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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);
v6.8
   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 * A platform may describe one error source for the handling of synchronous
 106 * errors (e.g. MCE or SEA), or for handling asynchronous errors (e.g. SCI
 107 * or External Interrupt). On x86, the HEST notifications are always
 108 * asynchronous, so only SEA on ARM is delivered as a synchronous
 109 * notification.
 110 */
 111static inline bool is_hest_sync_notify(struct ghes *ghes)
 112{
 113	u8 notify_type = ghes->generic->notify.type;
 114
 115	return notify_type == ACPI_HEST_NOTIFY_SEA;
 116}
 117
 118/*
 119 * This driver isn't really modular, however for the time being,
 120 * continuing to use module_param is the easiest way to remain
 121 * compatible with existing boot arg use cases.
 122 */
 123bool ghes_disable;
 124module_param_named(disable, ghes_disable, bool, 0);
 125
 126/*
 127 * "ghes.edac_force_enable" forcibly enables ghes_edac and skips the platform
 128 * check.
 129 */
 130static bool ghes_edac_force_enable;
 131module_param_named(edac_force_enable, ghes_edac_force_enable, bool, 0);
 132
 133/*
 134 * All error sources notified with HED (Hardware Error Device) share a
 135 * single notifier callback, so they need to be linked and checked one
 136 * by one. This holds true for NMI too.
 137 *
 138 * RCU is used for these lists, so ghes_list_mutex is only used for
 139 * list changing, not for traversing.
 140 */
 141static LIST_HEAD(ghes_hed);
 142static DEFINE_MUTEX(ghes_list_mutex);
 143
 144/*
 145 * A list of GHES devices which are given to the corresponding EDAC driver
 146 * ghes_edac for further use.
 147 */
 148static LIST_HEAD(ghes_devs);
 149static DEFINE_MUTEX(ghes_devs_mutex);
 150
 151/*
 152 * Because the memory area used to transfer hardware error information
 153 * from BIOS to Linux can be determined only in NMI, IRQ or timer
 154 * handler, but general ioremap can not be used in atomic context, so
 155 * the fixmap is used instead.
 156 *
 157 * This spinlock is used to prevent the fixmap entry from being used
 158 * simultaneously.
 159 */
 160static DEFINE_SPINLOCK(ghes_notify_lock_irq);
 161
 162struct ghes_vendor_record_entry {
 163	struct work_struct work;
 164	int error_severity;
 165	char vendor_record[];
 166};
 167
 168static struct gen_pool *ghes_estatus_pool;
 
 169
 170static struct ghes_estatus_cache __rcu *ghes_estatus_caches[GHES_ESTATUS_CACHES_SIZE];
 171static atomic_t ghes_estatus_cache_alloced;
 172
 173static int ghes_panic_timeout __read_mostly = 30;
 174
 175static void __iomem *ghes_map(u64 pfn, enum fixed_addresses fixmap_idx)
 176{
 177	phys_addr_t paddr;
 178	pgprot_t prot;
 179
 180	paddr = PFN_PHYS(pfn);
 181	prot = arch_apei_get_mem_attribute(paddr);
 182	__set_fixmap(fixmap_idx, paddr, prot);
 183
 184	return (void __iomem *) __fix_to_virt(fixmap_idx);
 185}
 186
 187static void ghes_unmap(void __iomem *vaddr, enum fixed_addresses fixmap_idx)
 188{
 189	int _idx = virt_to_fix((unsigned long)vaddr);
 190
 191	WARN_ON_ONCE(fixmap_idx != _idx);
 192	clear_fixmap(fixmap_idx);
 193}
 194
 195int ghes_estatus_pool_init(unsigned int num_ghes)
 196{
 197	unsigned long addr, len;
 198	int rc;
 199
 200	ghes_estatus_pool = gen_pool_create(GHES_ESTATUS_POOL_MIN_ALLOC_ORDER, -1);
 201	if (!ghes_estatus_pool)
 202		return -ENOMEM;
 203
 204	len = GHES_ESTATUS_CACHE_AVG_SIZE * GHES_ESTATUS_CACHE_ALLOCED_MAX;
 205	len += (num_ghes * GHES_ESOURCE_PREALLOC_MAX_SIZE);
 206
 
