xref: /xnu-12377.61.12/osfmk/arm/model_dep.c (revision 4d495c6e23c53686cf65f45067f79024cf5dcee8)
1 /*
2  * Copyright (c) 2007-2020 Apple Inc. All rights reserved.
3  *
4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5  *
6  * This file contains Original Code and/or Modifications of Original Code
7  * as defined in and that are subject to the Apple Public Source License
8  * Version 2.0 (the 'License'). You may not use this file except in
9  * compliance with the License. The rights granted to you under the License
10  * may not be used to create, or enable the creation or redistribution of,
11  * unlawful or unlicensed copies of an Apple operating system, or to
12  * circumvent, violate, or enable the circumvention or violation of, any
13  * terms of an Apple operating system software license agreement.
14  *
15  * Please obtain a copy of the License at
16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
17  *
18  * The Original Code and all software distributed under the License are
19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23  * Please see the License for the specific language governing rights and
24  * limitations under the License.
25  *
26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27  */
28 
29 #include <debug.h>
30 #include <mach_kdp.h>
31 #include <kern/kern_stackshot.h>
32 
33 #include <kern/thread.h>
34 #include <machine/pmap.h>
35 #include <device/device_types.h>
36 
37 #include <mach/vm_param.h>
38 #include <mach/clock_types.h>
39 #include <mach/machine.h>
40 #include <mach/kmod.h>
41 #include <pexpert/boot.h>
42 #include <pexpert/pexpert.h>
43 
44 #include <ptrauth.h>
45 
46 #include <kern/misc_protos.h>
47 #include <kern/startup.h>
48 #include <kern/clock.h>
49 #include <kern/debug.h>
50 #include <kern/processor.h>
51 #include <kdp/kdp_core.h>
52 #if ALTERNATE_DEBUGGER
53 #include <arm64/alternate_debugger.h>
54 #endif
55 #include <machine/atomic.h>
56 #include <machine/trap.h>
57 #include <kern/spl.h>
58 #include <pexpert/pexpert.h>
59 #include <kdp/kdp_callout.h>
60 #include <kdp/kdp_dyld.h>
61 #include <kdp/kdp_internal.h>
62 #include <kdp/kdp_common.h>
63 #include <uuid/uuid.h>
64 #include <sys/codesign.h>
65 #include <sys/time.h>
66 
67 #if CONFIG_SPTM
68 #include <kern/percpu.h>
69 #include <arm64/sptm/pmap/pmap_data.h>
70 #endif
71 
72 #include <IOKit/IOPlatformExpert.h>
73 #include <IOKit/IOKitServer.h>
74 
75 #include <mach/vm_prot.h>
76 #include <vm/vm_map_xnu.h>
77 #include <vm/pmap.h>
78 #include <vm/vm_shared_region.h>
79 #include <mach/time_value.h>
80 #include <machine/machparam.h>  /* for btop */
81 
82 #include <console/video_console.h>
83 #include <console/serial_protos.h>
84 #include <arm/cpu_data.h>
85 #include <arm/cpu_data_internal.h>
86 #include <arm/cpu_internal.h>
87 #include <arm/misc_protos.h>
88 #include <libkern/OSKextLibPrivate.h>
89 #include <vm/vm_kern.h>
90 #include <kern/kern_cdata.h>
91 #include <kern/ledger.h>
92 #include <san/kcov_ksancov.h>
93 
94 
95 #if DEVELOPMENT || DEBUG
96 #include <kern/ext_paniclog.h>
97 #endif
98 
99 #if CONFIG_EXCLAVES
100 #include <kern/exclaves_panic.h>
101 #include <kern/exclaves_inspection.h>
102 #endif
103 
104 
105 #if     MACH_KDP
106 void    kdp_trap(unsigned int, struct arm_saved_state *);
107 #endif
108 
109 /*
110  * Increment the PANICLOG_VERSION if you change the format of the panic
111  * log in any way.
