1 /*
2  * Copyright (c) 2008 Intel Corporation
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice (including the next
12  * paragraph) shall be included in all copies or substantial portions of the
13  * Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21  * IN THE SOFTWARE.
22  *
23  * Authors:
24  *    Eric Anholt <eric@anholt.net>
25  *    Keith Packard <keithp@keithp.com>
26  *    Mika Kuoppala <mika.kuoppala@intel.com>
27  *
28  */
29 
30 #include <linux/ascii85.h>
31 #include <linux/nmi.h>
32 #include <linux/scatterlist.h>
33 #include <linux/stop_machine.h>
34 #include <linux/utsname.h>
35 #include <linux/zlib.h>
36 
37 #include <drm/drm_print.h>
38 
39 #include "i915_gpu_error.h"
40 #include "i915_drv.h"
41 
42 static inline const struct intel_engine_cs *
43 engine_lookup(const struct drm_i915_private *i915, unsigned int id)
44 {
45 	if (id >= I915_NUM_ENGINES)
46 		return NULL;
47 
48 	return i915->engine[id];
49 }
50 
51 static inline const char *
52 __engine_name(const struct intel_engine_cs *engine)
53 {
54 	return engine ? engine->name : "";
55 }
56 
57 static const char *
58 engine_name(const struct drm_i915_private *i915, unsigned int id)
59 {
60 	return __engine_name(engine_lookup(i915, id));
61 }
62 
63 static const char *tiling_flag(int tiling)
64 {
65 	switch (tiling) {
66 	default:
67 	case I915_TILING_NONE: return "";
68 	case I915_TILING_X: return " X";
69 	case I915_TILING_Y: return " Y";
70 	}
71 }
72 
73 static const char *dirty_flag(int dirty)
74 {
75 	return dirty ? " dirty" : "";
76 }
77 
78 static const char *purgeable_flag(int purgeable)
79 {
80 	return purgeable ? " purgeable" : "";
81 }
82 
83 static void __sg_set_buf(struct scatterlist *sg,
84 			 void *addr, unsigned int len, loff_t it)
85 {
86 	sg->page_link = (unsigned long)virt_to_page(addr);
87 	sg->offset = offset_in_page(addr);
88 	sg->length = len;
89 	sg->dma_address = it;
90 }
91 
92 static bool __i915_error_grow(struct drm_i915_error_state_buf *e, size_t len)
93 {
94 	if (!len)
95 		return false;
96 
97 	if (e->bytes + len + 1 <= e->size)
98 		return true;
99 
100 	if (e->bytes) {
101 		__sg_set_buf(e->cur++, e->buf, e->bytes, e->iter);
102 		e->iter += e->bytes;
103 		e->buf = NULL;
104 		e->bytes = 0;
105 	}
106 
107 	if (e->cur == e->end) {
108 		struct scatterlist *sgl;
109 
110 		sgl = (typeof(sgl))__get_free_page(GFP_KERNEL);
111 		if (!sgl) {
112 			e->err = -ENOMEM;
113 			return false;
114 		}
115 
116 		if (e->cur) {
117 			e->cur->offset = 0;
118 			e->cur->length = 0;
119 			e->cur->page_link =
120 				(unsigned long)sgl | SG_CHAIN;
121 		} else {
122 			e->sgl = sgl;
123 		}
124 
125 		e->cur = sgl;
126 		e->end = sgl + SG_MAX_SINGLE_ALLOC - 1;
127 	}
128 
129 	e->size = ALIGN(len + 1, SZ_64K);
130 	e->buf = kmalloc(e->size, GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY);
131 	if (!e->buf) {
132 		e->size = PAGE_ALIGN(len + 1);
133 		e->buf = kmalloc(e->size, GFP_KERNEL);
134 	}
135 	if (!e->buf) {
136 		e->err = -ENOMEM;
137 		return false;
138 	}
139 
140 	return true;
141 }
142 
143 __printf(2, 0)
144 static void i915_error_vprintf(struct drm_i915_error_state_buf *e,
145 			       const char *fmt, va_list args)
146 {
147 	va_list ap;
148 	int len;
149 
150 	if (e->err)
151 		return;
152 
153 	va_copy(ap, args);
154 	len = vsnprintf(NULL, 0, fmt, ap);
155 	va_end(ap);
156 	if (len <= 0) {
157 		e->err = len;
158 		return;
159 	}
160 
161 	if (!__i915_error_grow(e, len))
162 		return;
163 
164 	GEM_BUG_ON(e->bytes >= e->size);
165 	len = vscnprintf(e->buf + e->bytes, e->size - e->bytes, fmt, args);
166 	if (len < 0) {
167 		e->err = len;
168 		return;
169 	}
170 	e->bytes += len;
171 }
172 
173 static void i915_error_puts(struct drm_i915_error_state_buf *e, const char *str)
174 {
175 	unsigned len;
176 
177 	if (e->err || !str)
178 		return;
179 
180 	len = strlen(str);
181 	if (!__i915_error_grow(e, len))
182 		return;
183 
184 	GEM_BUG_ON(e->bytes + len > e->size);
185 	memcpy(e->buf + e->bytes, str, len);
186 	e->bytes += len;
187 }
188 
189 #define err_printf(e, ...) i915_error_printf(e, __VA_ARGS__)
190 #define err_puts(e, s) i915_error_puts(e, s)
191 
192 static void __i915_printfn_error(struct drm_printer *p, struct va_format *vaf)
193 {
194 	i915_error_vprintf(p->arg, vaf->fmt, *vaf->va);
195 }
196 
197 static inline struct drm_printer
198 i915_error_printer(struct drm_i915_error_state_buf *e)
199 {
200 	struct drm_printer p = {
201 		.printfn = __i915_printfn_error,
202 		.arg = e,
203 	};
204 	return p;
205 }
206 
207 #ifdef CONFIG_DRM_I915_COMPRESS_ERROR
208 
209 struct compress {
210 	struct z_stream_s zstream;
211 	void *tmp;
212 };
213 
214 static bool compress_init(struct compress *c)
215 {
216 	struct z_stream_s *zstream = memset(&c->zstream, 0, sizeof(c->zstream));
217 
218 	zstream->workspace =
219 		kmalloc(zlib_deflate_workspacesize(MAX_WBITS, MAX_MEM_LEVEL),
220 			GFP_ATOMIC | __GFP_NOWARN);
221 	if (!zstream->workspace)
222 		return false;
223 
224 	if (zlib_deflateInit(zstream, Z_DEFAULT_COMPRESSION) != Z_OK) {
225 		kfree(zstream->workspace);
226 		return false;
227 	}
228 
229 	c->tmp = NULL;
230 	if (i915_has_memcpy_from_wc())
231 		c->tmp = (void *)__get_free_page(GFP_ATOMIC | __GFP_NOWARN);
232 
233 	return true;
234 }
235 
236 static void *compress_next_page(struct drm_i915_error_object *dst)
237 {
238 	unsigned long page;
239 
240 	if (dst->page_count >= dst->num_pages)
241 		return ERR_PTR(-ENOSPC);
242 
243 	page = __get_free_page(GFP_ATOMIC | __GFP_NOWARN);
244 	if (!page)
245 		return ERR_PTR(-ENOMEM);
246 
247 	return dst->pages[dst->page_count++] = (void *)page;
248 }
249 
250 static int compress_page(struct compress *c,
251 			 void *src,
252 			 struct drm_i915_error_object *dst)
253 {
254 	struct z_stream_s *zstream = &c->zstream;
255 
256 	zstream->next_in = src;
257 	if (c->tmp && i915_memcpy_from_wc(c->tmp, src, PAGE_SIZE))
258 		zstream->next_in = c->tmp;
259 	zstream->avail_in = PAGE_SIZE;
260 
261 	do {
262 		if (zstream->avail_out == 0) {
263 			zstream->next_out = compress_next_page(dst);
264 			if (IS_ERR(zstream->next_out))
265 				return PTR_ERR(zstream->next_out);
266 
267 			zstream->avail_out = PAGE_SIZE;
268 		}
269 
270 		if (zlib_deflate(zstream, Z_NO_FLUSH) != Z_OK)
271 			return -EIO;
272 
273 		touch_nmi_watchdog();
274 	} while (zstream->avail_in);
275 
276 	/* Fallback to uncompressed if we increase size? */
277 	if (0 && zstream->total_out > zstream->total_in)
278 		return -E2BIG;
279 
280 	return 0;
281 }
282 
283 static int compress_flush(struct compress *c,
284 			  struct drm_i915_error_object *dst)
285 {
286 	struct z_stream_s *zstream = &c->zstream;
287 
288 	do {
289 		switch (zlib_deflate(zstream, Z_FINISH)) {
290 		case Z_OK: /* more space requested */
291 			zstream->next_out = compress_next_page(dst);
292 			if (IS_ERR(zstream->next_out))
293 				return PTR_ERR(zstream->next_out);
294 
295 			zstream->avail_out = PAGE_SIZE;
296 			break;
297 
298 		case Z_STREAM_END:
299 			goto end;
300 
301 		default: /* any error */
302 			return -EIO;
303 		}
304 	} while (1);
305 
306 end:
307 	memset(zstream->next_out, 0, zstream->avail_out);
308 	dst->unused = zstream->avail_out;
309 	return 0;
310 }
311 
312 static void compress_fini(struct compress *c,
313 			  struct drm_i915_error_object *dst)
314 {
315 	struct z_stream_s *zstream = &c->zstream;
316 
317 	zlib_deflateEnd(zstream);
318 	kfree(zstream->workspace);
319 	if (c->tmp)
320 		free_page((unsigned long)c->tmp);
321 }
322 
323 static void err_compression_marker(struct drm_i915_error_state_buf *m)
324 {
325 	err_puts(m, ":");
326 }