 207	addr = (unsigned long)vmalloc(PAGE_ALIGN(len));
 208	if (!addr)
 209		goto err_pool_alloc;
 210
 211	rc = gen_pool_add(ghes_estatus_pool, addr, PAGE_ALIGN(len), -1);
 212	if (rc)
 213		goto err_pool_add;
 214
 215	return 0;
 216
 217err_pool_add:
 218	vfree((void *)addr);
 219
 220err_pool_alloc:
 221	gen_pool_destroy(ghes_estatus_pool);
 222
 223	return -ENOMEM;
 224}
 225
 226/**
 227 * ghes_estatus_pool_region_free - free previously allocated memory
 228 *				   from the ghes_estatus_pool.
 229 * @addr: address of memory to free.
 230 * @size: size of memory to free.
 231 *
 232 * Returns none.
 233 */
 234void ghes_estatus_pool_region_free(unsigned long addr, u32 size)
 235{
 236	gen_pool_free(ghes_estatus_pool, addr, size);
 237}
 238EXPORT_SYMBOL_GPL(ghes_estatus_pool_region_free);
 239
 240static int map_gen_v2(struct ghes *ghes)
 241{
 242	return apei_map_generic_address(&ghes->generic_v2->read_ack_register);
 243}
 244
 245static void unmap_gen_v2(struct ghes *ghes)
 246{
 247	apei_unmap_generic_address(&ghes->generic_v2->read_ack_register);
 248}
 249
 250static void ghes_ack_error(struct acpi_hest_generic_v2 *gv2)
 251{
 252	int rc;
 253	u64 val = 0;
 254
 255	rc = apei_read(&val, &gv2->read_ack_register);
 256	if (rc)
 257		return;
 258
 259	val &= gv2->read_ack_preserve << gv2->read_ack_register.bit_offset;
 260	val |= gv2->read_ack_write    << gv2->read_ack_register.bit_offset;
 261
 262	apei_write(val, &gv2->read_ack_register);
 263}
 264
 265static struct ghes *ghes_new(struct acpi_hest_generic *generic)
 266{
 267	struct ghes *ghes;
 268	unsigned int error_block_length;
 269	int rc;
 270
 271	ghes = kzalloc(sizeof(*ghes), GFP_KERNEL);
 272	if (!ghes)
 273		return ERR_PTR(-ENOMEM);
 274
 275	ghes->generic = generic;
 276	if (is_hest_type_generic_v2(ghes)) {
 277		rc = map_gen_v2(ghes);
 278		if (rc)
 279			goto err_free;
 280	}
 281
 282	rc = apei_map_generic_address(&generic->error_status_address);
 283	if (rc)
 284		goto err_unmap_read_ack_addr;
 285	error_block_length = generic->error_block_length;
 286	if (error_block_length > GHES_ESTATUS_MAX_SIZE) {
 287		pr_warn(FW_WARN GHES_PFX
 288			"Error status block length is too long: %u for "
 289			"generic hardware error source: %d.\n",
 290			error_block_length, generic->header.source_id);
 291		error_block_length = GHES_ESTATUS_MAX_SIZE;
 292	}
 293	ghes->estatus = kmalloc(error_block_length, GFP_KERNEL);
 294	if (!ghes->estatus) {
 295		rc = -ENOMEM;
 296		goto err_unmap_status_addr;
 297	}
 298
 299	return ghes;
 300
 301err_unmap_status_addr:
 302	apei_unmap_generic_address(&generic->error_status_address);
 303err_unmap_read_ack_addr:
 304	if (is_hest_type_generic_v2(ghes))
 305		unmap_gen_v2(ghes);
 306err_free:
 307	kfree(ghes);
 308	return ERR_PTR(rc);
 309}
 310
 311static void ghes_fini(struct ghes *ghes)
 312{
 313	kfree(ghes->estatus);
 314	apei_unmap_generic_address(&ghes->generic->error_status_address);
 315	if (is_hest_type_generic_v2(ghes))
 316		unmap_gen_v2(ghes);
 317}
 318
 319static inline int ghes_severity(int severity)
 320{
 321	switch (severity) {
 322	case CPER_SEV_INFORMATIONAL:
 323		return GHES_SEV_NO;
 324	case CPER_SEV_CORRECTED:
 325		return GHES_SEV_CORRECTED;
 326	case CPER_SEV_RECOVERABLE:
 327		return GHES_SEV_RECOVERABLE;
 328	case CPER_SEV_FATAL:
 329		return GHES_SEV_PANIC;
 330	default:
 331		/* Unknown, go panic */
 332		return GHES_SEV_PANIC;
 333	}
 334}
 335
 336static void ghes_copy_tofrom_phys(void *buffer, u64 paddr, u32 len,
 337				  int from_phys,
 338				  enum fixed_addresses fixmap_idx)
 339{
 340	void __iomem *vaddr;
 341	u64 offset;
 342	u32 trunk;
 343
 344	while (len > 0) {
 345		offset = paddr - (paddr & PAGE_MASK);
 346		vaddr = ghes_map(PHYS_PFN(paddr), fixmap_idx);
 347		trunk = PAGE_SIZE - offset;
 348		trunk = min(trunk, len);
 349		if (from_phys)
 350			memcpy_fromio(buffer, vaddr + offset, trunk);
 351		else
 352			memcpy_toio(vaddr + offset, buffer, trunk);
 353		len -= trunk;
 354		paddr += trunk;
 355		buffer += trunk;
 356		ghes_unmap(vaddr, fixmap_idx);
 357	}
 358}
 359
 360/* Check the top-level record header has an appropriate size. */
 361static int __ghes_check_estatus(struct ghes *ghes,
 362				struct acpi_hest_generic_status *estatus)
 363{
 364	u32 len = cper_estatus_len(estatus);
 365
 366	if (len < sizeof(*estatus)) {
 367		pr_warn_ratelimited(FW_WARN GHES_PFX "Truncated error status block!\n");
 368		return -EIO;
 369	}
 370
 371	if (len > ghes->generic->error_block_length) {
 372		pr_warn_ratelimited(FW_WARN GHES_PFX "Invalid error status block length!\n");
 373		return -EIO;
 374	}
 375
 376	if (cper_estatus_check_header(estatus)) {
 377		pr_warn_ratelimited(FW_WARN GHES_PFX "Invalid CPER header!\n");
 378		return -EIO;
 379	}
 380
 381	return 0;
 382}
 383
 384/* Read the CPER block, returning its address, and header in estatus. */
 385static int __ghes_peek_estatus(struct ghes *ghes,
 386			       struct acpi_hest_generic_status *estatus,
 387			       u64 *buf_paddr, enum fixed_addresses fixmap_idx)
 388{
 389	struct acpi_hest_generic *g = ghes->generic;
 390	int rc;
 391
 392	rc = apei_read(buf_paddr, &g->error_status_address);
 393	if (rc) {
 394		*buf_paddr = 0;
 395		pr_warn_ratelimited(FW_WARN GHES_PFX
 396"Failed to read error status block address for hardware error source: %d.\n",
 397				   g->header.source_id);
 398		return -EIO;
 399	}
 400	if (!*buf_paddr)
 401		return -ENOENT;
 402
 403	ghes_copy_tofrom_phys(estatus, *buf_paddr, sizeof(*estatus), 1,
 404			      fixmap_idx);
 405	if (!estatus->block_status) {
 406		*buf_paddr = 0;
 407		return -ENOENT;
 408	}
 409
 410	return 0;
 411}
 412
 413static int __ghes_read_estatus(struct acpi_hest_generic_status *estatus,
 414			       u64 buf_paddr, enum fixed_addresses fixmap_idx,
 415			       size_t buf_len)
 416{
 417	ghes_copy_tofrom_phys(estatus, buf_paddr, buf_len, 1, fixmap_idx);
 418	if (cper_estatus_check(estatus)) {
 419		pr_warn_ratelimited(FW_WARN GHES_PFX
 420				    "Failed to read error status block!\n");
 421		return -EIO;
 422	}
 423
 424	return 0;
 425}
 426
 427static int ghes_read_estatus(struct ghes *ghes,
 428			     struct acpi_hest_generic_status *estatus,
 429			     u64 *buf_paddr, enum fixed_addresses fixmap_idx)
 430{
 431	int rc;
 432
 433	rc = __ghes_peek_estatus(ghes, estatus, buf_paddr, fixmap_idx);
 434	if (rc)
 435		return rc;
 436
 437	rc = __ghes_check_estatus(ghes, estatus);
 438	if (rc)
 439		return rc;
 440
 441	return __ghes_read_estatus(estatus, *buf_paddr, fixmap_idx,
 442				   cper_estatus_len(estatus));
 443}
 444
 445static void ghes_clear_estatus(struct ghes *ghes,
 446			       struct acpi_hest_generic_status *estatus,
 447			       u64 buf_paddr, enum fixed_addresses fixmap_idx)
 448{
 449	estatus->block_status = 0;
 450
 451	if (!buf_paddr)
 452		return;
 453
 454	ghes_copy_tofrom_phys(estatus, buf_paddr,
 455			      sizeof(estatus->block_status), 0,
 456			      fixmap_idx);
 457
 458	/*
 459	 * GHESv2 type HEST entries introduce support for error acknowledgment,
 460	 * so only acknowledge the error if this support is present.
 461	 */
 462	if (is_hest_type_generic_v2(ghes))
 463		ghes_ack_error(ghes->generic_v2);
 464}
 465
 466/*
 467 * Called as task_work before returning to user-space.
 468 * Ensure any queued work has been done before we return to the context that
 469 * triggered the notification.
 470 */
 471static void ghes_kick_task_work(struct callback_head *head)
 472{
 473	struct acpi_hest_generic_status *estatus;
 474	struct ghes_estatus_node *estatus_node;
 475	u32 node_len;
 476
 477	estatus_node = container_of(head, struct ghes_estatus_node, task_work);
 478	if (IS_ENABLED(CONFIG_ACPI_APEI_MEMORY_FAILURE))
 479		memory_failure_queue_kick(estatus_node->task_work_cpu);
 480
 481	estatus = GHES_ESTATUS_FROM_NODE(estatus_node);
 482	node_len = GHES_ESTATUS_NODE_LEN(cper_estatus_len(estatus));
 483	gen_pool_free(ghes_estatus_pool, (unsigned long)estatus_node, node_len);
 484}
 485
 486static bool ghes_do_memory_failure(u64 physical_addr, int flags)
 
 487{
 488	unsigned long pfn;
 
 
 
 489
 490	if (!IS_ENABLED(CONFIG_ACPI_APEI_MEMORY_FAILURE))
 491		return false;
 492
 493	pfn = PHYS_PFN(physical_addr);
 494	if (!pfn_valid(pfn) && !arch_is_platform_page(physical_addr)) {
 
 
 