112  */
113 #define PANICLOG_VERSION 15
114 static struct kcdata_descriptor kc_panic_data;
115 
116 extern char iBoot_version[];
117 #if defined(TARGET_OS_OSX) && defined(__arm64__)
118 extern char iBoot_Stage_2_version[];
119 #endif /* defined(TARGET_OS_OSX) && defined(__arm64__) */
120 
121 extern volatile uint32_t        debug_enabled;
122 extern unsigned int         not_in_kdp;
123 
124 extern int                              copyinframe(vm_address_t fp, uint32_t * frame);
125 extern void                             kdp_callouts(kdp_event_t event);
126 
127 #define MAX_PROCNAME_LEN 32
128 /* #include <sys/proc.h> */
129 struct proc;
130 extern int        proc_pid(struct proc *p);
131 extern void       proc_name_kdp(struct proc *, char *, int);
132 
133 /*
134  * Make sure there's enough space to include the relevant bits in the format required
135  * within the space allocated for the panic version string in the panic header.
136  * The format required by OSAnalytics/DumpPanic is 'Product Version (OS Version)'.
137  */
138 #define PANIC_HEADER_VERSION_FMT_STR "%.14s (%.14s)"
139 
140 extern const char version[];
141 extern char       osversion[];
142 extern char       osproductversion[];
143 extern char       osreleasetype[];
144 
145 #if defined(XNU_TARGET_OS_BRIDGE)
146 extern char     macosproductversion[];
147 extern char     macosversion[];
148 #endif
149 
150 extern uint8_t          gPlatformECID[8];
151 extern uint32_t         gPlatformMemoryID;
152 
153 extern uint64_t         last_hwaccess_thread;
154 extern uint8_t          last_hwaccess_type; /* 0 : read, 1 : write. */
155 extern uint8_t          last_hwaccess_size;
156 extern uint64_t         last_hwaccess_paddr;
157 
158 /*Choosing the size for gTargetTypeBuffer as 16 and size for gModelTypeBuffer as 32
159  *  since the target name and model name typically  doesn't exceed this size */
160 extern char  gTargetTypeBuffer[16];
161 extern char  gModelTypeBuffer[32];
162 
163 extern struct timeval    gIOLastSleepTime;
164 extern struct timeval    gIOLastWakeTime;
165 extern boolean_t                 is_clock_configured;
166 extern boolean_t kernelcache_uuid_valid;
167 extern uuid_t kernelcache_uuid;
168 extern uuid_string_t bootsessionuuid_string;
169 
170 extern uint64_t roots_installed;
171 
172 /* Definitions for frame pointers */
173 #define FP_ALIGNMENT_MASK      ((uint32_t)(0x3))
174 #define FP_LR_OFFSET           ((uint32_t)4)
175 #define FP_LR_OFFSET64         ((uint32_t)8)
176 #define FP_MAX_NUM_TO_EVALUATE (50)
177 
178 /* Timeout for all processors responding to debug crosscall */
179 MACHINE_TIMEOUT_ALWAYS_ENABLED(debug_ack_timeout, "debug-ack", 240000, MACHINE_TIMEOUT_UNIT_TIMEBASE);
180 
181 /* Forward functions definitions */
182 void panic_display_times(void);
183 void panic_print_symbol_name(vm_address_t search);
184 
185 
186 /* Global variables */
187 static uint32_t       panic_bt_depth;
188 boolean_t             PanicInfoSaved = FALSE;
189 boolean_t             force_immediate_debug_halt = FALSE;
190 unsigned int          debug_ack_timeout_count = 0;
191 _Atomic unsigned int  debugger_sync = 0;
192 _Atomic unsigned int  mp_kdp_trap = 0; /* CPUs signalled by the debug CPU will spin on this */
193 _Atomic unsigned int  debug_cpus_spinning = 0; /* Number of signalled CPUs still spinning on mp_kdp_trap (in DebuggerXCall). */
194 unsigned int          DebugContextCount = 0;
195 bool                  trap_is_stackshot = false; /* Whether the trap is for a stackshot */
196 
197 #if defined(__arm64__)
198 uint8_t PE_smc_stashed_x86_system_state = 0xFF;