327 
328 #else
329 
330 struct compress {
331 };
332 
333 static bool compress_init(struct compress *c)
334 {
335 	return true;
336 }
337 
338 static int compress_page(struct compress *c,
339 			 void *src,
340 			 struct drm_i915_error_object *dst)
341 {
342 	unsigned long page;
343 	void *ptr;
344 
345 	page = __get_free_page(GFP_ATOMIC | __GFP_NOWARN);
346 	if (!page)
347 		return -ENOMEM;
348 
349 	ptr = (void *)page;
350 	if (!i915_memcpy_from_wc(ptr, src, PAGE_SIZE))
351 		memcpy(ptr, src, PAGE_SIZE);
352 	dst->pages[dst->page_count++] = ptr;
353 
354 	return 0;
355 }
356 
357 static int compress_flush(struct compress *c,
358 			  struct drm_i915_error_object *dst)
359 {
360 	return 0;
361 }
362 
363 static void compress_fini(struct compress *c,
364 			  struct drm_i915_error_object *dst)
365 {
366 }
367 
368 static void err_compression_marker(struct drm_i915_error_state_buf *m)
369 {
370 	err_puts(m, "~");
371 }
372 
373 #endif
374 
375 static void print_error_buffers(struct drm_i915_error_state_buf *m,
376 				const char *name,
377 				struct drm_i915_error_buffer *err,
378 				int count)
379 {
380 	err_printf(m, "%s [%d]:\n", name, count);
381 
382 	while (count--) {
383 		err_printf(m, "    %08x_%08x %8u %02x %02x %02x",
384 			   upper_32_bits(err->gtt_offset),
385 			   lower_32_bits(err->gtt_offset),
386 			   err->size,
387 			   err->read_domains,
388 			   err->write_domain,
389 			   err->wseqno);
390 		err_puts(m, tiling_flag(err->tiling));
391 		err_puts(m, dirty_flag(err->dirty));
392 		err_puts(m, purgeable_flag(err->purgeable));
393 		err_puts(m, err->userptr ? " userptr" : "");
394 		err_puts(m, err->engine != -1 ? " " : "");
395 		err_puts(m, engine_name(m->i915, err->engine));
396 		err_puts(m, i915_cache_level_str(m->i915, err->cache_level));
397 
398 		if (err->name)
399 			err_printf(m, " (name: %d)", err->name);
400 		if (err->fence_reg != I915_FENCE_REG_NONE)
401 			err_printf(m, " (fence: %d)", err->fence_reg);
402 
403 		err_puts(m, "\n");
404 		err++;
405 	}
406 }
407 
408 static void error_print_instdone(struct drm_i915_error_state_buf *m,
409 				 const struct drm_i915_error_engine *ee)
410 {
411 	int slice;
412 	int subslice;
413 
414 	err_printf(m, "  INSTDONE: 0x%08x\n",
415 		   ee->instdone.instdone);
416 
417 	if (ee->engine_id != RCS || INTEL_GEN(m->i915) <= 3)
418 		return;
419 
420 	err_printf(m, "  SC_INSTDONE: 0x%08x\n",
421 		   ee->instdone.slice_common);
422 
423 	if (INTEL_GEN(m->i915) <= 6)
424 		return;
425 
426 	for_each_instdone_slice_subslice(m->i915, slice, subslice)
427 		err_printf(m, "  SAMPLER_INSTDONE[%d][%d]: 0x%08x\n",
428 			   slice, subslice,
429 			   ee->instdone.sampler[slice][subslice]);
430 
431 	for_each_instdone_slice_subslice(m->i915, slice, subslice)
432 		err_printf(m, "  ROW_INSTDONE[%d][%d]: 0x%08x\n",
433 			   slice, subslice,
434 			   ee->instdone.row[slice][subslice]);
435 }
436 
437 static const char *bannable(const struct drm_i915_error_context *ctx)
438 {
439 	return ctx->bannable ? "" : " (unbannable)";
440 }
441 
442 static void error_print_request(struct drm_i915_error_state_buf *m,
443 				const char *prefix,
444 				const struct drm_i915_error_request *erq,
445 				const unsigned long epoch)
446 {
447 	if (!erq->seqno)
448 		return;
449 
450 	err_printf(m, "%s pid %d, ban score %d, seqno %8x:%08x, prio %d, emitted %dms, start %08x, head %08x, tail %08x\n",
451 		   prefix, erq->pid, erq->ban_score,
452 		   erq->context, erq->seqno, erq->sched_attr.priority,
453 		   jiffies_to_msecs(erq->jiffies - epoch),
454 		   erq->start, erq->head, erq->tail);
455 }
456 
457 static void error_print_context(struct drm_i915_error_state_buf *m,
458 				const char *header,
459 				const struct drm_i915_error_context *ctx)
460 {
461 	err_printf(m, "%s%s[%d] user_handle %d hw_id %d, prio %d, ban score %d%s guilty %d active %d\n",
462 		   header, ctx->comm, ctx->pid, ctx->handle, ctx->hw_id,
463 		   ctx->sched_attr.priority, ctx->ban_score, bannable(ctx),
464 		   ctx->guilty, ctx->active);
465 }
466 
467 static void error_print_engine(struct drm_i915_error_state_buf *m,
468 			       const struct drm_i915_error_engine *ee,
469 			       const unsigned long epoch)
470 {
471 	int n;
472 
473 	err_printf(m, "%s command stream:\n",
474 		   engine_name(m->i915, ee->engine_id));
475 	err_printf(m, "  IDLE?: %s\n", yesno(ee->idle));
476 	err_printf(m, "  START: 0x%08x\n", ee->start);
477 	err_printf(m, "  HEAD:  0x%08x [0x%08x]\n", ee->head, ee->rq_head);
478 	err_printf(m, "  TAIL:  0x%08x [0x%08x, 0x%08x]\n",
479 		   ee->tail, ee->rq_post, ee->rq_tail);
480 	err_printf(m, "  CTL:   0x%08x\n", ee->ctl);
481 	err_printf(m, "  MODE:  0x%08x\n", ee->mode);
482 	err_printf(m, "  HWS:   0x%08x\n", ee->hws);
483 	err_printf(m, "  ACTHD: 0x%08x %08x\n",
484 		   (u32)(ee->acthd>>32), (u32)ee->acthd);
485 	err_printf(m, "  IPEIR: 0x%08x\n", ee->ipeir);
486 	err_printf(m, "  IPEHR: 0x%08x\n", ee->ipehr);
487 
488 	error_print_instdone(m, ee);
489 
490 	if (ee->batchbuffer) {
491 		u64 start = ee->batchbuffer->gtt_offset;
492 		u64 end = start + ee->batchbuffer->gtt_size;
493 
494 		err_printf(m, "  batch: [0x%08x_%08x, 0x%08x_%08x]\n",
495 			   upper_32_bits(start), lower_32_bits(start),
496 			   upper_32_bits(end), lower_32_bits(end));
497 	}
498 	if (INTEL_GEN(m->i915) >= 4) {
499 		err_printf(m, "  BBADDR: 0x%08x_%08x\n",
500 			   (u32)(ee->bbaddr>>32), (u32)ee->bbaddr);
501 		err_printf(m, "  BB_STATE: 0x%08x\n", ee->bbstate);
502 		err_printf(m, "  INSTPS: 0x%08x\n", ee->instps);
503 	}
504 	err_printf(m, "  INSTPM: 0x%08x\n", ee->instpm);
505 	err_printf(m, "  FADDR: 0x%08x %08x\n", upper_32_bits(ee->faddr),
506 		   lower_32_bits(ee->faddr));
507 	if (INTEL_GEN(m->i915) >= 6) {
508 		err_printf(m, "  RC PSMI: 0x%08x\n", ee->rc_psmi);
509 		err_printf(m, "  FAULT_REG: 0x%08x\n", ee->fault_reg);
510 		err_printf(m, "  SYNC_0: 0x%08x\n",
511 			   ee->semaphore_mboxes[0]);
512 		err_printf(m, "  SYNC_1: 0x%08x\n",
513 			   ee->semaphore_mboxes[1]);
514 		if (HAS_VEBOX(m->i915))
515 			err_printf(m, "  SYNC_2: 0x%08x\n",
516 				   ee->semaphore_mboxes[2]);
517 	}
518 	if (HAS_PPGTT(m->i915)) {
519 		err_printf(m, "  GFX_MODE: 0x%08x\n", ee->vm_info.gfx_mode);
520 
521 		if (INTEL_GEN(m->i915) >= 8) {
522 			int i;
523 			for (i = 0; i < 4; i++)
524 				err_printf(m, "  PDP%d: 0x%016llx\n",
525 					   i, ee->vm_info.pdp[i]);
526 		} else {
527 			err_printf(m, "  PP_DIR_BASE: 0x%08x\n",
528 				   ee->vm_info.pp_dir_base);
529 		}
530 	}
531 	err_printf(m, "  seqno: 0x%08x\n", ee->seqno);
532 	err_printf(m, "  last_seqno: 0x%08x\n", ee->last_seqno);
533 	err_printf(m, "  waiting: %s\n", yesno(ee->waiting));
534 	err_printf(m, "  ring->head: 0x%08x\n", ee->cpu_ring_head);
535 	err_printf(m, "  ring->tail: 0x%08x\n", ee->cpu_ring_tail);
536 	err_printf(m, "  hangcheck stall: %s\n", yesno(ee->hangcheck_stalled));
537 	err_printf(m, "  hangcheck action: %s\n",
538 		   hangcheck_action_to_str(ee->hangcheck_action));
539 	err_printf(m, "  hangcheck action timestamp: %dms (%lu%s)\n",
540 		   jiffies_to_msecs(ee->hangcheck_timestamp - epoch),
541 		   ee->hangcheck_timestamp,
542 		   ee->hangcheck_timestamp == epoch ? "; epoch" : "");
543 	err_printf(m, "  engine reset count: %u\n", ee->reset_count);
544 
545 	for (n = 0; n < ee->num_ports; n++) {
546 		err_printf(m, "  ELSP[%d]:", n);
547 		error_print_request(m, " ", &ee->execlist[n], epoch);
548 	}
549 
550 	error_print_context(m, "  Active context: ", &ee->context);
551 }
552 
553 void i915_error_printf(struct drm_i915_error_state_buf *e, const char *f, ...)