 495		pr_warn_ratelimited(FW_WARN GHES_PFX
 496		"Invalid address in generic error data: %#llx\n",
 497		physical_addr);
 498		return false;
 499	}
 500
 501	memory_failure_queue(pfn, flags);
 502	return true;
 503}
 504
 505static bool ghes_handle_memory_failure(struct acpi_hest_generic_data *gdata,
 506				       int sev, bool sync)
 507{
 508	int flags = -1;
 509	int sec_sev = ghes_severity(gdata->error_severity);
 510	struct cper_sec_mem_err *mem_err = acpi_hest_get_payload(gdata);
 511
 512	if (!(mem_err->validation_bits & CPER_MEM_VALID_PA))
 513		return false;
 514
 515	/* iff following two events can be handled properly by now */
 516	if (sec_sev == GHES_SEV_CORRECTED &&
 517	    (gdata->flags & CPER_SEC_ERROR_THRESHOLD_EXCEEDED))
 518		flags = MF_SOFT_OFFLINE;
 519	if (sev == GHES_SEV_RECOVERABLE && sec_sev == GHES_SEV_RECOVERABLE)
 520		flags = sync ? MF_ACTION_REQUIRED : 0;
 521
 522	if (flags != -1)
 523		return ghes_do_memory_failure(mem_err->physical_addr, flags);
 
 
 524
 525	return false;
 526}
 527
 528static bool ghes_handle_arm_hw_error(struct acpi_hest_generic_data *gdata,
 529				       int sev, bool sync)
 530{
 531	struct cper_sec_proc_arm *err = acpi_hest_get_payload(gdata);
 532	int flags = sync ? MF_ACTION_REQUIRED : 0;
 533	bool queued = false;
 534	int sec_sev, i;
 535	char *p;
 536
 537	log_arm_hw_error(err);
 538
 539	sec_sev = ghes_severity(gdata->error_severity);
 540	if (sev != GHES_SEV_RECOVERABLE || sec_sev != GHES_SEV_RECOVERABLE)
 541		return false;
 542
 543	p = (char *)(err + 1);
 544	for (i = 0; i < err->err_info_num; i++) {
 545		struct cper_arm_err_info *err_info = (struct cper_arm_err_info *)p;
 546		bool is_cache = (err_info->type == CPER_ARM_CACHE_ERROR);
 547		bool has_pa = (err_info->validation_bits & CPER_ARM_INFO_VALID_PHYSICAL_ADDR);
 548		const char *error_type = "unknown error";
 549
 550		/*
 551		 * The field (err_info->error_info & BIT(26)) is fixed to set to
 552		 * 1 in some old firmware of HiSilicon Kunpeng920. We assume that
 553		 * firmware won't mix corrected errors in an uncorrected section,
 554		 * and don't filter out 'corrected' error here.
 555		 */
 556		if (is_cache && has_pa) {
 557			queued = ghes_do_memory_failure(err_info->physical_fault_addr, flags);
 558			p += err_info->length;
 559			continue;
 560		}
 561
 562		if (err_info->type < ARRAY_SIZE(cper_proc_error_type_strs))
 563			error_type = cper_proc_error_type_strs[err_info->type];
 564
 565		pr_warn_ratelimited(FW_WARN GHES_PFX
 566				    "Unhandled processor error type: %s\n",
 567				    error_type);
 568		p += err_info->length;
 569	}
 570
 571	return queued;
 572}
 573
 574/*
 575 * PCIe AER errors need to be sent to the AER driver for reporting and
 576 * recovery. The GHES severities map to the following AER severities and
 577 * require the following handling:
 578 *
 579 * GHES_SEV_CORRECTABLE -> AER_CORRECTABLE
 580 *     These need to be reported by the AER driver but no recovery is
 581 *     necessary.
 582 * GHES_SEV_RECOVERABLE -> AER_NONFATAL
 583 * GHES_SEV_RECOVERABLE && CPER_SEC_RESET -> AER_FATAL
 584 *     These both need to be reported and recovered from by the AER driver.
 585 * GHES_SEV_PANIC does not make it to this handling since the kernel must
 586 *     panic.
 587 */
 588static void ghes_handle_aer(struct acpi_hest_generic_data *gdata)
 589{
 590#ifdef CONFIG_ACPI_APEI_PCIEAER
 591	struct cper_sec_pcie *pcie_err = acpi_hest_get_payload(gdata);
 592
 593	if (pcie_err->validation_bits & CPER_PCIE_VALID_DEVICE_ID &&
 594	    pcie_err->validation_bits & CPER_PCIE_VALID_AER_INFO) {
 595		unsigned int devfn;
 596		int aer_severity;
 597		u8 *aer_info;
 598
 599		devfn = PCI_DEVFN(pcie_err->device_id.device,
 600				  pcie_err->device_id.function);
 601		aer_severity = cper_severity_to_aer(gdata->error_severity);
 602
 603		/*
 604		 * If firmware reset the component to contain
 605		 * the error, we must reinitialize it before
 606		 * use, so treat it as a fatal AER error.
 607		 */
 608		if (gdata->flags & CPER_SEC_RESET)
 609			aer_severity = AER_FATAL;
 610
 611		aer_info = (void *)gen_pool_alloc(ghes_estatus_pool,
 612						  sizeof(struct aer_capability_regs));
 613		if (!aer_info)
 614			return;
 615		memcpy(aer_info, pcie_err->aer_info, sizeof(struct aer_capability_regs));
 616
 617		aer_recover_queue(pcie_err->device_id.segment,
 618				  pcie_err->device_id.bus,
 619				  devfn, aer_severity,
 620				  (struct aer_capability_regs *)
 621				  aer_info);
 622	}
 623#endif
 624}
 625
 626static BLOCKING_NOTIFIER_HEAD(vendor_record_notify_list);
 627
 628int ghes_register_vendor_record_notifier(struct notifier_block *nb)
 629{
 630	return blocking_notifier_chain_register(&vendor_record_notify_list, nb);
 631}
 632EXPORT_SYMBOL_GPL(ghes_register_vendor_record_notifier);
 633
 634void ghes_unregister_vendor_record_notifier(struct notifier_block *nb)
 635{
 636	blocking_notifier_chain_unregister(&vendor_record_notify_list, nb);
 637}
 638EXPORT_SYMBOL_GPL(ghes_unregister_vendor_record_notifier);
 639
 640static void ghes_vendor_record_work_func(struct work_struct *work)
 641{
 642	struct ghes_vendor_record_entry *entry;
 643	struct acpi_hest_generic_data *gdata;
 644	u32 len;
 645
 646	entry = container_of(work, struct ghes_vendor_record_entry, work);
 647	gdata = GHES_GDATA_FROM_VENDOR_ENTRY(entry);
 648
 649	blocking_notifier_call_chain(&vendor_record_notify_list,
 650				     entry->error_severity, gdata);
 651
 652	len = GHES_VENDOR_ENTRY_LEN(acpi_hest_get_record_size(gdata));
 653	gen_pool_free(ghes_estatus_pool, (unsigned long)entry, len);
 654}
 655
 656static void ghes_defer_non_standard_event(struct acpi_hest_generic_data *gdata,
 657					  int sev)
 658{
 659	struct acpi_hest_generic_data *copied_gdata;
 660	struct ghes_vendor_record_entry *entry;
 661	u32 len;
 662
 663	len = GHES_VENDOR_ENTRY_LEN(acpi_hest_get_record_size(gdata));
 664	entry = (void *)gen_pool_alloc(ghes_estatus_pool, len);
 665	if (!entry)
 666		return;
 667
 668	copied_gdata = GHES_GDATA_FROM_VENDOR_ENTRY(entry);
 669	memcpy(copied_gdata, gdata, acpi_hest_get_record_size(gdata));
 670	entry->error_severity = sev;
 671
 672	INIT_WORK(&entry->work, ghes_vendor_record_work_func);
 673	schedule_work(&entry->work);
 674}
 675
 676static bool ghes_do_proc(struct ghes *ghes,
 677			 const struct acpi_hest_generic_status *estatus)
 678{
 679	int sev, sec_sev;
 680	struct acpi_hest_generic_data *gdata;
 681	guid_t *sec_type;
 682	const guid_t *fru_id = &guid_null;
 683	char *fru_text = "";
 684	bool queued = false;
 685	bool sync = is_hest_sync_notify(ghes);
 686
 687	sev = ghes_severity(estatus->error_severity);
 688	apei_estatus_for_each_section(estatus, gdata) {
 689		sec_type = (guid_t *)gdata->section_type;
 690		sec_sev = ghes_severity(gdata->error_severity);
 691		if (gdata->validation_bits & CPER_SEC_VALID_FRU_ID)
 692			fru_id = (guid_t *)gdata->fru_id;
 693
 694		if (gdata->validation_bits & CPER_SEC_VALID_FRU_TEXT)
 695			fru_text = gdata->fru_text;
 696
 697		if (guid_equal(sec_type, &CPER_SEC_PLATFORM_MEM)) {
 698			struct cper_sec_mem_err *mem_err = acpi_hest_get_payload(gdata);
 699
 700			atomic_notifier_call_chain(&ghes_report_chain, sev, mem_err);
 701
 702			arch_apei_report_mem_error(sev, mem_err);
 703			queued = ghes_handle_memory_failure(gdata, sev, sync);
 704		}
 705		else if (guid_equal(sec_type, &CPER_SEC_PCIE)) {
 706			ghes_handle_aer(gdata);
 707		}
 708		else if (guid_equal(sec_type, &CPER_SEC_PROC_ARM)) {
 709			queued = ghes_handle_arm_hw_error(gdata, sev, sync);
 