199 uint8_t PE_smc_stashed_x86_power_state = 0xFF;
200 uint8_t PE_smc_stashed_x86_efi_boot_state = 0xFF;
201 uint8_t PE_smc_stashed_x86_shutdown_cause = 0xFF;
202 uint64_t PE_smc_stashed_x86_prev_power_transitions = UINT64_MAX;
203 uint32_t PE_pcie_stashed_link_state = UINT32_MAX;
204 uint64_t PE_nvram_stashed_x86_macos_slide = UINT64_MAX;
205 #endif
206 
207 
208 static void
do_print_backtrace_internal(pmap_t pmap,vm_offset_t topfp,const char * cur_marker,boolean_t is_64_bit,boolean_t print_kexts_in_backtrace)209 do_print_backtrace_internal(pmap_t pmap, vm_offset_t topfp, const char *cur_marker,
210     boolean_t is_64_bit, boolean_t print_kexts_in_backtrace)
211 {
212 	unsigned int    i = 0;
213 	addr64_t        lr = 0;
214 	addr64_t        fp = topfp;
215 	addr64_t        fp_for_ppn = 0;
216 	ppnum_t         ppn = (ppnum_t)NULL;
217 	vm_offset_t     raddrs[FP_MAX_NUM_TO_EVALUATE] = { 0 };
218 	bool            dump_kernel_stack = (fp >= VM_MIN_KERNEL_ADDRESS);
219 
220 	do {
221 		if ((fp == 0) || ((fp & FP_ALIGNMENT_MASK) != 0)) {
222 			break;
223 		}
224 
225 		if ((!dump_kernel_stack) && (fp >= VM_MIN_KERNEL_ADDRESS)) {
226 			break;
227 		}
228 
229 		/*
230 		 * Check to see if current address will result in a different
231 		 * ppn than previously computed (to avoid recomputation) via
232 		 * (addr) ^ fp_for_ppn) >> PAGE_SHIFT)
233 		 */
234 		if ((((fp + FP_LR_OFFSET) ^ fp_for_ppn) >> PAGE_SHIFT) != 0x0U) {
235 			ppn = pmap_find_phys(pmap, fp + FP_LR_OFFSET);
236 			fp_for_ppn = fp + (is_64_bit ? FP_LR_OFFSET64 : FP_LR_OFFSET);
237 		}
238 		if (ppn != (ppnum_t)NULL) {
239 			if (is_64_bit) {
240 				lr = ml_phys_read_double_64(((((vm_offset_t)ppn) << PAGE_SHIFT)) | ((fp + FP_LR_OFFSET64) & PAGE_MASK));
241 #if defined(HAS_APPLE_PAC)
242 				/* return addresses on stack will be signed by arm64e ABI */
243 				lr = (addr64_t) ptrauth_strip((void *)lr, ptrauth_key_return_address);
244 #endif
245 			} else {
246 				lr = ml_phys_read_word(((((vm_offset_t)ppn) << PAGE_SHIFT)) | ((fp + FP_LR_OFFSET) & PAGE_MASK));
247 			}
248 		} else {
249 			if (is_64_bit) {
250 				paniclog_append_noflush("%s\t  Could not read LR from frame at 0x%016llx\n", cur_marker, fp + FP_LR_OFFSET64);
251 			} else {
252 				paniclog_append_noflush("%s\t  Could not read LR from frame at 0x%08x\n", cur_marker, (uint32_t)(fp + FP_LR_OFFSET));
253 			}
254 			break;
255 		}
256 		if (((fp ^ fp_for_ppn) >> PAGE_SHIFT) != 0x0U) {
257 			ppn = pmap_find_phys(pmap, fp);
258 			fp_for_ppn = fp;
259 		}
260 		if (ppn != (ppnum_t)NULL) {
261 			if (is_64_bit) {
262 				fp = ml_phys_read_double_64(((((vm_offset_t)ppn) << PAGE_SHIFT)) | (fp & PAGE_MASK));
263 #if defined(HAS_APPLE_PAC)
264 				/* frame pointers on stack will be signed by arm64e ABI */
265 				fp = (addr64_t) ptrauth_strip((void *)fp, ptrauth_key_frame_pointer);
266 #endif
267 			} else {
268 				fp = ml_phys_read_word(((((vm_offset_t)ppn) << PAGE_SHIFT)) | (fp & PAGE_MASK));
269 			}
270 		} else {
271 			if (is_64_bit) {
272 				paniclog_append_noflush("%s\t  Could not read FP from frame at 0x%016llx\n", cur_marker, fp);
273 			} else {
274 				paniclog_append_noflush("%s\t  Could not read FP from frame at 0x%08x\n", cur_marker, (uint32_t)fp);
275 			}
276 			break;
277 		}
278 		/*
279 		 * Counter 'i' may == FP_MAX_NUM_TO_EVALUATE when running one
280 		 * extra round to check whether we have all frames in order to
281 		 * indicate (in)complete backtrace below. This happens in a case
282 		 * where total frame count and FP_MAX_NUM_TO_EVALUATE are equal.