554 {
555 	va_list args;
556 
557 	va_start(args, f);
558 	i915_error_vprintf(e, f, args);
559 	va_end(args);
560 }
561 
562 static void print_error_obj(struct drm_i915_error_state_buf *m,
563 			    struct intel_engine_cs *engine,
564 			    const char *name,
565 			    struct drm_i915_error_object *obj)
566 {
567 	char out[ASCII85_BUFSZ];
568 	int page;
569 
570 	if (!obj)
571 		return;
572 
573 	if (name) {
574 		err_printf(m, "%s --- %s = 0x%08x %08x\n",
575 			   engine ? engine->name : "global", name,
576 			   upper_32_bits(obj->gtt_offset),
577 			   lower_32_bits(obj->gtt_offset));
578 	}
579 
580 	err_compression_marker(m);
581 	for (page = 0; page < obj->page_count; page++) {
582 		int i, len;
583 
584 		len = PAGE_SIZE;
585 		if (page == obj->page_count - 1)
586 			len -= obj->unused;
587 		len = ascii85_encode_len(len);
588 
589 		for (i = 0; i < len; i++)
590 			err_puts(m, ascii85_encode(obj->pages[page][i], out));
591 	}
592 	err_puts(m, "\n");
593 }
594 
595 static void err_print_capabilities(struct drm_i915_error_state_buf *m,
596 				   const struct intel_device_info *info,
597 				   const struct intel_driver_caps *caps)
598 {
599 	struct drm_printer p = i915_error_printer(m);
600 
601 	intel_device_info_dump_flags(info, &p);
602 	intel_driver_caps_print(caps, &p);
603 	intel_device_info_dump_topology(&info->sseu, &p);
604 }
605 
606 static void err_print_params(struct drm_i915_error_state_buf *m,
607 			     const struct i915_params *params)
608 {
609 	struct drm_printer p = i915_error_printer(m);
610 
611 	i915_params_dump(params, &p);
612 }
613 
614 static void err_print_pciid(struct drm_i915_error_state_buf *m,
615 			    struct drm_i915_private *i915)
616 {
617 	struct pci_dev *pdev = i915->drm.pdev;
618 
619 	err_printf(m, "PCI ID: 0x%04x\n", pdev->device);
620 	err_printf(m, "PCI Revision: 0x%02x\n", pdev->revision);
621 	err_printf(m, "PCI Subsystem: %04x:%04x\n",
622 		   pdev->subsystem_vendor,
623 		   pdev->subsystem_device);
624 }
625 
626 static void err_print_uc(struct drm_i915_error_state_buf *m,
627 			 const struct i915_error_uc *error_uc)
628 {
629 	struct drm_printer p = i915_error_printer(m);
630 	const struct i915_gpu_state *error =
631 		container_of(error_uc, typeof(*error), uc);
632 
633 	if (!error->device_info.has_guc)
634 		return;
635 
636 	intel_uc_fw_dump(&error_uc->guc_fw, &p);
637 	intel_uc_fw_dump(&error_uc->huc_fw, &p);
638 	print_error_obj(m, NULL, "GuC log buffer", error_uc->guc_log);
639 }
640 
641 static void err_free_sgl(struct scatterlist *sgl)
642 {
643 	while (sgl) {
644 		struct scatterlist *sg;
645 
646 		for (sg = sgl; !sg_is_chain(sg); sg++) {
647 			kfree(sg_virt(sg));
648 			if (sg_is_last(sg))
649 				break;
650 		}
651 
652 		sg = sg_is_last(sg) ? NULL : sg_chain_ptr(sg);
653 		free_page((unsigned long)sgl);
654 		sgl = sg;
655 	}
656 }
657 
658 static void __err_print_to_sgl(struct drm_i915_error_state_buf *m,
659 			       struct i915_gpu_state *error)
660 {
661 	struct drm_i915_error_object *obj;
662 	struct timespec64 ts;
663 	int i, j;
664 
665 	if (*error->error_msg)
666 		err_printf(m, "%s\n", error->error_msg);
667 	err_printf(m, "Kernel: %s\n", init_utsname()->release);
668 	ts = ktime_to_timespec64(error->time);
669 	err_printf(m, "Time: %lld s %ld us\n",
670 		   (s64)ts.tv_sec, ts.tv_nsec / NSEC_PER_USEC);
671 	ts = ktime_to_timespec64(error->boottime);
672 	err_printf(m, "Boottime: %lld s %ld us\n",
673 		   (s64)ts.tv_sec, ts.tv_nsec / NSEC_PER_USEC);
674 	ts = ktime_to_timespec64(error->uptime);
675 	err_printf(m, "Uptime: %lld s %ld us\n",
676 		   (s64)ts.tv_sec, ts.tv_nsec / NSEC_PER_USEC);
677 	err_printf(m, "Epoch: %lu jiffies (%u HZ)\n", error->epoch, HZ);
678 	err_printf(m, "Capture: %lu jiffies; %d ms ago, %d ms after epoch\n",
679 		   error->capture,
680 		   jiffies_to_msecs(jiffies - error->capture),
681 		   jiffies_to_msecs(error->capture - error->epoch));
682 
683 	for (i = 0; i < ARRAY_SIZE(error->engine); i++) {
684 		if (error->engine[i].hangcheck_stalled &&
685 		    error->engine[i].context.pid) {
686 			err_printf(m, "Active process (on ring %s): %s [%d], score %d%s\n",
687 				   engine_name(m->i915, i),
688 				   error->engine[i].context.comm,
689 				   error->engine[i].context.pid,
690 				   error->engine[i].context.ban_score,
691 				   bannable(&error->engine[i].context));
692 		}
693 	}
694 	err_printf(m, "Reset count: %u\n", error->reset_count);
695 	err_printf(m, "Suspend count: %u\n", error->suspend_count);
696 	err_printf(m, "Platform: %s\n", intel_platform_name(error->device_info.platform));
697 	err_print_pciid(m, m->i915);
698 
699 	err_printf(m, "IOMMU enabled?: %d\n", error->iommu);
700 
701 	if (HAS_CSR(m->i915)) {
702 		struct intel_csr *csr = &m->i915->csr;
703 
704 		err_printf(m, "DMC loaded: %s\n",
705 			   yesno(csr->dmc_payload != NULL));
706 		err_printf(m, "DMC fw version: %d.%d\n",
707 			   CSR_VERSION_MAJOR(csr->version),
708 			   CSR_VERSION_MINOR(csr->version));
709 	}
710 
711 	err_printf(m, "GT awake: %s\n", yesno(error->awake));
712 	err_printf(m, "RPM wakelock: %s\n", yesno(error->wakelock));
713 	err_printf(m, "PM suspended: %s\n", yesno(error->suspended));
714 	err_printf(m, "EIR: 0x%08x\n", error->eir);
715 	err_printf(m, "IER: 0x%08x\n", error->ier);
716 	for (i = 0; i < error->ngtier; i++)
717 		err_printf(m, "GTIER[%d]: 0x%08x\n", i, error->gtier[i]);
718 	err_printf(m, "PGTBL_ER: 0x%08x\n", error->pgtbl_er);
719 	err_printf(m, "FORCEWAKE: 0x%08x\n", error->forcewake);
720 	err_printf(m, "DERRMR: 0x%08x\n", error->derrmr);
721 	err_printf(m, "CCID: 0x%08x\n", error->ccid);
722 	err_printf(m, "Missed interrupts: 0x%08lx\n",
723 		   m->i915->gpu_error.missed_irq_rings);
724 
725 	for (i = 0; i < error->nfence; i++)
726 		err_printf(m, "  fence[%d] = %08llx\n", i, error->fence[i]);
727 
728 	if (INTEL_GEN(m->i915) >= 6) {
729 		err_printf(m, "ERROR: 0x%08x\n", error->error);
730 
731 		if (INTEL_GEN(m->i915) >= 8)
732 			err_printf(m, "FAULT_TLB_DATA: 0x%08x 0x%08x\n",
733 				   error->fault_data1, error->fault_data0);
734 
735 		err_printf(m, "DONE_REG: 0x%08x\n", error->done_reg);
736 	}
737 
738 	if (IS_GEN7(m->i915))
739 		err_printf(m, "ERR_INT: 0x%08x\n", error->err_int);
740 
741 	for (i = 0; i < ARRAY_SIZE(error->engine); i++) {
742 		if (error->engine[i].engine_id != -1)
743 			error_print_engine(m, &error->engine[i], error->epoch);
744 	}
745 
746 	for (i = 0; i < ARRAY_SIZE(error->active_vm); i++) {
747 		char buf[128];
748 		int len, first = 1;
749 
750 		if (!error->active_vm[i])
751 			break;
752 
753 		len = scnprintf(buf, sizeof(buf), "Active (");
754 		for (j = 0; j < ARRAY_SIZE(error->engine); j++) {
755 			if (error->engine[j].vm != error->active_vm[i])
756 				continue;
757 
758 			len += scnprintf(buf + len, sizeof(buf), "%s%s",
759 					 first ? "" : ", ",
760 					 m->i915->engine[j]->name);
761 			first = 0;
762 		}
763 		scnprintf(buf + len, sizeof(buf), ")");
764 		print_error_buffers(m, buf,
765 				    error->active_bo[i],
766 				    error->active_bo_count[i]);
767 	}
768 
769 	print_error_buffers(m, "Pinned (global)",
770 			    error->pinned_bo,
771 			    error->pinned_bo_count);
772 
773 	for (i = 0; i < ARRAY_SIZE(error->engine); i++) {
774 		const struct drm_i915_error_engine *ee = &error->engine[i];
775 
776 		obj = ee->batchbuffer;
777 		if (obj) {
778 			err_puts(m, m->i915->engine[i]->name);
779 			if (ee->context.pid)
780 				err_printf(m, " (submitted by %s [%d], ctx %d [%d], score %d%s)",
781 					   ee->context.comm,
782 					   ee->context.pid,
783 					   ee->context.handle,
784 					   ee->context.hw_id,
785 					   ee->context.ban_score,
786 					   bannable(&ee->context));
787 			err_printf(m, " --- gtt_offset = 0x%08x %08x\n",
788 				   upper_32_bits(obj->gtt_offset),