 
 710		} else {
 711			void *err = acpi_hest_get_payload(gdata);
 712
 713			ghes_defer_non_standard_event(gdata, sev);
 714			log_non_standard_event(sec_type, fru_id, fru_text,
 715					       sec_sev, err,
 716					       gdata->error_data_length);
 717		}
 718	}
 719
 720	return queued;
 721}
 722
 723static void __ghes_print_estatus(const char *pfx,
 724				 const struct acpi_hest_generic *generic,
 725				 const struct acpi_hest_generic_status *estatus)
 726{
 727	static atomic_t seqno;
 728	unsigned int curr_seqno;
 729	char pfx_seq[64];
 730
 731	if (pfx == NULL) {
 732		if (ghes_severity(estatus->error_severity) <=
 733		    GHES_SEV_CORRECTED)
 734			pfx = KERN_WARNING;
 735		else
 736			pfx = KERN_ERR;
 737	}
 738	curr_seqno = atomic_inc_return(&seqno);
 739	snprintf(pfx_seq, sizeof(pfx_seq), "%s{%u}" HW_ERR, pfx, curr_seqno);
 740	printk("%s""Hardware error from APEI Generic Hardware Error Source: %d\n",
 741	       pfx_seq, generic->header.source_id);
 742	cper_estatus_print(pfx_seq, estatus);
 743}
 744
 745static int ghes_print_estatus(const char *pfx,
 746			      const struct acpi_hest_generic *generic,
 747			      const struct acpi_hest_generic_status *estatus)
 748{
 749	/* Not more than 2 messages every 5 seconds */
 750	static DEFINE_RATELIMIT_STATE(ratelimit_corrected, 5*HZ, 2);
 751	static DEFINE_RATELIMIT_STATE(ratelimit_uncorrected, 5*HZ, 2);
 752	struct ratelimit_state *ratelimit;
 753
 754	if (ghes_severity(estatus->error_severity) <= GHES_SEV_CORRECTED)
 755		ratelimit = &ratelimit_corrected;
 756	else
 757		ratelimit = &ratelimit_uncorrected;
 758	if (__ratelimit(ratelimit)) {
 759		__ghes_print_estatus(pfx, generic, estatus);
 760		return 1;
 761	}
 762	return 0;
 763}
 764
 765/*
 766 * GHES error status reporting throttle, to report more kinds of
 767 * errors, instead of just most frequently occurred errors.
 768 */
 769static int ghes_estatus_cached(struct acpi_hest_generic_status *estatus)
 770{
 771	u32 len;
 772	int i, cached = 0;
 773	unsigned long long now;
 774	struct ghes_estatus_cache *cache;
 775	struct acpi_hest_generic_status *cache_estatus;
 776
 777	len = cper_estatus_len(estatus);
 778	rcu_read_lock();
 779	for (i = 0; i < GHES_ESTATUS_CACHES_SIZE; i++) {
 780		cache = rcu_dereference(ghes_estatus_caches[i]);
 781		if (cache == NULL)
 782			continue;
 783		if (len != cache->estatus_len)
 784			continue;
 785		cache_estatus = GHES_ESTATUS_FROM_CACHE(cache);
 786		if (memcmp(estatus, cache_estatus, len))
 787			continue;
 788		atomic_inc(&cache->count);
 789		now = sched_clock();
 790		if (now - cache->time_in < GHES_ESTATUS_IN_CACHE_MAX_NSEC)
 791			cached = 1;
 792		break;
 793	}
 794	rcu_read_unlock();
 795	return cached;
 796}
 797
 798static struct ghes_estatus_cache *ghes_estatus_cache_alloc(
 799	struct acpi_hest_generic *generic,
 800	struct acpi_hest_generic_status *estatus)
 801{
 802	int alloced;
 803	u32 len, cache_len;
 804	struct ghes_estatus_cache *cache;
 805	struct acpi_hest_generic_status *cache_estatus;
 806
 807	alloced = atomic_add_return(1, &ghes_estatus_cache_alloced);
 808	if (alloced > GHES_ESTATUS_CACHE_ALLOCED_MAX) {
 809		atomic_dec(&ghes_estatus_cache_alloced);
 810		return NULL;
 811	}
 812	len = cper_estatus_len(estatus);
 813	cache_len = GHES_ESTATUS_CACHE_LEN(len);
 814	cache = (void *)gen_pool_alloc(ghes_estatus_pool, cache_len);
 815	if (!cache) {
 816		atomic_dec(&ghes_estatus_cache_alloced);
 817		return NULL;
 818	}
 819	cache_estatus = GHES_ESTATUS_FROM_CACHE(cache);
 820	memcpy(cache_estatus, estatus, len);
 821	cache->estatus_len = len;
 822	atomic_set(&cache->count, 0);
 823	cache->generic = generic;
 824	cache->time_in = sched_clock();
 825	return cache;
 826}
 827
 828static void ghes_estatus_cache_rcu_free(struct rcu_head *head)
 829{
 830	struct ghes_estatus_cache *cache;
 831	u32 len;
 832
 833	cache = container_of(head, struct ghes_estatus_cache, rcu);
 834	len = cper_estatus_len(GHES_ESTATUS_FROM_CACHE(cache));
 835	len = GHES_ESTATUS_CACHE_LEN(len);
 836	gen_pool_free(ghes_estatus_pool, (unsigned long)cache, len);
 837	atomic_dec(&ghes_estatus_cache_alloced);
 838}
 839
 840static void
 841ghes_estatus_cache_add(struct acpi_hest_generic *generic,
 842		       struct acpi_hest_generic_status *estatus)
 