283 		 * Do not capture anything.
284 		 */
285 		if (i < FP_MAX_NUM_TO_EVALUATE && lr) {
286 			if (is_64_bit) {
287 				paniclog_append_noflush("%s\t  lr: 0x%016llx  fp: 0x%016llx\n", cur_marker, lr, fp);
288 			} else {
289 				paniclog_append_noflush("%s\t  lr: 0x%08x  fp: 0x%08x\n", cur_marker, (uint32_t)lr, (uint32_t)fp);
290 			}
291 			raddrs[i] = lr;
292 		}
293 	} while ((++i <= FP_MAX_NUM_TO_EVALUATE) && (fp != topfp));
294 
295 	if (i > FP_MAX_NUM_TO_EVALUATE && fp != 0) {
296 		paniclog_append_noflush("Backtrace continues...\n");
297 	}
298 
299 	if (print_kexts_in_backtrace && i > 0) {
300 		kmod_panic_dump(&raddrs[0], i);
301 	}
302 }
303 
304 #define SANE_TASK_LIMIT 256
305 #define TOP_RUNNABLE_LIMIT 5
306 #define PANICLOG_UUID_BUF_SIZE 256
307 
308 extern void panic_print_vnodes(void);
309 
310 static void
panic_display_tpidrs(void)311 panic_display_tpidrs(void)
312 {
313 #if defined(__arm64__)
314 	paniclog_append_noflush("TPIDRx_ELy = {1: 0x%016llx  0: 0x%016llx  0ro: 0x%016llx }\n",
315 	    __builtin_arm_rsr64("TPIDR_EL1"), __builtin_arm_rsr64("TPIDR_EL0"),
316 	    __builtin_arm_rsr64("TPIDRRO_EL0"));
317 #endif //defined(__arm64__)
318 }
319 
320 
321 
322 static void
panic_display_hung_cpus_help(void)323 panic_display_hung_cpus_help(void)
324 {
325 #if defined(__arm64__)
326 	const uint32_t pcsr_offset = 0x90;
327 
328 	/*
329 	 * Print some info that might help in cases where nothing
330 	 * else does
331 	 */
332 	const ml_topology_info_t *info = ml_get_topology_info();
333 	if (info) {
334 		unsigned i, retry;
335 
336 		for (i = 0; i < info->num_cpus; i++) {
337 			ml_topology_cpu_t *cpu = &info->cpus[i];
338 			char cluster_name[16], cluster_letter;
339 
340 			switch (cpu->cluster_type) {
341 			case CLUSTER_TYPE_E:
342 				cluster_letter = 'E';
343 				break;
344 			case CLUSTER_TYPE_P:
345 				cluster_letter = 'P';
346 				break;
347 			default:
348 				cluster_letter = '?';
349 			}
350 			snprintf(cluster_name, sizeof(cluster_name), "%cACC%d", cluster_letter, cpu->cluster_id);
351 
352 			if (!PE_cpu_power_check_kdp(i)) {
353 				paniclog_append_noflush("CORE %u [%s] is offline, skipping\n", i, cluster_name);
354 				continue;
355 			}
356 			if (cpu->cpu_UTTDBG_regs) {
357 				volatile uint64_t *pcsr = (volatile uint64_t*)(cpu->cpu_UTTDBG_regs + pcsr_offset);
358 				volatile uint32_t *pcsrTrigger = (volatile uint32_t*)pcsr;
359 				uint64_t pc = 0;
360 
361 				// a number of retries are needed till this works
362 				for (retry = 1024; retry && !pc; retry--) {
363 					//a 32-bit read is required to make a PC sample be produced, else we'll only get a zero
364 					(void)*pcsrTrigger;
365 					pc = *pcsr;
366 				}
367 
368 				//postprocessing (same as astris does)
369 				if (pc >> 48) {
370 					pc |= 0xffff000000000000ull;
371 				}
372 				paniclog_append_noflush("CORE %u [%s] recently retired instr at 0x%016llx\n", i, cluster_name, pc);
373 			}
374 		}
375 	}
376 #endif //defined(__arm64__)
377 }
378 
379 
380 
381 static void
panic_display_pvhs_locked(void)382 panic_display_pvhs_locked(void)
383 {
384 }
385 
386 static void
panic_display_pvh_to_lock(void)387 panic_display_pvh_to_lock(void)
388 {
389 }
390 
391 static void
panic_display_last_pc_lr(void)392 panic_display_last_pc_lr(void)
393 {
394 #if defined(__arm64__)
395 	const int max_cpu = ml_get_max_cpu_number();
396 
397 	for (int cpu = 0; cpu <= max_cpu; cpu++) {
398 		cpu_data_t *current_cpu_datap = cpu_datap(cpu);
399 
400 		if (current_cpu_datap == NULL) {
401 			continue;
402 		}
403 
404 		if (current_cpu_datap == getCpuDatap()) {
405 			/**
406 			 * Skip printing the PC/LR if this is the CPU
407 			 * that initiated the panic.