789 				   lower_32_bits(obj->gtt_offset));
790 			print_error_obj(m, m->i915->engine[i], NULL, obj);
791 		}
792 
793 		for (j = 0; j < ee->user_bo_count; j++)
794 			print_error_obj(m, m->i915->engine[i],
795 					"user", ee->user_bo[j]);
796 
797 		if (ee->num_requests) {
798 			err_printf(m, "%s --- %d requests\n",
799 				   m->i915->engine[i]->name,
800 				   ee->num_requests);
801 			for (j = 0; j < ee->num_requests; j++)
802 				error_print_request(m, " ",
803 						    &ee->requests[j],
804 						    error->epoch);
805 		}
806 
807 		if (IS_ERR(ee->waiters)) {
808 			err_printf(m, "%s --- ? waiters [unable to acquire spinlock]\n",
809 				   m->i915->engine[i]->name);
810 		} else if (ee->num_waiters) {
811 			err_printf(m, "%s --- %d waiters\n",
812 				   m->i915->engine[i]->name,
813 				   ee->num_waiters);
814 			for (j = 0; j < ee->num_waiters; j++) {
815 				err_printf(m, " seqno 0x%08x for %s [%d]\n",
816 					   ee->waiters[j].seqno,
817 					   ee->waiters[j].comm,
818 					   ee->waiters[j].pid);
819 			}
820 		}
821 
822 		print_error_obj(m, m->i915->engine[i],
823 				"ringbuffer", ee->ringbuffer);
824 
825 		print_error_obj(m, m->i915->engine[i],
826 				"HW Status", ee->hws_page);
827 
828 		print_error_obj(m, m->i915->engine[i],
829 				"HW context", ee->ctx);
830 
831 		print_error_obj(m, m->i915->engine[i],
832 				"WA context", ee->wa_ctx);
833 
834 		print_error_obj(m, m->i915->engine[i],
835 				"WA batchbuffer", ee->wa_batchbuffer);
836 
837 		print_error_obj(m, m->i915->engine[i],
838 				"NULL context", ee->default_state);
839 	}
840 
841 	if (error->overlay)
842 		intel_overlay_print_error_state(m, error->overlay);
843 
844 	if (error->display)
845 		intel_display_print_error_state(m, error->display);
846 
847 	err_print_capabilities(m, &error->device_info, &error->driver_caps);
848 	err_print_params(m, &error->params);
849 	err_print_uc(m, &error->uc);
850 }
851 
852 static int err_print_to_sgl(struct i915_gpu_state *error)
853 {
854 	struct drm_i915_error_state_buf m;
855 
856 	if (IS_ERR(error))
857 		return PTR_ERR(error);
858 
859 	if (READ_ONCE(error->sgl))
860 		return 0;
861 
862 	memset(&m, 0, sizeof(m));
863 	m.i915 = error->i915;
864 
865 	__err_print_to_sgl(&m, error);
866 
867 	if (m.buf) {
868 		__sg_set_buf(m.cur++, m.buf, m.bytes, m.iter);
869 		m.bytes = 0;
870 		m.buf = NULL;
871 	}
872 	if (m.cur) {
873 		GEM_BUG_ON(m.end < m.cur);
874 		sg_mark_end(m.cur - 1);
875 	}
876 	GEM_BUG_ON(m.sgl && !m.cur);
877 
878 	if (m.err) {
879 		err_free_sgl(m.sgl);
880 		return m.err;
881 	}
882 
883 	if (cmpxchg(&error->sgl, NULL, m.sgl))
884 		err_free_sgl(m.sgl);
885 
886 	return 0;
887 }
888 
889 ssize_t i915_gpu_state_copy_to_buffer(struct i915_gpu_state *error,
890 				      char *buf, loff_t off, size_t rem)
891 {
892 	struct scatterlist *sg;
893 	size_t count;
894 	loff_t pos;
895 	int err;
896 
897 	if (!error || !rem)
898 		return 0;
899 
900 	err = err_print_to_sgl(error);
901 	if (err)
902 		return err;
903 
904 	sg = READ_ONCE(error->fit);
905 	if (!sg || off < sg->dma_address)
906 		sg = error->sgl;
907 	if (!sg)
908 		return 0;
909 
910 	pos = sg->dma_address;
911 	count = 0;
912 	do {
913 		size_t len, start;
914 
915 		if (sg_is_chain(sg)) {
916 			sg = sg_chain_ptr(sg);
917 			GEM_BUG_ON(sg_is_chain(sg));
918 		}
919 
920 		len = sg->length;
921 		if (pos + len <= off) {
922 			pos += len;
923 			continue;
924 		}
925 
926 		start = sg->offset;
927 		if (pos < off) {
928 			GEM_BUG_ON(off - pos > len);
929 			len -= off - pos;
930 			start += off - pos;
931 			pos = off;
932 		}
933 
934 		len = min(len, rem);
935 		GEM_BUG_ON(!len || len > sg->length);
936 
937 		memcpy(buf, page_address(sg_page(sg)) + start, len);
938 
939 		count += len;
940 		pos += len;
941 
942 		buf += len;
943 		rem -= len;
944 		if (!rem) {
945 			WRITE_ONCE(error->fit, sg);
946 			break;
947 		}
948 	} while (!sg_is_last(sg++));
949 
950 	return count;
951 }
952 
953 static void i915_error_object_free(struct drm_i915_error_object *obj)
954 {
955 	int page;
956 
957 	if (obj == NULL)
958 		return;
959 
960 	for (page = 0; page < obj->page_count; page++)
961 		free_page((unsigned long)obj->pages[page]);
962 
963 	kfree(obj);
964 }
965 
966 static __always_inline void free_param(const char *type, void *x)
967 {
968 	if (!__builtin_strcmp(type, "char *"))
969 		kfree(*(void **)x);
970 }
971 
972 static void cleanup_params(struct i915_gpu_state *error)
973 {
974 #define FREE(T, x, ...) free_param(#T, &error->params.x);
975 	I915_PARAMS_FOR_EACH(FREE);
976 #undef FREE
977 }
978 
979 static void cleanup_uc_state(struct i915_gpu_state *error)
980 {
981 	struct i915_error_uc *error_uc = &error->uc;
982 
983 	kfree(error_uc->guc_fw.path);
984 	kfree(error_uc->huc_fw.path);
985 	i915_error_object_free(error_uc->guc_log);
986 }
987 
988 void __i915_gpu_state_free(struct kref *error_ref)
989 {
990 	struct i915_gpu_state *error =
991 		container_of(error_ref, typeof(*error), ref);
992 	long i, j;
993 
994 	for (i = 0; i < ARRAY_SIZE(error->engine); i++) {
995 		struct drm_i915_error_engine *ee = &error->engine[i];
996 
997 		for (j = 0; j < ee->user_bo_count; j++)
998 			i915_error_object_free(ee->user_bo[j]);
999 		kfree(ee->user_bo);
1000 
1001 		i915_error_object_free(ee->batchbuffer);
1002 		i915_error_object_free(ee->wa_batchbuffer);
1003 		i915_error_object_free(ee->ringbuffer);
1004 		i915_error_object_free(ee->hws_page);
1005 		i915_error_object_free(ee->ctx);
1006 		i915_error_object_free(ee->wa_ctx);
1007 
1008 		kfree(ee->requests);
1009 		if (!IS_ERR_OR_NULL(ee->waiters))
1010 			kfree(ee->waiters);
1011 	}
1012 
1013 	for (i = 0; i < ARRAY_SIZE(error->active_bo); i++)
1014 		kfree(error->active_bo[i]);
1015 	kfree(error->pinned_bo);
1016 
1017 	kfree(error->overlay);
1018 	kfree(error->display);
1019 
1020 	cleanup_params(error);
1021 	cleanup_uc_state(error);
1022 
1023 	err_free_sgl(error->sgl);
1024 	kfree(error);
1025 }
1026 
1027 static struct drm_i915_error_object *
1028 i915_error_object_create(struct drm_i915_private *i915,
1029 			 struct i915_vma *vma)
1030 {
1031 	struct i915_ggtt *ggtt = &i915->ggtt;
1032 	const u64 slot = ggtt->error_capture.start;
1033 	struct drm_i915_error_object *dst;
1034 	struct compress compress;
1035 	unsigned long num_pages;
1036 	struct sgt_iter iter;
1037 	dma_addr_t dma;
1038 	int ret;
1039 
1040 	if (!vma)
1041 		return NULL;
1042 
1043 	num_pages = min_t(u64, vma->size, vma->obj->base.size) >> PAGE_SHIFT;
1044 	num_pages = DIV_ROUND_UP(10 * num_pages, 8); /* worstcase zlib growth */
1045 	dst = kmalloc(sizeof(*dst) + num_pages * sizeof(u32 *),
1046 		      GFP_ATOMIC | __GFP_NOWARN);
1047 	if (!dst)
1048 		return NULL;
1049 
1050 	dst->gtt_offset = vma->node.start;
1051 	dst->gtt_size = vma->node.size;
1052 	dst->num_pages = num_pages;
1053 	dst->page_count = 0;
1054 	dst->unused = 0;
1055 
1056 	if (!compress_init(&compress)) {
1057 		kfree(dst);
1058 		return NULL;
1059 	}
1060 
1061 	ret = -EINVAL;
1062 	for_each_sgt_dma(dma, iter, vma->pages) {
1063 		void __iomem *s;
1064 
1065 		ggtt->vm.insert_page(&ggtt->vm, dma, slot, I915_CACHE_NONE, 0);
1066 
1067 		s = io_mapping_map_atomic_wc(&ggtt->iomap, slot);
1068 		ret = compress_page(&compress, (void  __force *)s, dst);
1069 		io_mapping_unmap_atomic(s);
1070 		if (ret)
1071 			break;
1072 	}
1073 
1074 	if (ret || compress_flush(&compress, dst)) {
1075 		while (dst->page_count--)
1076 			free_page((unsigned long)dst->pages[dst->page_count]);
1077 		kfree(dst);
1078 		dst = NULL;
1079 	}
1080 
1081 	compress_fini(&compress, dst);
1082 	return dst;
1083 }
1084 
1085 /* The error capture is special as tries to run underneath the normal
1086  * locking rules - so we use the raw version of the i915_gem_active lookup.
