi_gsi_to_irq(generic->notify.vector, &ghes->irq);
1360		if (rc) {
1361			pr_err(GHES_PFX "Failed to map GSI to IRQ for generic hardware error source: %d\n",
1362			       generic->header.source_id);
1363			goto err;
1364		}
1365		rc = request_irq(ghes->irq, ghes_irq_func, IRQF_SHARED,
1366				 "GHES IRQ", ghes);
1367		if (rc) {
1368			pr_err(GHES_PFX "Failed to register IRQ for generic hardware error source: %d\n",
1369			       generic->header.source_id);
1370			goto err;
1371		}
1372		break;
1373
1374	case ACPI_HEST_NOTIFY_SCI:
1375	case ACPI_HEST_NOTIFY_GSIV:
1376	case ACPI_HEST_NOTIFY_GPIO:
1377		mutex_lock(&ghes_list_mutex);
1378		if (list_empty(&ghes_hed))
1379			register_acpi_hed_notifier(&ghes_notifier_hed);
1380		list_add_rcu(&ghes->list, &ghes_hed);
1381		mutex_unlock(&ghes_list_mutex);
1382		break;
1383
1384	case ACPI_HEST_NOTIFY_SEA:
1385		ghes_sea_add(ghes);
1386		break;
1387	case ACPI_HEST_NOTIFY_NMI:
1388		ghes_nmi_add(ghes);
1389		break;
1390	case ACPI_HEST_NOTIFY_SOFTWARE_DELEGATED:
1391		rc = apei_sdei_register_ghes(ghes);
1392		if (rc)
1393			goto err;
1394		break;
1395	default:
1396		BUG();
1397	}
1398
1399	platform_set_drvdata(ghes_dev, ghes);
1400
1401	ghes->dev = &ghes_dev->dev;
1402
1403	mutex_lock(&ghes_devs_mutex);
1404	list_add_tail(&ghes->elist, &ghes_devs);
1405	mutex_unlock(&ghes_devs_mutex);
1406
1407	/* Handle any pending errors right away */
1408	spin_lock_irqsave(&ghes_notify_lock_irq, flags);
1409	ghes_proc(ghes);
1410	spin_unlock_irqrestore(&ghes_notify_lock_irq, flags);
1411
1412	return 0;
1413
1414err:
1415	if (ghes) {
1416		ghes_fini(ghes);
1417		kfree(ghes);
1418	}
1419	return rc;
1420}
1421
1422static int ghes_remove(struct platform_device *ghes_dev)
1423{
1424	int rc;
1425	struct ghes *ghes;
1426	struct acpi_hest_generic *generic;
1427
1428	ghes = platform_get_drvdata(ghes_dev);
1429	generic = ghes->generic;
1430
1431	ghes->flags |= GHES_EXITING;
1432	switch (generic->notify.type) {
1433	case ACPI_HEST_NOTIFY_POLLED:
1434		timer_shutdown_sync(&ghes->timer);
1435		break;
1436	case ACPI_HEST_NOTIFY_EXTERNAL:
1437		free_irq(ghes->irq, ghes);
1438		break;
1439
1440	case ACPI_HEST_NOTIFY_SCI:
1441	case ACPI_HEST_NOTIFY_GSIV:
1442	case ACPI_HEST_NOTIFY_GPIO:
1443		mutex_lock(&ghes_list_mutex);
1444		list_del_rcu(&ghes->list);
1445		if (list_empty(&ghes_hed))
1446			unregister_acpi_hed_notifier(&ghes_notifier_hed);
1447		mutex_unlock(&ghes_list_mutex);
1448		synchronize_rcu();
1449		break;
1450
1451	case ACPI_HEST_NOTIFY_SEA:
1452		ghes_sea_remove(ghes);
1453		break;
1454	case ACPI_HEST_NOTIFY_NMI:
1455		ghes_nmi_remove(ghes);
1456		break;
1457	case ACPI_HEST_NOTIFY_SOFTWARE_DELEGATED:
1458		rc = apei_sdei_unregister_ghes(ghes);
1459		if (rc)
1460			return rc;
1461		break;
1462	default:
1463		BUG();
1464		break;
1465	}
1466
1467	ghes_fini(ghes);
1468
1469	mutex_lock(&ghes_devs_mutex);
1470	list_del(&ghes->elist);
1471	mutex_unlock(&ghes_devs_mutex);
1472
1473	kfree(ghes);
1474
 
 
1475	return 0;
1476}
1477
1478static struct platform_driver ghes_platform_driver = {
1479	.driver		= {
1480		.name	= "GHES",
1481	},
1482	.probe		= ghes_probe,
1483	.remove		= ghes_remove,
1484};
1485
1486void __init acpi_ghes_init(void)
1487{
1488	int rc;
1489
1490	sdei_init();
1491
1492	if (acpi_disabled)
1493		return;
1494
1495	switch (hest_disable) {
1496	case HEST_NOT_FOUND:
1497		return;
1498	case HEST_DISABLED:
1499		pr_info(GHES_PFX "HEST is not enabled!\n");
1500		return;
1501	default:
1502		break;
1503	}
1504
1505	if (ghes_disable) {
1506		pr_info(GHES_PFX "GHES is not enabled!\n");
1507		return;
1508	}
1509
1510	ghes_nmi_init_cxt();
1511
1512	rc = platform_driver_register(&ghes_platform_driver);
1513	if (rc)
1514		return;
1515
1516	rc = apei_osc_setup();
1517	if (rc == 0 && osc_sb_apei_support_acked)
1518		pr_info(GHES_PFX "APEI firmware first mode is enabled by APEI bit and WHEA _OSC.\n");
1519	else if (rc == 0 && !osc_sb_apei_support_acked)
1520		pr_info(GHES_PFX "APEI firmware first mode is enabled by WHEA _OSC.\n");
1521	else if (rc && osc_sb_apei_support_acked)
1522		pr_info(GHES_PFX "APEI firmware first mode is enabled by APEI bit.\n");
1523	else
1524		pr_info(GHES_PFX "Failed to enable APEI firmware first mode.\n");
1525}
1526
1527/*
1528 * Known x86 systems that prefer GHES error reporting:
1529 */
1530static struct acpi_platform_list plat_list[] = {
1531	{"HPE   ", "Server  ", 0, ACPI_SIG_FADT, all_versions},
1532	{ } /* End */
1533};
1534
1535struct list_head *ghes_get_devices(void)
1536{
1537	int idx = -1;
1538
1539	if (IS_ENABLED(CONFIG_X86)) {
1540		idx = acpi_match_platform_list(plat_list);
1541		if (idx < 0) {
1542			if (!ghes_edac_force_enable)
1543				return NULL;
1544
1545			pr_warn_once("Force-loading ghes_edac on an unsupported platform. You're on your own!\n");
1546		}
1547	}
1548
1549	return &ghes_devs;
1550}
1551EXPORT_SYMBOL_GPL(ghes_get_devices);
1552
1553void ghes_register_report_chain(struct notifier_block *nb)
1554{
1555	atomic_notifier_chain_register(&ghes_report_chain, nb);
1556}
1557EXPORT_SYMBOL_GPL(ghes_register_report_chain);
1558
1559void ghes_unregister_report_chain(struct notifier_block *nb)
1560{
1561	atomic_notifier_chain_unregister(&ghes_report_chain, nb);
1562}
1563EXPORT_SYMBOL_GPL(ghes_unregister_report_chain);