 
 
 
 
 
 
 
 843{
 
 844	unsigned long long now, duration, period, max_period = 0;
 845	struct ghes_estatus_cache *cache, *new_cache;
 846	struct ghes_estatus_cache __rcu *victim;
 847	int i, slot = -1, count;
 848
 849	new_cache = ghes_estatus_cache_alloc(generic, estatus);
 850	if (!new_cache)
 851		return;
 852
 853	rcu_read_lock();
 854	now = sched_clock();
 855	for (i = 0; i < GHES_ESTATUS_CACHES_SIZE; i++) {
 856		cache = rcu_dereference(ghes_estatus_caches[i]);
 857		if (cache == NULL) {
 858			slot = i;
 
 859			break;
 860		}
 861		duration = now - cache->time_in;
 862		if (duration >= GHES_ESTATUS_IN_CACHE_MAX_NSEC) {
 863			slot = i;
 
 864			break;
 865		}
 866		count = atomic_read(&cache->count);
 867		period = duration;
 868		do_div(period, (count + 1));
 869		if (period > max_period) {
 870			max_period = period;
 871			slot = i;
 
 872		}
 873	}
 
 
 
 
 
 
 
 
 874	rcu_read_unlock();
 875
 876	if (slot != -1) {
 877		/*
 878		 * Use release semantics to ensure that ghes_estatus_cached()
 879		 * running on another CPU will see the updated cache fields if
 880		 * it can see the new value of the pointer.
 881		 */
 882		victim = xchg_release(&ghes_estatus_caches[slot],
 883				      RCU_INITIALIZER(new_cache));
 884
 885		/*
 886		 * At this point, victim may point to a cached item different
 887		 * from the one based on which we selected the slot. Instead of
 888		 * going to the loop again to pick another slot, let's just
 889		 * drop the other item anyway: this may cause a false cache
 890		 * miss later on, but that won't cause any problems.
 891		 */
 892		if (victim)
 893			call_rcu(&unrcu_pointer(victim)->rcu,
 894				 ghes_estatus_cache_rcu_free);
 895	}
 896}
 897
 898static void __ghes_panic(struct ghes *ghes,
 899			 struct acpi_hest_generic_status *estatus,
 900			 u64 buf_paddr, enum fixed_addresses fixmap_idx)
 901{
 902	__ghes_print_estatus(KERN_EMERG, ghes->generic, estatus);
 903
 904	ghes_clear_estatus(ghes, estatus, buf_paddr, fixmap_idx);
 905
 906	/* reboot to log the error! */
 907	if (!panic_timeout)
 908		panic_timeout = ghes_panic_timeout;
 909	panic("Fatal hardware error!");
 910}
 911
 912static int ghes_proc(struct ghes *ghes)
 913{
 914	struct acpi_hest_generic_status *estatus = ghes->estatus;
 915	u64 buf_paddr;
 916	int rc;
 917
 918	rc = ghes_read_estatus(ghes, estatus, &buf_paddr, FIX_APEI_GHES_IRQ);
 919	if (rc)
 920		goto out;
 921
 922	if (ghes_severity(estatus->error_severity) >= GHES_SEV_PANIC)
 923		__ghes_panic(ghes, estatus, buf_paddr, FIX_APEI_GHES_IRQ);
 924
 925	if (!ghes_estatus_cached(estatus)) {
 926		if (ghes_print_estatus(NULL, ghes->generic, estatus))
 927			ghes_estatus_cache_add(ghes->generic, estatus);
 928	}
 929	ghes_do_proc(ghes, estatus);
 930
 931out:
 932	ghes_clear_estatus(ghes, estatus, buf_paddr, FIX_APEI_GHES_IRQ);
 933
 934	return rc;
 935}
 936
 937static void ghes_add_timer(struct ghes *ghes)
 938{
 939	struct acpi_hest_generic *g = ghes->generic;
 940	unsigned long expire;
 941
 942	if (!g->notify.poll_interval) {
 943		pr_warn(FW_WARN GHES_PFX "Poll interval is 0 for generic hardware error source: %d, disabled.\n",
 944			g->header.source_id);
 945		return;
 946	}
 947	expire = jiffies + msecs_to_jiffies(g->notify.poll_interval);
 948	ghes->timer.expires = round_jiffies_relative(expire);
 949	add_timer(&ghes->timer);
 950}
 951
 952static void ghes_poll_func(struct timer_list *t)
 953{
 954	struct ghes *ghes = from_timer(ghes, t, timer);
 955	unsigned long flags;
 956
 957	spin_lock_irqsave(&ghes_notify_lock_irq, flags);
 958	ghes_proc(ghes);
 959	spin_unlock_irqrestore(&ghes_notify_lock_irq, flags);
 960	if (!(ghes->flags & GHES_EXITING))
 961		ghes_add_timer(ghes);
 962}
 963
 964static irqreturn_t ghes_irq_func(int irq, void *data)
 965{
 966	struct ghes *ghes = data;
 967	unsigned long flags;
 968	int rc;
 969
 970	spin_lock_irqsave(&ghes_notify_lock_irq, flags);
 971	rc = ghes_proc(ghes);
 972	spin_unlock_irqrestore(&ghes_notify_lock_irq, flags);
 973	if (rc)
 974		return IRQ_NONE;
 975
 976	return IRQ_HANDLED;
 977}
 978
 979static int ghes_notify_hed(struct notifier_block *this, unsigned long event,
 980			   void *data)
 981{
 982	struct ghes *ghes;
 983	unsigned long flags;
 984	int ret = NOTIFY_DONE;
 985
 986	spin_lock_irqsave(&ghes_notify_lock_irq, flags);
 987	rcu_read_lock();
 988	list_for_each_entry_rcu(ghes, &ghes_hed, list) {
 989		if (!ghes_proc(ghes))
 990			ret = NOTIFY_OK;
 991	}
 992	rcu_read_unlock();
 993	spin_unlock_irqrestore(&ghes_notify_lock_irq, flags);
 994
 995	return ret;
 996}
 997
 998static struct notifier_block ghes_notifier_hed = {
 999	.notifier_call = ghes_notify_hed,
1000};
1001
1002/*
1003 * Handlers for CPER records may not be NMI safe. For example,
1004 * memory_failure_queue() takes spinlocks and calls schedule_work_on().
1005 * In any NMI-like handler, memory from ghes_estatus_pool is used to save
1006 * estatus, and added to the ghes_estatus_llist. irq_work_queue() causes
1007 * ghes_proc_in_irq() to run in IRQ context where each estatus in
1008 * ghes_estatus_llist is processed.
1009 *
1010 * Memory from the ghes_estatus_pool is also used with the ghes_estatus_cache
1011 * to suppress frequent messages.
1012 */
1013static struct llist_head ghes_estatus_llist;
1014static struct irq_work ghes_proc_irq_work;
1015
1016static void ghes_proc_in_irq(struct irq_work *irq_work)
1017{
1018	struct llist_node *llnode, *next;
1019	struct ghes_estatus_node *estatus_node;
1020	struct acpi_hest_generic *generic;
1021	struct acpi_hest_generic_status *estatus;
1022	bool task_work_pending;
1023	u32 len, node_len;
1024	int ret;
1025
1026	llnode = llist_del_all(&ghes_estatus_llist);
1027	/*
1028	 * Because the time order of estatus in list is reversed,
1029	 * revert it back to proper order.
1030	 */
1031	llnode = llist_reverse_order(llnode);
1032	while (llnode) {
1033		next = llnode->next;
1034		estatus_node = llist_entry(llnode, struct ghes_estatus_node,
1035					   llnode);
1036		estatus = GHES_ESTATUS_FROM_NODE(estatus_node);
1037		len = cper_estatus_len(estatus);
1038		node_len = GHES_ESTATUS_NODE_LEN(len);
1039		task_work_pending = ghes_do_proc(estatus_node->ghes, estatus);
1040		if (!ghes_estatus_cached(estatus)) {
1041			generic = estatus_node->generic;
1042			if (ghes_print_estatus(NULL, generic, estatus))
1043				ghes_estatus_cache_add(generic, estatus);
1044		}
1045
1046		if (task_work_pending && current->mm) {
1047			estatus_node->task_work.func = ghes_kick_task_work;
1048			estatus_node->task_work_cpu = smp_processor_id();
1049			ret = task_work_add(current, &estatus_node->task_work,