1087  */
1088 static inline uint32_t
1089 __active_get_seqno(struct i915_gem_active *active)
1090 {
1091 	struct i915_request *request;
1092 
1093 	request = __i915_gem_active_peek(active);
1094 	return request ? request->global_seqno : 0;
1095 }
1096 
1097 static inline int
1098 __active_get_engine_id(struct i915_gem_active *active)
1099 {
1100 	struct i915_request *request;
1101 
1102 	request = __i915_gem_active_peek(active);
1103 	return request ? request->engine->id : -1;
1104 }
1105 
1106 static void capture_bo(struct drm_i915_error_buffer *err,
1107 		       struct i915_vma *vma)
1108 {
1109 	struct drm_i915_gem_object *obj = vma->obj;
1110 
1111 	err->size = obj->base.size;
1112 	err->name = obj->base.name;
1113 
1114 	err->wseqno = __active_get_seqno(&obj->frontbuffer_write);
1115 	err->engine = __active_get_engine_id(&obj->frontbuffer_write);
1116 
1117 	err->gtt_offset = vma->node.start;
1118 	err->read_domains = obj->read_domains;
1119 	err->write_domain = obj->write_domain;
1120 	err->fence_reg = vma->fence ? vma->fence->id : -1;
1121 	err->tiling = i915_gem_object_get_tiling(obj);
1122 	err->dirty = obj->mm.dirty;
1123 	err->purgeable = obj->mm.madv != I915_MADV_WILLNEED;
1124 	err->userptr = obj->userptr.mm != NULL;
1125 	err->cache_level = obj->cache_level;
1126 }
1127 
1128 static u32 capture_error_bo(struct drm_i915_error_buffer *err,
1129 			    int count, struct list_head *head,
1130 			    bool pinned_only)
1131 {
1132 	struct i915_vma *vma;
1133 	int i = 0;
1134 
1135 	list_for_each_entry(vma, head, vm_link) {
1136 		if (!vma->obj)
1137 			continue;
1138 
1139 		if (pinned_only && !i915_vma_is_pinned(vma))
1140 			continue;
1141 
1142 		capture_bo(err++, vma);
1143 		if (++i == count)
1144 			break;
1145 	}
1146 
1147 	return i;
1148 }
1149 
1150 /* Generate a semi-unique error code. The code is not meant to have meaning, The
1151  * code's only purpose is to try to prevent false duplicated bug reports by
1152  * grossly estimating a GPU error state.
1153  *
1154  * TODO Ideally, hashing the batchbuffer would be a very nice way to determine
1155  * the hang if we could strip the GTT offset information from it.
1156  *
1157  * It's only a small step better than a random number in its current form.
1158  */
1159 static uint32_t i915_error_generate_code(struct drm_i915_private *dev_priv,
1160 					 struct i915_gpu_state *error,
1161 					 int *engine_id)
1162 {
1163 	uint32_t error_code = 0;
1164 	int i;
1165 
1166 	/* IPEHR would be an ideal way to detect errors, as it's the gross
1167 	 * measure of "the command that hung." However, has some very common
1168 	 * synchronization commands which almost always appear in the case
1169 	 * strictly a client bug. Use instdone to differentiate those some.
1170 	 */
1171 	for (i = 0; i < I915_NUM_ENGINES; i++) {
1172 		if (error->engine[i].hangcheck_stalled) {
1173 			if (engine_id)
1174 				*engine_id = i;
1175 
1176 			return error->engine[i].ipehr ^
1177 			       error->engine[i].instdone.instdone;
1178 		}
1179 	}
1180 
1181 	return error_code;
1182 }
1183 
1184 static void gem_record_fences(struct i915_gpu_state *error)
1185 {
1186 	struct drm_i915_private *dev_priv = error->i915;
1187 	int i;
1188 
1189 	if (INTEL_GEN(dev_priv) >= 6) {
1190 		for (i = 0; i < dev_priv->num_fence_regs; i++)
1191 			error->fence[i] = I915_READ64(FENCE_REG_GEN6_LO(i));
1192 	} else if (INTEL_GEN(dev_priv) >= 4) {
1193 		for (i = 0; i < dev_priv->num_fence_regs; i++)
1194 			error->fence[i] = I915_READ64(FENCE_REG_965_LO(i));
1195 	} else {
1196 		for (i = 0; i < dev_priv->num_fence_regs; i++)
1197 			error->fence[i] = I915_READ(FENCE_REG(i));
1198 	}
1199 	error->nfence = i;
1200 }
1201 
1202 static void gen6_record_semaphore_state(struct intel_engine_cs *engine,
1203 					struct drm_i915_error_engine *ee)
1204 {
1205 	struct drm_i915_private *dev_priv = engine->i915;
1206 
1207 	ee->semaphore_mboxes[0] = I915_READ(RING_SYNC_0(engine->mmio_base));
1208 	ee->semaphore_mboxes[1] = I915_READ(RING_SYNC_1(engine->mmio_base));
1209 	if (HAS_VEBOX(dev_priv))
1210 		ee->semaphore_mboxes[2] =
1211 			I915_READ(RING_SYNC_2(engine->mmio_base));
1212 }
1213 
1214 static void error_record_engine_waiters(struct intel_engine_cs *engine,
1215 					struct drm_i915_error_engine *ee)
1216 {
1217 	struct intel_breadcrumbs *b = &engine->breadcrumbs;
1218 	struct drm_i915_error_waiter *waiter;
1219 	struct rb_node *rb;
1220 	int count;
1221 
1222 	ee->num_waiters = 0;
1223 	ee->waiters = NULL;
1224 
1225 	if (RB_EMPTY_ROOT(&b->waiters))
1226 		return;
1227 
1228 	if (!spin_trylock_irq(&b->rb_lock)) {
1229 		ee->waiters = ERR_PTR(-EDEADLK);
1230 		return;
1231 	}
1232 
1233 	count = 0;
1234 	for (rb = rb_first(&b->waiters); rb != NULL; rb = rb_next(rb))
1235 		count++;
1236 	spin_unlock_irq(&b->rb_lock);
1237 
1238 	waiter = NULL;
1239 	if (count)
1240 		waiter = kmalloc_array(count,
1241 				       sizeof(struct drm_i915_error_waiter),
1242 				       GFP_ATOMIC);
1243 	if (!waiter)
1244 		return;
1245 
1246 	if (!spin_trylock_irq(&b->rb_lock)) {
1247 		kfree(waiter);
1248 		ee->waiters = ERR_PTR(-EDEADLK);
1249 		return;
1250 	}
1251 
1252 	ee->waiters = waiter;
1253 	for (rb = rb_first(&b->waiters); rb; rb = rb_next(rb)) {
1254 		struct intel_wait *w = rb_entry(rb, typeof(*w), node);
1255 
1256 		strcpy(waiter->comm, w->tsk->comm);
1257 		waiter->pid = w->tsk->pid;
1258 		waiter->seqno = w->seqno;
1259 		waiter++;
1260 
1261 		if (++ee->num_waiters == count)
1262 			break;
1263 	}
1264 	spin_unlock_irq(&b->rb_lock);
1265 }
1266 
1267 static void error_record_engine_registers(struct i915_gpu_state *error,
1268 					  struct intel_engine_cs *engine,
1269 					  struct drm_i915_error_engine *ee)
1270 {
1271 	struct drm_i915_private *dev_priv = engine->i915;
1272 
1273 	if (INTEL_GEN(dev_priv) >= 6) {
1274 		ee->rc_psmi = I915_READ(RING_PSMI_CTL(engine->mmio_base));
1275 		if (INTEL_GEN(dev_priv) >= 8) {
1276 			ee->fault_reg = I915_READ(GEN8_RING_FAULT_REG);
1277 		} else {
1278 			gen6_record_semaphore_state(engine, ee);
1279 			ee->fault_reg = I915_READ(RING_FAULT_REG(engine));
1280 		}
1281 	}
1282 
1283 	if (INTEL_GEN(dev_priv) >= 4) {
1284 		ee->faddr = I915_READ(RING_DMA_FADD(engine->mmio_base));
1285 		ee->ipeir = I915_READ(RING_IPEIR(engine->mmio_base));
1286 		ee->ipehr = I915_READ(RING_IPEHR(engine->mmio_base));
1287 		ee->instps = I915_READ(RING_INSTPS(engine->mmio_base));
1288 		ee->bbaddr = I915_READ(RING_BBADDR(engine->mmio_base));
1289 		if (INTEL_GEN(dev_priv) >= 8) {
1290 			ee->faddr |= (u64) I915_READ(RING_DMA_FADD_UDW(engine->mmio_base)) << 32;
1291 			ee->bbaddr |= (u64) I915_READ(RING_BBADDR_UDW(engine->mmio_base)) << 32;
1292 		}
1293 		ee->bbstate = I915_READ(RING_BBSTATE(engine->mmio_base));
1294 	} else {
1295 		ee->faddr = I915_READ(DMA_FADD_I8XX);
1296 		ee->ipeir = I915_READ(IPEIR);
1297 		ee->ipehr = I915_READ(IPEHR);
1298 	}
1299 
1300 	intel_engine_get_instdone(engine, &ee->instdone);
1301 
1302 	ee->waiting = intel_engine_has_waiter(engine);
1303 	ee->instpm = I915_READ(RING_INSTPM(engine->mmio_base));
1304 	ee->acthd = intel_engine_get_active_head(engine);
1305 	ee->seqno = intel_engine_get_seqno(engine);
1306 	ee->last_seqno = intel_engine_last_submit(engine);
1307 	ee->start = I915_READ_START(engine);
1308 	ee->head = I915_READ_HEAD(engine);
1309 	ee->tail = I915_READ_TAIL(engine);
1310 	ee->ctl = I915_READ_CTL(engine);
1311 	if (INTEL_GEN(dev_priv) > 2)
1312 		ee->mode = I915_READ_MODE(engine);
1313 
1314 	if (!HWS_NEEDS_PHYSICAL(dev_priv)) {