408 			 */
409 			paniclog_append_noflush("CORE %u is the one that panicked. Check the full backtrace for details.\n", cpu);
410 			continue;
411 		}
412 
413 		paniclog_append_noflush("CORE %u: PC=0x%016llx, LR=0x%016llx, FP=0x%016llx\n", cpu,
414 		    current_cpu_datap->ipi_pc, (uint64_t)VM_KERNEL_STRIP_PTR(current_cpu_datap->ipi_lr),
415 		    (uint64_t)VM_KERNEL_STRIP_PTR(current_cpu_datap->ipi_fp));
416 	}
417 #endif
418 }
419 
420 #if CONFIG_EXCLAVES
421 static void
panic_report_exclaves_stackshot(void)422 panic_report_exclaves_stackshot(void)
423 {
424 	if (exclaves_panic_ss_status == EXCLAVES_PANIC_STACKSHOT_FOUND) {
425 		paniclog_append_noflush("** Exclaves panic stackshot found\n");
426 	} else if (exclaves_panic_ss_status == EXCLAVES_PANIC_STACKSHOT_NOT_FOUND) {
427 		paniclog_append_noflush("** Exclaves panic stackshot not found\n");
428 	} else if (exclaves_panic_ss_status == EXCLAVES_PANIC_STACKSHOT_DECODE_FAILED) {
429 		paniclog_append_noflush("!! Exclaves panic stackshot decode failed !!\n");
430 	}
431 }
432 #endif /* CONFIG_EXCLAVES */
433 
434 __attribute__((always_inline))
435 static inline void
print_backtrace_internal(thread_t thread,bool filesetKC)436 print_backtrace_internal(thread_t thread, bool filesetKC)
437 {
438 	uintptr_t cur_fp = (uintptr_t)__builtin_frame_address(0);
439 	const char              *nohilite_thread_marker = "\t";
440 
441 #if defined(HAS_APPLE_PAC)
442 	cur_fp = (addr64_t)ptrauth_strip((void *)cur_fp, ptrauth_key_frame_pointer);
443 #endif
444 
445 	if (cur_fp < VM_MAX_KERNEL_ADDRESS) {
446 		paniclog_append_noflush("Panicked thread: %p, backtrace: 0x%llx, tid: %llu\n",
447 		    thread, (addr64_t)cur_fp, thread_tid(thread));
448 #if __LP64__
449 		do_print_backtrace_internal(kernel_pmap, cur_fp, nohilite_thread_marker, TRUE, filesetKC);
450 #else
451 		do_print_backtrace_internal(kernel_pmap, cur_fp, nohilite_thread_marker, FALSE, filesetKC);
452 #endif
453 	} else {
454 		paniclog_append_noflush("Could not print panicked thread backtrace:"
455 		    "frame pointer outside kernel vm.\n");
456 	}
457 }
458 
459 static bool
is_filesetKC(void)460 is_filesetKC(void)
461 {
462 	kc_format_t     kc_format;
463 	bool            filesetKC = false;
464 
465 	__unused bool result = PE_get_primary_kc_format(&kc_format);
466 	assert(result == true);
467 	filesetKC = kc_format == KCFormatFileset;
468 	return filesetKC;
469 }
470 
471 
472 static void
do_print_all_panic_info(const char * message,uint64_t panic_options,const char * panic_initiator)473 do_print_all_panic_info(const char *message, uint64_t panic_options, const char *panic_initiator)
474 {
475 	int             logversion = PANICLOG_VERSION;
476 	thread_t        cur_thread = current_thread();
477 	task_t          task;
478 	struct proc    *proc;
479 	int             print_vnodes = 0;
480 
481 	/* end_marker_bytes set to 200 for printing END marker + stackshot summary info always */
482 	int bytes_traced = 0, bytes_remaining = 0, end_marker_bytes = 200;
483 	int bytes_uncompressed = 0;
484 	uint64_t bytes_used = 0ULL;