1050					    TWA_RESUME);
1051			if (ret)
1052				estatus_node->task_work.func = NULL;
1053		}
1054
1055		if (!estatus_node->task_work.func)
1056			gen_pool_free(ghes_estatus_pool,
1057				      (unsigned long)estatus_node, node_len);
1058
1059		llnode = next;
1060	}
1061}
1062
1063static void ghes_print_queued_estatus(void)
1064{
1065	struct llist_node *llnode;
1066	struct ghes_estatus_node *estatus_node;
1067	struct acpi_hest_generic *generic;
1068	struct acpi_hest_generic_status *estatus;
1069
1070	llnode = llist_del_all(&ghes_estatus_llist);
1071	/*
1072	 * Because the time order of estatus in list is reversed,
1073	 * revert it back to proper order.
1074	 */
1075	llnode = llist_reverse_order(llnode);
1076	while (llnode) {
1077		estatus_node = llist_entry(llnode, struct ghes_estatus_node,
1078					   llnode);
1079		estatus = GHES_ESTATUS_FROM_NODE(estatus_node);
1080		generic = estatus_node->generic;
1081		ghes_print_estatus(NULL, generic, estatus);
1082		llnode = llnode->next;
1083	}
1084}
1085
1086static int ghes_in_nmi_queue_one_entry(struct ghes *ghes,
1087				       enum fixed_addresses fixmap_idx)
1088{
1089	struct acpi_hest_generic_status *estatus, tmp_header;
1090	struct ghes_estatus_node *estatus_node;
1091	u32 len, node_len;
1092	u64 buf_paddr;
1093	int sev, rc;
1094
1095	if (!IS_ENABLED(CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG))
1096		return -EOPNOTSUPP;
1097
1098	rc = __ghes_peek_estatus(ghes, &tmp_header, &buf_paddr, fixmap_idx);
1099	if (rc) {
1100		ghes_clear_estatus(ghes, &tmp_header, buf_paddr, fixmap_idx);
1101		return rc;
1102	}
1103
1104	rc = __ghes_check_estatus(ghes, &tmp_header);
1105	if (rc) {
1106		ghes_clear_estatus(ghes, &tmp_header, buf_paddr, fixmap_idx);
1107		return rc;
1108	}
1109
1110	len = cper_estatus_len(&tmp_header);
1111	node_len = GHES_ESTATUS_NODE_LEN(len);
1112	estatus_node = (void *)gen_pool_alloc(ghes_estatus_pool, node_len);
1113	if (!estatus_node)
1114		return -ENOMEM;
1115
1116	estatus_node->ghes = ghes;
1117	estatus_node->generic = ghes->generic;
1118	estatus_node->task_work.func = NULL;
1119	estatus = GHES_ESTATUS_FROM_NODE(estatus_node);
1120
1121	if (__ghes_read_estatus(estatus, buf_paddr, fixmap_idx, len)) {
1122		ghes_clear_estatus(ghes, estatus, buf_paddr, fixmap_idx);
1123		rc = -ENOENT;
1124		goto no_work;
1125	}
1126
1127	sev = ghes_severity(estatus->error_severity);
1128	if (sev >= GHES_SEV_PANIC) {
1129		ghes_print_queued_estatus();
1130		__ghes_panic(ghes, estatus, buf_paddr, fixmap_idx);
1131	}
1132
1133	ghes_clear_estatus(ghes, &tmp_header, buf_paddr, fixmap_idx);
1134
1135	/* This error has been reported before, don't process it again. */
1136	if (ghes_estatus_cached(estatus))
1137		goto no_work;
1138
1139	llist_add(&estatus_node->llnode, &ghes_estatus_llist);
1140
1141	return rc;
1142
1143no_work:
1144	gen_pool_free(ghes_estatus_pool, (unsigned long)estatus_node,
1145		      node_len);
1146
1147	return rc;
1148}
1149
1150static int ghes_in_nmi_spool_from_list(struct list_head *rcu_list,
1151				       enum fixed_addresses fixmap_idx)
1152{
1153	int ret = -ENOENT;
1154	struct ghes *ghes;
1155
1156	rcu_read_lock();
1157	list_for_each_entry_rcu(ghes, rcu_list, list) {
1158		if (!ghes_in_nmi_queue_one_entry(ghes, fixmap_idx))
1159			ret = 0;
1160	}
1161	rcu_read_unlock();
1162
1163	if (IS_ENABLED(CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG) && !ret)
1164		irq_work_queue(&ghes_proc_irq_work);
1165
1166	return ret;
1167}
1168
1169#ifdef CONFIG_ACPI_APEI_SEA
1170static LIST_HEAD(ghes_sea);
1171
1172/*
1173 * Return 0 only if one of the SEA error sources successfully reported an error
1174 * record sent from the firmware.
1175 */
1176int ghes_notify_sea(void)
1177{
1178	static DEFINE_RAW_SPINLOCK(ghes_notify_lock_sea);
1179	int rv;
1180
1181	raw_spin_lock(&ghes_notify_lock_sea);
1182	rv = ghes_in_nmi_spool_from_list(&ghes_sea, FIX_APEI_GHES_SEA);
1183	raw_spin_unlock(&ghes_notify_lock_sea);
1184
1185	return rv;
1186}
1187
1188static void ghes_sea_add(struct ghes *ghes)
1189{
1190	mutex_lock(&ghes_list_mutex);
1191	list_add_rcu(&ghes->list, &ghes_sea);
1192	mutex_unlock(&ghes_list_mutex);
1193}
1194
1195static void ghes_sea_remove(struct ghes *ghes)
1196{
1197	mutex_lock(&ghes_list_mutex);
1198	list_del_rcu(&ghes->list);
1199	mutex_unlock(&ghes_list_mutex);
1200	synchronize_rcu();
1201}
1202#else /* CONFIG_ACPI_APEI_SEA */
1203static inline void ghes_sea_add(struct ghes *ghes) { }
1204static inline void ghes_sea_remove(struct ghes *ghes) { }
1205#endif /* CONFIG_ACPI_APEI_SEA */
1206
1207#ifdef CONFIG_HAVE_ACPI_APEI_NMI
1208/*
1209 * NMI may be triggered on any CPU, so ghes_in_nmi is used for
1210 * having only one concurrent reader.
1211 */
1212static atomic_t ghes_in_nmi = ATOMIC_INIT(0);
1213
1214static LIST_HEAD(ghes_nmi);
1215
1216static int ghes_notify_nmi(unsigned int cmd, struct pt_regs *regs)
1217{
1218	static DEFINE_RAW_SPINLOCK(ghes_notify_lock_nmi);
1219	int ret = NMI_DONE;
1220
1221	if (!atomic_add_unless(&ghes_in_nmi, 1, 1))
1222		return ret;
1223
1224	raw_spin_lock(&ghes_notify_lock_nmi);
1225	if (!ghes_in_nmi_spool_from_list(&ghes_nmi, FIX_APEI_GHES_NMI))
1226		ret = NMI_HANDLED;
1227	raw_spin_unlock(&ghes_notify_lock_nmi);
1228
1229	atomic_dec(&ghes_in_nmi);
1230	return ret;
1231}
1232
1233static void ghes_nmi_add(struct ghes *ghes)
1234{
1235	mutex_lock(&ghes_list_mutex);
1236	if (list_empty(&ghes_nmi))
1237		register_nmi_handler(NMI_LOCAL, ghes_notify_nmi, 0, "ghes");
1238	list_add_rcu(&ghes->list, &ghes_nmi);
1239	mutex_unlock(&ghes_list_mutex);
1240}
1241
1242static void ghes_nmi_remove(struct ghes *ghes)
1243{
1244	mutex_lock(&ghes_list_mutex);
1245	list_del_rcu(&ghes->list);
1246	if (list_empty(&ghes_nmi))
1247		unregister_nmi_handler(NMI_LOCAL, "ghes");
1248	mutex_unlock(&ghes_list_mutex);
1249	/*
1250	 * To synchronize with NMI handler, ghes can only be
1251	 * freed after NMI handler finishes.
1252	 */
1253	synchronize_rcu();
1254}
1255#else /* CONFIG_HAVE_ACPI_APEI_NMI */
1256static inline void ghes_nmi_add(struct ghes *ghes) { }
1257static inline void ghes_nmi_remove(struct ghes *ghes) { }
1258#endif /* CONFIG_HAVE_ACPI_APEI_NMI */
1259
1260static void ghes_nmi_init_cxt(void)
1261{
1262	init_irq_work(&ghes_proc_irq_work, ghes_proc_in_irq);
1263}
1264
1265static int __ghes_sdei_callback(struct ghes *ghes,
1266				enum fixed_addresses fixmap_idx)
1267{
1268	if (!ghes_in_nmi_queue_one_entry(ghes, fixmap_idx)) {
1269		irq_work_queue(&ghes_proc_irq_work);
1270
1271		return 0;
1272	}
1273
1274	return -ENOENT;
1275}
1276
1277static int ghes_sdei_normal_callback(u32 event_num, struct pt_regs *regs,
1278				      void *arg)