1315 		i915_reg_t mmio;
1316 
1317 		if (IS_GEN7(dev_priv)) {
1318 			switch (engine->id) {
1319 			default:
1320 			case RCS:
1321 				mmio = RENDER_HWS_PGA_GEN7;
1322 				break;
1323 			case BCS:
1324 				mmio = BLT_HWS_PGA_GEN7;
1325 				break;
1326 			case VCS:
1327 				mmio = BSD_HWS_PGA_GEN7;
1328 				break;
1329 			case VECS:
1330 				mmio = VEBOX_HWS_PGA_GEN7;
1331 				break;
1332 			}
1333 		} else if (IS_GEN6(engine->i915)) {
1334 			mmio = RING_HWS_PGA_GEN6(engine->mmio_base);
1335 		} else {
1336 			/* XXX: gen8 returns to sanity */
1337 			mmio = RING_HWS_PGA(engine->mmio_base);
1338 		}
1339 
1340 		ee->hws = I915_READ(mmio);
1341 	}
1342 
1343 	ee->idle = intel_engine_is_idle(engine);
1344 	ee->hangcheck_timestamp = engine->hangcheck.action_timestamp;
1345 	ee->hangcheck_action = engine->hangcheck.action;
1346 	ee->hangcheck_stalled = engine->hangcheck.stalled;
1347 	ee->reset_count = i915_reset_engine_count(&dev_priv->gpu_error,
1348 						  engine);
1349 
1350 	if (HAS_PPGTT(dev_priv)) {
1351 		int i;
1352 
1353 		ee->vm_info.gfx_mode = I915_READ(RING_MODE_GEN7(engine));
1354 
1355 		if (IS_GEN6(dev_priv))
1356 			ee->vm_info.pp_dir_base =
1357 				I915_READ(RING_PP_DIR_BASE_READ(engine));
1358 		else if (IS_GEN7(dev_priv))
1359 			ee->vm_info.pp_dir_base =
1360 				I915_READ(RING_PP_DIR_BASE(engine));
1361 		else if (INTEL_GEN(dev_priv) >= 8)
1362 			for (i = 0; i < 4; i++) {
1363 				ee->vm_info.pdp[i] =
1364 					I915_READ(GEN8_RING_PDP_UDW(engine, i));
1365 				ee->vm_info.pdp[i] <<= 32;
1366 				ee->vm_info.pdp[i] |=
1367 					I915_READ(GEN8_RING_PDP_LDW(engine, i));
1368 			}
1369 	}
1370 }
1371 
1372 static void record_request(struct i915_request *request,
1373 			   struct drm_i915_error_request *erq)
1374 {
1375 	struct i915_gem_context *ctx = request->gem_context;
1376 
1377 	erq->context = ctx->hw_id;
1378 	erq->sched_attr = request->sched.attr;
1379 	erq->ban_score = atomic_read(&ctx->ban_score);
1380 	erq->seqno = request->global_seqno;
1381 	erq->jiffies = request->emitted_jiffies;
1382 	erq->start = i915_ggtt_offset(request->ring->vma);
1383 	erq->head = request->head;
1384 	erq->tail = request->tail;
1385 
1386 	rcu_read_lock();
1387 	erq->pid = ctx->pid ? pid_nr(ctx->pid) : 0;
1388 	rcu_read_unlock();
1389 }
1390 
1391 static void engine_record_requests(struct intel_engine_cs *engine,
1392 				   struct i915_request *first,
1393 				   struct drm_i915_error_engine *ee)
1394 {
1395 	struct i915_request *request;
1396 	int count;
1397 
1398 	count = 0;
1399 	request = first;
1400 	list_for_each_entry_from(request, &engine->timeline.requests, link)
1401 		count++;
1402 	if (!count)
1403 		return;
1404 
1405 	ee->requests = kcalloc(count, sizeof(*ee->requests), GFP_ATOMIC);
1406 	if (!ee->requests)
1407 		return;
1408 
1409 	ee->num_requests = count;
1410 
1411 	count = 0;
1412 	request = first;
1413 	list_for_each_entry_from(request, &engine->timeline.requests, link) {
1414 		if (count >= ee->num_requests) {
1415 			/*
1416 			 * If the ring request list was changed in
1417 			 * between the point where the error request
1418 			 * list was created and dimensioned and this
1419 			 * point then just exit early to avoid crashes.
1420 			 *
1421 			 * We don't need to communicate that the
1422 			 * request list changed state during error
1423 			 * state capture and that the error state is
1424 			 * slightly incorrect as a consequence since we
1425 			 * are typically only interested in the request
1426 			 * list state at the point of error state
1427 			 * capture, not in any changes happening during
1428 			 * the capture.
1429 			 */
1430 			break;
1431 		}
1432 
1433 		record_request(request, &ee->requests[count++]);
1434 	}
1435 	ee->num_requests = count;
1436 }
1437 
1438 static void error_record_engine_execlists(struct intel_engine_cs *engine,
1439 					  struct drm_i915_error_engine *ee)
1440 {
1441 	const struct intel_engine_execlists * const execlists = &engine->execlists;
1442 	unsigned int n;
1443 
1444 	for (n = 0; n < execlists_num_ports(execlists); n++) {
1445 		struct i915_request *rq = port_request(&execlists->port[n]);
1446 
1447 		if (!rq)
1448 			break;
1449 
1450 		record_request(rq, &ee->execlist[n]);
1451 	}
1452 
1453 	ee->num_ports = n;
1454 }
1455 
1456 static void record_context(struct drm_i915_error_context *e,
1457 			   struct i915_gem_context *ctx)
1458 {
1459 	if (ctx->pid) {
1460 		struct task_struct *task;
1461 
1462 		rcu_read_lock();
1463 		task = pid_task(ctx->pid, PIDTYPE_PID);
1464 		if (task) {
1465 			strcpy(e->comm, task->comm);
1466 			e->pid = task->pid;
1467 		}
1468 		rcu_read_unlock();
1469 	}
1470 
1471 	e->handle = ctx->user_handle;
1472 	e->hw_id = ctx->hw_id;
1473 	e->sched_attr = ctx->sched;
1474 	e->ban_score = atomic_read(&ctx->ban_score);
1475 	e->bannable = i915_gem_context_is_bannable(ctx);
1476 	e->guilty = atomic_read(&ctx->guilty_count);
1477 	e->active = atomic_read(&ctx->active_count);
1478 }
1479 
1480 static void request_record_user_bo(struct i915_request *request,
1481 				   struct drm_i915_error_engine *ee)
1482 {
1483 	struct i915_capture_list *c;
1484 	struct drm_i915_error_object **bo;
1485 	long count, max;
1486 
1487 	max = 0;
1488 	for (c = request->capture_list; c; c = c->next)
1489 		max++;
1490 	if (!max)
1491 		return;
1492 
1493 	bo = kmalloc_array(max, sizeof(*bo), GFP_ATOMIC);
1494 	if (!bo) {
1495 		/* If we can't capture everything, try to capture something. */
1496 		max = min_t(long, max, PAGE_SIZE / sizeof(*bo));
1497 		bo = kmalloc_array(max, sizeof(*bo), GFP_ATOMIC);
1498 	}
1499 	if (!bo)
1500 		return;
1501 
1502 	count = 0;
1503 	for (c = request->capture_list; c; c = c->next) {
1504 		bo[count] = i915_error_object_create(request->i915, c->vma);
1505 		if (!bo[count])
1506 			break;
1507 		if (++count == max)
1508 			break;
1509 	}
1510 
1511 	ee->user_bo = bo;
1512 	ee->user_bo_count = count;
1513 }
1514 
1515 static struct drm_i915_error_object *
1516 capture_object(struct drm_i915_private *dev_priv,
1517 	       struct drm_i915_gem_object *obj)
1518 {
1519 	if (obj && i915_gem_object_has_pages(obj)) {
1520 		struct i915_vma fake = {
1521 			.node = { .start = U64_MAX, .size = obj->base.size },
1522 			.size = obj->base.size,
1523 			.pages = obj->mm.pages,
1524 			.obj = obj,
1525 		};
1526 
1527 		return i915_error_object_create(dev_priv, &fake);
1528 	} else {
1529 		return NULL;
1530 	}
1531 }
1532 
1533 static void gem_record_rings(struct i915_gpu_state *error)
1534 {
1535 	struct drm_i915_private *i915 = error->i915;
1536 	struct i915_ggtt *ggtt = &i915->ggtt;
1537 	int i;
1538 
1539 	for (i = 0; i < I915_NUM_ENGINES; i++) {
1540 		struct intel_engine_cs *engine = i915->engine[i];
1541 		struct drm_i915_error_engine *ee = &error->engine[i];
1542 		struct i915_request *request;
1543 
1544 		ee->engine_id = -1;
1545 
1546 		if (!engine)
1547 			continue;
1548 
1549 		ee->engine_id = i;
1550 
1551 		error_record_engine_registers(error, engine, ee);
1552 		error_record_engine_waiters(engine, ee);
1553 		error_record_engine_execlists(engine, ee);
1554 
1555 		request = i915_gem_find_active_request(engine);
1556 		if (request) {
1557 			struct i915_gem_context *ctx = request->gem_context;
1558 			struct intel_ring *ring;
1559 
1560 			ee->vm = ctx->ppgtt ? &ctx->ppgtt->vm : &ggtt->vm;
1561 
1562 			record_context(&ee->context, ctx);
1563 
1564 			/* We need to copy these to an anonymous buffer
1565 			 * as the simplest method to avoid being overwritten
1566 			 * by userspace.