1279{
1280	static DEFINE_RAW_SPINLOCK(ghes_notify_lock_sdei_normal);
1281	struct ghes *ghes = arg;
1282	int err;
1283
1284	raw_spin_lock(&ghes_notify_lock_sdei_normal);
1285	err = __ghes_sdei_callback(ghes, FIX_APEI_GHES_SDEI_NORMAL);
1286	raw_spin_unlock(&ghes_notify_lock_sdei_normal);
1287
1288	return err;
1289}
1290
1291static int ghes_sdei_critical_callback(u32 event_num, struct pt_regs *regs,
1292				       void *arg)
1293{
1294	static DEFINE_RAW_SPINLOCK(ghes_notify_lock_sdei_critical);
1295	struct ghes *ghes = arg;
1296	int err;
1297
1298	raw_spin_lock(&ghes_notify_lock_sdei_critical);
1299	err = __ghes_sdei_callback(ghes, FIX_APEI_GHES_SDEI_CRITICAL);
1300	raw_spin_unlock(&ghes_notify_lock_sdei_critical);
1301
1302	return err;
1303}
1304
1305static int apei_sdei_register_ghes(struct ghes *ghes)
1306{
1307	if (!IS_ENABLED(CONFIG_ARM_SDE_INTERFACE))
1308		return -EOPNOTSUPP;
1309
1310	return sdei_register_ghes(ghes, ghes_sdei_normal_callback,
1311				 ghes_sdei_critical_callback);
1312}
1313
1314static int apei_sdei_unregister_ghes(struct ghes *ghes)
1315{
1316	if (!IS_ENABLED(CONFIG_ARM_SDE_INTERFACE))
1317		return -EOPNOTSUPP;
1318
1319	return sdei_unregister_ghes(ghes);
1320}
1321
1322static int ghes_probe(struct platform_device *ghes_dev)
1323{
1324	struct acpi_hest_generic *generic;
1325	struct ghes *ghes = NULL;
1326	unsigned long flags;
1327
1328	int rc = -EINVAL;
1329
1330	generic = *(struct acpi_hest_generic **)ghes_dev->dev.platform_data;
1331	if (!generic->enabled)
1332		return -ENODEV;
1333
1334	switch (generic->notify.type) {
1335	case ACPI_HEST_NOTIFY_POLLED:
1336	case ACPI_HEST_NOTIFY_EXTERNAL:
1337	case ACPI_HEST_NOTIFY_SCI:
1338	case ACPI_HEST_NOTIFY_GSIV:
1339	case ACPI_HEST_NOTIFY_GPIO:
1340		break;
1341
1342	case ACPI_HEST_NOTIFY_SEA:
1343		if (!IS_ENABLED(CONFIG_ACPI_APEI_SEA)) {
1344			pr_warn(GHES_PFX "Generic hardware error source: %d notified via SEA is not supported\n",
1345				generic->header.source_id);
1346			rc = -ENOTSUPP;
1347			goto err;
1348		}
1349		break;
1350	case ACPI_HEST_NOTIFY_NMI:
1351		if (!IS_ENABLED(CONFIG_HAVE_ACPI_APEI_NMI)) {
1352			pr_warn(GHES_PFX "Generic hardware error source: %d notified via NMI interrupt is not supported!\n",
1353				generic->header.source_id);
1354			goto err;
1355		}
1356		break;
1357	case ACPI_HEST_NOTIFY_SOFTWARE_DELEGATED:
1358		if (!IS_ENABLED(CONFIG_ARM_SDE_INTERFACE)) {
1359			pr_warn(GHES_PFX "Generic hardware error source: %d notified via SDE Interface is not supported!\n",
1360				generic->header.source_id);
1361			goto err;
1362		}
1363		break;
1364	case ACPI_HEST_NOTIFY_LOCAL:
1365		pr_warn(GHES_PFX "Generic hardware error source: %d notified via local interrupt is not supported!\n",
1366			generic->header.source_id);
1367		goto err;
1368	default:
1369		pr_warn(FW_WARN GHES_PFX "Unknown notification type: %u for generic hardware error source: %d\n",
1370			generic->notify.type, generic->header.source_id);
1371		goto err;
1372	}
1373
1374	rc = -EIO;
1375	if (generic->error_block_length <
1376	    sizeof(struct acpi_hest_generic_status)) {
1377		pr_warn(FW_BUG GHES_PFX "Invalid error block length: %u for generic hardware error source: %d\n",
1378			generic->error_block_length, generic->header.source_id);
1379		goto err;
1380	}
1381	ghes = ghes_new(generic);
1382	if (IS_ERR(ghes)) {
1383		rc = PTR_ERR(ghes);
1384		ghes = NULL;
1385		goto err;
1386	}
1387
1388	switch (generic->notify.type) {
1389	case ACPI_HEST_NOTIFY_POLLED:
1390		timer_setup(&ghes->timer, ghes_poll_func, 0);
1391		ghes_add_timer(ghes);
1392		break;
1393	case ACPI_HEST_NOTIFY_EXTERNAL:
1394		/* External interrupt vector is GSI */
1395		rc = acpi_gsi_to_irq(generic->notify.vector, &ghes->irq);
1396		if (rc) {
1397			pr_err(GHES_PFX "Failed to map GSI to IRQ for generic hardware error source: %d\n",
1398			       generic->header.source_id);
1399			goto err;
1400		}
1401		rc = request_irq(ghes->irq, ghes_irq_func, IRQF_SHARED,
1402				 "GHES IRQ", ghes);
1403		if (rc) {
1404			pr_err(GHES_PFX "Failed to register IRQ for generic hardware error source: %d\n",
1405			       generic->header.source_id);
1406			goto err;
1407		}
1408		break;
1409
1410	case ACPI_HEST_NOTIFY_SCI:
1411	case ACPI_HEST_NOTIFY_GSIV:
1412	case ACPI_HEST_NOTIFY_GPIO:
1413		mutex_lock(&ghes_list_mutex);
1414		if (list_empty(&ghes_hed))
1415			register_acpi_hed_notifier(&ghes_notifier_hed);
1416		list_add_rcu(&ghes->list, &ghes_hed);
1417		mutex_unlock(&ghes_list_mutex);
1418		break;
1419
1420	case ACPI_HEST_NOTIFY_SEA:
1421		ghes_sea_add(ghes);
1422		break;
1423	case ACPI_HEST_NOTIFY_NMI:
1424		ghes_nmi_add(ghes);
1425		break;
1426	case ACPI_HEST_NOTIFY_SOFTWARE_DELEGATED:
1427		rc = apei_sdei_register_ghes(ghes);
1428		if (rc)
1429			goto err;
1430		break;
1431	default:
1432		BUG();
1433	}
1434
1435	platform_set_drvdata(ghes_dev, ghes);
1436
1437	ghes->dev = &ghes_dev->dev;
1438
1439	mutex_lock(&ghes_devs_mutex);
1440	list_add_tail(&ghes->elist, &ghes_devs);
1441	mutex_unlock(&ghes_devs_mutex);
1442
1443	/* Handle any pending errors right away */
1444	spin_lock_irqsave(&ghes_notify_lock_irq, flags);
1445	ghes_proc(ghes);
1446	spin_unlock_irqrestore(&ghes_notify_lock_irq, flags);
1447
1448	return 0;
1449
1450err:
1451	if (ghes) {
1452		ghes_fini(ghes);
1453		kfree(ghes);
1454	}
1455	return rc;
1456}
1457
1458static int ghes_remove(struct platform_device *ghes_dev)
1459{
1460	int rc;
1461	struct ghes *ghes;
1462	struct acpi_hest_generic *generic;
1463
1464	ghes = platform_get_drvdata(ghes_dev);
1465	generic = ghes->generic;
1466
1467	ghes->flags |= GHES_EXITING;
1468	switch (generic->notify.type) {
1469	case ACPI_HEST_NOTIFY_POLLED:
1470		timer_shutdown_sync(&ghes->timer);
1471		break;
1472	case ACPI_HEST_NOTIFY_EXTERNAL:
1473		free_irq(ghes->irq, ghes);
1474		break;
1475
1476	case ACPI_HEST_NOTIFY_SCI:
1477	case ACPI_HEST_NOTIFY_GSIV:
1478	case ACPI_HEST_NOTIFY_GPIO:
1479		mutex_lock(&ghes_list_mutex);
1480		list_del_rcu(&ghes->list);
1481		if (list_empty(&ghes_hed))
1482			unregister_acpi_hed_notifier(&ghes_notifier_hed);
1483		mutex_unlock(&ghes_list_mutex);
1484		synchronize_rcu();
1485		break;
1486
1487	case ACPI_HEST_NOTIFY_SEA:
1488		ghes_sea_remove(ghes);
1489		break;
1490	case ACPI_HEST_NOTIFY_NMI:
1491		ghes_nmi_remove(ghes);
1492		break;
1493	case ACPI_HEST_NOTIFY_SOFTWARE_DELEGATED:
1494		rc = apei_sdei_unregister_ghes(ghes);
1495		if (rc)
1496			return rc;
1497		break;
1498	default:
1499		BUG();
1500		break;
1501	}
1502
1503	ghes_fini(ghes);
1504
1505	mutex_lock(&ghes_devs_mutex);
1506	list_del(&ghes->elist);
1507	mutex_unlock(&ghes_devs_mutex);
1508
1509	kfree(ghes);
1510
 
 
1511	return 0;
1512}
1513
1514static struct platform_driver ghes_platform_driver = {
1515	.driver		= {
1516		.name	= "GHES",
1517	},
1518	.probe		= ghes_probe,
1519	.remove		= ghes_remove,
1520};
1521
1522void __init acpi_ghes_init(void)
1523{
1524	int rc;
1525
1526	sdei_init();
1527
1528	if (acpi_disabled)
1529		return;
1530
1531	switch (hest_disable) {
1532	case HEST_NOT_FOUND:
1533		return;
1534	case HEST_DISABLED:
1535		pr_info(GHES_PFX "HEST is not enabled!\n");
1536		return;
1537	default:
1538		break;
1539	}
1540
1541	if (ghes_disable) {
1542		pr_info(GHES_PFX "GHES is not enabled!\n");
1543		return;
1544	}
1545
1546	ghes_nmi_init_cxt();
1547
1548	rc = platform_driver_register(&ghes_platform_driver);
1549	if (rc)
1550		return;
1551
1552	rc = apei_osc_setup();
1553	if (rc == 0 && osc_sb_apei_support_acked)
1554		pr_info(GHES_PFX "APEI firmware first mode is enabled by APEI bit and WHEA _OSC.\n");
1555	else if (rc == 0 && !osc_sb_apei_support_acked)
1556		pr_info(GHES_PFX "APEI firmware first mode is enabled by WHEA _OSC.\n");
1557	else if (rc && osc_sb_apei_support_acked)
1558		pr_info(GHES_PFX "APEI firmware first mode is enabled by APEI bit.\n");
1559	else
1560		pr_info(GHES_PFX "Failed to enable APEI firmware first mode.\n");
1561}
1562
1563/*
1564 * Known x86 systems that prefer GHES error reporting:
1565 */
1566static struct acpi_platform_list plat_list[] = {
1567	{"HPE   ", "Server  ", 0, ACPI_SIG_FADT, all_versions},
1568	{ } /* End */
1569};
1570
1571struct list_head *ghes_get_devices(void)
1572{
1573	int idx = -1;
1574
1575	if (IS_ENABLED(CONFIG_X86)) {
1576		idx = acpi_match_platform_list(plat_list);
1577		if (idx < 0) {
1578			if (!ghes_edac_force_enable)
1579				return NULL;
1580
1581			pr_warn_once("Force-loading ghes_edac on an unsupported platform. You're on your own!\n");
1582		}
1583	} else if (list_empty(&ghes_devs)) {
1584		return NULL;
1585	}
1586
1587	return &ghes_devs;
1588}
1589EXPORT_SYMBOL_GPL(ghes_get_devices);
1590
1591void ghes_register_report_chain(struct notifier_block *nb)
1592{
1593	atomic_notifier_chain_register(&ghes_report_chain, nb);
1594}
1595EXPORT_SYMBOL_GPL(ghes_register_report_chain);
1596
1597void ghes_unregister_report_chain(struct notifier_block *nb)
1598{
1599	atomic_notifier_chain_unregister(&ghes_report_chain, nb);
1600}
1601EXPORT_SYMBOL_GPL(ghes_unregister_report_chain);