1567 			 */
1568 			ee->batchbuffer =
1569 				i915_error_object_create(i915, request->batch);
1570 
1571 			if (HAS_BROKEN_CS_TLB(i915))
1572 				ee->wa_batchbuffer =
1573 					i915_error_object_create(i915,
1574 								 i915->gt.scratch);
1575 			request_record_user_bo(request, ee);
1576 
1577 			ee->ctx =
1578 				i915_error_object_create(i915,
1579 							 request->hw_context->state);
1580 
1581 			error->simulated |=
1582 				i915_gem_context_no_error_capture(ctx);
1583 
1584 			ee->rq_head = request->head;
1585 			ee->rq_post = request->postfix;
1586 			ee->rq_tail = request->tail;
1587 
1588 			ring = request->ring;
1589 			ee->cpu_ring_head = ring->head;
1590 			ee->cpu_ring_tail = ring->tail;
1591 			ee->ringbuffer =
1592 				i915_error_object_create(i915, ring->vma);
1593 
1594 			engine_record_requests(engine, request, ee);
1595 		}
1596 
1597 		ee->hws_page =
1598 			i915_error_object_create(i915,
1599 						 engine->status_page.vma);
1600 
1601 		ee->wa_ctx = i915_error_object_create(i915, engine->wa_ctx.vma);
1602 
1603 		ee->default_state = capture_object(i915, engine->default_state);
1604 	}
1605 }
1606 
1607 static void gem_capture_vm(struct i915_gpu_state *error,
1608 			   struct i915_address_space *vm,
1609 			   int idx)
1610 {
1611 	struct drm_i915_error_buffer *active_bo;
1612 	struct i915_vma *vma;
1613 	int count;
1614 
1615 	count = 0;
1616 	list_for_each_entry(vma, &vm->active_list, vm_link)
1617 		count++;
1618 
1619 	active_bo = NULL;
1620 	if (count)
1621 		active_bo = kcalloc(count, sizeof(*active_bo), GFP_ATOMIC);
1622 	if (active_bo)
1623 		count = capture_error_bo(active_bo, count, &vm->active_list, false);
1624 	else
1625 		count = 0;
1626 
1627 	error->active_vm[idx] = vm;
1628 	error->active_bo[idx] = active_bo;
1629 	error->active_bo_count[idx] = count;
1630 }
1631 
1632 static void capture_active_buffers(struct i915_gpu_state *error)
1633 {
1634 	int cnt = 0, i, j;
1635 
1636 	BUILD_BUG_ON(ARRAY_SIZE(error->engine) > ARRAY_SIZE(error->active_bo));
1637 	BUILD_BUG_ON(ARRAY_SIZE(error->active_bo) != ARRAY_SIZE(error->active_vm));
1638 	BUILD_BUG_ON(ARRAY_SIZE(error->active_bo) != ARRAY_SIZE(error->active_bo_count));
1639 
1640 	/* Scan each engine looking for unique active contexts/vm */
1641 	for (i = 0; i < ARRAY_SIZE(error->engine); i++) {
1642 		struct drm_i915_error_engine *ee = &error->engine[i];
1643 		bool found;
1644 
1645 		if (!ee->vm)
1646 			continue;
1647 
1648 		found = false;
1649 		for (j = 0; j < i && !found; j++)
1650 			found = error->engine[j].vm == ee->vm;
1651 		if (!found)
1652 			gem_capture_vm(error, ee->vm, cnt++);
1653 	}
1654 }
1655 
1656 static void capture_pinned_buffers(struct i915_gpu_state *error)
1657 {
1658 	struct i915_address_space *vm = &error->i915->ggtt.vm;
1659 	struct drm_i915_error_buffer *bo;
1660 	struct i915_vma *vma;
1661 	int count_inactive, count_active;
1662 
1663 	count_inactive = 0;
1664 	list_for_each_entry(vma, &vm->inactive_list, vm_link)
1665 		count_inactive++;
1666 
1667 	count_active = 0;
1668 	list_for_each_entry(vma, &vm->active_list, vm_link)
1669 		count_active++;
1670 
1671 	bo = NULL;
1672 	if (count_inactive + count_active)
1673 		bo = kcalloc(count_inactive + count_active,
1674 			     sizeof(*bo), GFP_ATOMIC);
1675 	if (!bo)
1676 		return;
1677 
1678 	count_inactive = capture_error_bo(bo, count_inactive,
1679 					  &vm->active_list, true);
1680 	count_active = capture_error_bo(bo + count_inactive, count_active,
1681 					&vm->inactive_list, true);
1682 	error->pinned_bo_count = count_inactive + count_active;
1683 	error->pinned_bo = bo;
1684 }
1685 
1686 static void capture_uc_state(struct i915_gpu_state *error)
1687 {
1688 	struct drm_i915_private *i915 = error->i915;
1689 	struct i915_error_uc *error_uc = &error->uc;
1690 
1691 	/* Capturing uC state won't be useful if there is no GuC */
1692 	if (!error->device_info.has_guc)
1693 		return;
1694 
1695 	error_uc->guc_fw = i915->guc.fw;
1696 	error_uc->huc_fw = i915->huc.fw;
1697 
1698 	/* Non-default firmware paths will be specified by the modparam.
1699 	 * As modparams are generally accesible from the userspace make
1700 	 * explicit copies of the firmware paths.
1701 	 */
1702 	error_uc->guc_fw.path = kstrdup(i915->guc.fw.path, GFP_ATOMIC);
1703 	error_uc->huc_fw.path = kstrdup(i915->huc.fw.path, GFP_ATOMIC);
1704 	error_uc->guc_log = i915_error_object_create(i915, i915->guc.log.vma);
1705 }
1706 
1707 /* Capture all registers which don't fit into another category. */
1708 static void capture_reg_state(struct i915_gpu_state *error)
1709 {
1710 	struct drm_i915_private *dev_priv = error->i915;
1711 	int i;
1712 
1713 	/* General organization
1714 	 * 1. Registers specific to a single generation
1715 	 * 2. Registers which belong to multiple generations
1716 	 * 3. Feature specific registers.
1717 	 * 4. Everything else
1718 	 * Please try to follow the order.
1719 	 */
1720 
1721 	/* 1: Registers specific to a single generation */
1722 	if (IS_VALLEYVIEW(dev_priv)) {
1723 		error->gtier[0] = I915_READ(GTIER);
1724 		error->ier = I915_READ(VLV_IER);
1725 		error->forcewake = I915_READ_FW(FORCEWAKE_VLV);
1726 	}
1727 
1728 	if (IS_GEN7(dev_priv))
1729 		error->err_int = I915_READ(GEN7_ERR_INT);
1730 
1731 	if (INTEL_GEN(dev_priv) >= 8) {
1732 		error->fault_data0 = I915_READ(GEN8_FAULT_TLB_DATA0);
1733 		error->fault_data1 = I915_READ(GEN8_FAULT_TLB_DATA1);
1734 	}
1735 
1736 	if (IS_GEN6(dev_priv)) {
1737 		error->forcewake = I915_READ_FW(FORCEWAKE);
1738 		error->gab_ctl = I915_READ(GAB_CTL);
1739 		error->gfx_mode = I915_READ(GFX_MODE);
1740 	}
1741 
1742 	/* 2: Registers which belong to multiple generations */
1743 	if (INTEL_GEN(dev_priv) >= 7)
1744 		error->forcewake = I915_READ_FW(FORCEWAKE_MT);
1745 
1746 	if (INTEL_GEN(dev_priv) >= 6) {
1747 		error->derrmr = I915_READ(DERRMR);
1748 		error->error = I915_READ(ERROR_GEN6);
1749 		error->done_reg = I915_READ(DONE_REG);
1750 	}
1751 
1752 	if (INTEL_GEN(dev_priv) >= 5)
1753 		error->ccid = I915_READ(CCID);
1754 
1755 	/* 3: Feature specific registers */
1756 	if (IS_GEN6(dev_priv) || IS_GEN7(dev_priv)) {
1757 		error->gam_ecochk = I915_READ(GAM_ECOCHK);
1758 		error->gac_eco = I915_READ(GAC_ECO_BITS);
1759 	}
1760 
1761 	/* 4: Everything else */
1762 	if (INTEL_GEN(dev_priv) >= 11) {
1763 		error->ier = I915_READ(GEN8_DE_MISC_IER);
1764 		error->gtier[0] = I915_READ(GEN11_RENDER_COPY_INTR_ENABLE);
1765 		error->gtier[1] = I915_READ(GEN11_VCS_VECS_INTR_ENABLE);
1766 		error->gtier[2] = I915_READ(GEN11_GUC_SG_INTR_ENABLE);
1767 		error->gtier[3] = I915_READ(GEN11_GPM_WGBOXPERF_INTR_ENABLE);
1768 		error->gtier[4] = I915_READ(GEN11_CRYPTO_RSVD_INTR_ENABLE);
1769 		error->gtier[5] = I915_READ(GEN11_GUNIT_CSME_INTR_ENABLE);
1770 		error->ngtier = 6;
1771 	} else if (INTEL_GEN(dev_priv) >= 8) {
1772 		error->ier = I915_READ(GEN8_DE_MISC_IER);
1773 		for (i = 0; i < 4; i++)
1774 			error->gtier[i] = I915_READ(GEN8_GT_IER(i));
1775 		error->ngtier = 4;
1776 	} else if (HAS_PCH_SPLIT(dev_priv)) {
1777 		error->ier = I915_READ(DEIER);
1778 		error->gtier[0] = I915_READ(GTIER);
1779 		error->ngtier = 1;
1780 	} else if (IS_GEN2(dev_priv)) {
1781 		error->ier = I915_READ16(IER);
1782 	} else if (!IS_VALLEYVIEW(dev_priv)) {
1783 		error->ier = I915_READ(IER);
1784 	}
1785 	error->eir = I915_READ(EIR);
1786 	error->pgtbl_er = I915_READ(PGTBL_ER);
1787 }
1788 
1789 static void i915_error_capture_msg(struct drm_i915_private *dev_priv,
1790 				   struct i915_gpu_state *error,
1791 				   u32 engine_mask,
1792 				   const char *error_msg)
1793 {
1794 	u32 ecode;
1795 	int engine_id = -1, len;
1796 
1797 	ecode = i915_error_generate_code(dev_priv, error, &engine_id);
1798 
1799 	len = scnprintf(error->error_msg, sizeof(error->error_msg),
1800 			"GPU HANG: ecode %d:%d:0x%08x",
1801 			INTEL_GEN(dev_priv), engine_id, ecode);
1802 
1803 	if (engine_id != -1 && error->engine[engine_id].context.pid)
1804 		len += scnprintf(error->error_msg + len,
1805 				 sizeof(error->error_msg) - len,
1806 				 ", in %s [%d]",
1807 				 error->engine[engine_id].context.comm,
1808 				 error->engine[engine_id].context.pid);
1809 
1810 	scnprintf(error->error_msg + len, sizeof(error->error_msg) - len,
1811 		  ", reason: %s, action: %s",
1812 		  error_msg,
1813 		  engine_mask ? "reset" : "continue");
1814 }
1815 
1816 static void capture_gen_state(struct i915_gpu_state *error)
1817 {
1818 	struct drm_i915_private *i915 = error->i915;
1819 
1820 	error->awake = i915->gt.awake;
1821 	error->wakelock = atomic_read(&i915->runtime_pm.wakeref_count);
1822 	error->suspended = i915->runtime_pm.suspended;
1823 
1824 	error->iommu = -1;
1825 #ifdef CONFIG_INTEL_IOMMU
1826 	error->iommu = intel_iommu_gfx_mapped;
1827 #endif
1828 	error->reset_count = i915_reset_count(&i915->gpu_error);
1829 	error->suspend_count = i915->suspend_count;
1830 
1831 	memcpy(&error->device_info,
1832 	       INTEL_INFO(i915),
1833 	       sizeof(error->device_info));
1834 	error->driver_caps = i915->caps;
1835 }
1836 
1837 static __always_inline void dup_param(const char *type, void *x)
1838 {
1839 	if (!__builtin_strcmp(type, "char *"))
1840 		*(void **)x = kstrdup(*(void **)x, GFP_ATOMIC);
1841 }
1842 
1843 static void capture_params(struct i915_gpu_state *error)
1844 {
1845 	error->params = i915_modparams;
1846 #define DUP(T, x, ...) dup_param(#T, &error->params.x);
1847 	I915_PARAMS_FOR_EACH(DUP);
1848 #undef DUP
1849 }
1850 
1851 static unsigned long capture_find_epoch(const struct i915_gpu_state *error)
1852 {
1853 	unsigned long epoch = error->capture;
1854 	int i;
1855 
1856 	for (i = 0; i < ARRAY_SIZE(error->engine); i++) {
1857 		const struct drm_i915_error_engine *ee = &error->engine[i];
1858 
1859 		if (ee->hangcheck_stalled &&
1860 		    time_before(ee->hangcheck_timestamp, epoch))
1861 			epoch = ee->hangcheck_timestamp;
1862 	}
1863 
1864 	return epoch;
1865 }
1866 
1867 static void capture_finish(struct i915_gpu_state *error)
1868 {
1869 	struct i915_ggtt *ggtt = &error->i915->ggtt;
1870 	const u64 slot = ggtt->error_capture.start;
1871 
1872 	ggtt->vm.clear_range(&ggtt->vm, slot, PAGE_SIZE);
1873 }
1874 
1875 static int capture(void *data)
1876 {
1877 	struct i915_gpu_state *error = data;
1878 
1879 	error->time = ktime_get_real();
1880 	error->boottime = ktime_get_boottime();
1881 	error->uptime = ktime_sub(ktime_get(),
1882 				  error->i915->gt.last_init_time);
1883 	error->capture = jiffies;
1884 
1885 	capture_params(error);
1886 	capture_gen_state(error);
1887 	capture_uc_state(error);
1888 	capture_reg_state(error);
1889 	gem_record_fences(error);
1890 	gem_record_rings(error);
1891 	capture_active_buffers(error);
1892 	capture_pinned_buffers(error);
1893 
1894 	error->overlay = intel_overlay_capture_error_state(error->i915);
1895 	error->display = intel_display_capture_error_state(error->i915);
1896 
1897 	error->epoch = capture_find_epoch(error);
1898 
1899 	capture_finish(error);
1900 	return 0;
1901 }
1902 
1903 #define DAY_AS_SECONDS(x) (24 * 60 * 60 * (x))
1904 
1905 struct i915_gpu_state *
1906 i915_capture_gpu_state(struct drm_i915_private *i915)
1907 {
1908 	struct i915_gpu_state *error;
1909 
1910 	error = kzalloc(sizeof(*error), GFP_ATOMIC);
1911 	if (!error)
1912 		return NULL;
1913 
1914 	kref_init(&error->ref);
1915 	error->i915 = i915;
1916 
1917 	stop_machine(capture, error, NULL);
1918 
1919 	return error;
1920 }
1921 
1922 /**
1923  * i915_capture_error_state - capture an error record for later analysis
1924  * @i915: i915 device
1925  * @engine_mask: the mask of engines triggering the hang
1926  * @error_msg: a message to insert into the error capture header
1927  *
1928  * Should be called when an error is detected (either a hang or an error
1929  * interrupt) to capture error state from the time of the error.  Fills
1930  * out a structure which becomes available in debugfs for user level tools
1931  * to pick up.
1932  */
1933 void i915_capture_error_state(struct drm_i915_private *i915,
1934 			      u32 engine_mask,
1935 			      const char *error_msg)
1936 {
1937 	static bool warned;
1938 	struct i915_gpu_state *error;
1939 	unsigned long flags;
1940 
1941 	if (!i915_modparams.error_capture)
1942 		return;
1943 
1944 	if (READ_ONCE(i915->gpu_error.first_error))
1945 		return;
1946 
1947 	error = i915_capture_gpu_state(i915);
1948 	if (!error) {
1949 		DRM_DEBUG_DRIVER("out of memory, not capturing error state\n");
1950 		i915_disable_error_state(i915, -ENOMEM);
1951 		return;
1952 	}
1953 
1954 	i915_error_capture_msg(i915, error, engine_mask, error_msg);
1955 	DRM_INFO("%s\n", error->error_msg);
1956 
1957 	if (!error->simulated) {
1958 		spin_lock_irqsave(&i915->gpu_error.lock, flags);
1959 		if (!i915->gpu_error.first_error) {
1960 			i915->gpu_error.first_error = error;
1961 			error = NULL;
1962 		}
1963 		spin_unlock_irqrestore(&i915->gpu_error.lock, flags);
1964 	}
1965 
1966 	if (error) {
1967 		__i915_gpu_state_free(&error->ref);
1968 		return;
1969 	}
1970 
1971 	if (!warned &&
1972 	    ktime_get_real_seconds() - DRIVER_TIMESTAMP < DAY_AS_SECONDS(180)) {
1973 		DRM_INFO("GPU hangs can indicate a bug anywhere in the entire gfx stack, including userspace.\n");
1974 		DRM_INFO("Please file a _new_ bug report on bugs.freedesktop.org against DRI -> DRM/Intel\n");
1975 		DRM_INFO("drm/i915 developers can then reassign to the right component if it's not a kernel issue.\n");
1976 		DRM_INFO("The gpu crash dump is required to analyze gpu hangs, so please always attach it.\n");
1977 		DRM_INFO("GPU crash dump saved to /sys/class/drm/card%d/error\n",
1978 			 i915->drm.primary->index);
1979 		warned = true;
1980 	}
1981 }
1982 
1983 struct i915_gpu_state *
1984 i915_first_error_state(struct drm_i915_private *i915)
1985 {
1986 	struct i915_gpu_state *error;
1987 
1988 	spin_lock_irq(&i915->gpu_error.lock);
1989 	error = i915->gpu_error.first_error;
1990 	if (error)
1991 		i915_gpu_state_get(error);
1992 	spin_unlock_irq(&i915->gpu_error.lock);
1993 
1994 	return error;
1995 }
1996 
1997 void i915_reset_error_state(struct drm_i915_private *i915)
1998 {
1999 	struct i915_gpu_state *error;
2000 
2001 	spin_lock_irq(&i915->gpu_error.lock);
2002 	error = i915->gpu_error.first_error;
2003 	i915->gpu_error.first_error = NULL;
2004 	spin_unlock_irq(&i915->gpu_error.lock);
2005 
2006 	if (!IS_ERR(error))
2007 		i915_gpu_state_put(error);
2008 }
2009 
2010 void i915_disable_error_state(struct drm_i915_private *i915, int err)
2011 {
2012 	spin_lock_irq(&i915->gpu_error.lock);
2013 	if (!i915->gpu_error.first_error)
2014 		i915->gpu_error.first_error = ERR_PTR(err);
2015 	spin_unlock_irq(&i915->gpu_error.lock);
2016 }
2017