485 	int err = 0;
486 	char *stackshot_begin_loc = NULL;
487 	bool filesetKC = is_filesetKC();
488 	uint32_t panic_initiator_len = 0;
489 #if CONFIG_EXT_PANICLOG
490 	uint32_t ext_paniclog_bytes = 0;
491 #endif
492 
493 	if (panic_bt_depth != 0) {
494 		return;
495 	}
496 	panic_bt_depth++;
497 
498 	/* Truncate panic string to 1200 bytes */
499 	paniclog_append_noflush("Debugger message: %.1200s\n", message);
500 	if (debug_enabled) {
501 		paniclog_append_noflush("Device: %s\n",
502 		    ('\0' != gTargetTypeBuffer[0]) ? gTargetTypeBuffer : "Not set yet");
503 		paniclog_append_noflush("Hardware Model: %s\n",
504 		    ('\0' != gModelTypeBuffer[0]) ? gModelTypeBuffer:"Not set yet");
505 		paniclog_append_noflush("ECID: %02X%02X%02X%02X%02X%02X%02X%02X\n", gPlatformECID[7],
506 		    gPlatformECID[6], gPlatformECID[5], gPlatformECID[4], gPlatformECID[3],
507 		    gPlatformECID[2], gPlatformECID[1], gPlatformECID[0]);
508 		if (last_hwaccess_thread) {
509 			paniclog_append_noflush("AppleHWAccess Thread: 0x%llx\n", last_hwaccess_thread);
510 			if (!last_hwaccess_size) {
511 				paniclog_append_noflush("AppleHWAccess last access: no access data, this is unexpected.\n");
512 			} else {
513 				const char *typ = last_hwaccess_type ? "write" : "read";
514 				paniclog_append_noflush("AppleHWAccess last access: %s of size %u at address 0x%llx\n", typ, last_hwaccess_size, last_hwaccess_paddr);
515 			}
516 		}
517 		paniclog_append_noflush("Boot args: %s\n", PE_boot_args());
518 	}
519 	paniclog_append_noflush("Memory ID: 0x%x\n", gPlatformMemoryID);
520 	paniclog_append_noflush("OS release type: %.256s\n",
521 	    ('\0' != osreleasetype[0]) ? osreleasetype : "Not set yet");
522 	paniclog_append_noflush("OS version: %.256s\n",
523 	    ('\0' != osversion[0]) ? osversion : "Not set yet");
524 #if defined(XNU_TARGET_OS_BRIDGE)
525 	paniclog_append_noflush("macOS version: %.256s\n",
526 	    ('\0' != macosversion[0]) ? macosversion : "Not set");
527 #endif
528 	paniclog_append_noflush("Kernel version: %.512s\n", version);
529 
530 #if CONFIG_EXCLAVES
531 	exclaves_panic_append_info();
532 #endif
533 
534 	if (kernelcache_uuid_valid) {
535 		if (filesetKC) {
536 			paniclog_append_noflush("Fileset Kernelcache UUID: ");
537 		} else {
538 			paniclog_append_noflush("KernelCache UUID: ");
539 		}
540 		for (size_t index = 0; index < sizeof(uuid_t); index++) {
541 			paniclog_append_noflush("%02X", kernelcache_uuid[index]);
542 		}
543 		paniclog_append_noflush("\n");
544 	}
545 	panic_display_kernel_uuid();
546 
547 	if (bootsessionuuid_string[0] != '\0') {
548 		paniclog_append_noflush("Boot session UUID: %s\n", bootsessionuuid_string);
549 	} else {
550 		paniclog_append_noflush("Boot session UUID not yet initialized\n");
551 	}
552 
553 	paniclog_append_noflush("iBoot version: %.128s\n", iBoot_version);
554 #if defined(TARGET_OS_OSX) && defined(__arm64__)
555 	paniclog_append_noflush("iBoot Stage 2 version: %.128s\n", iBoot_Stage_2_version);
556 #endif /* defined(TARGET_OS_OSX) && defined(__arm64__) */
557 
558 	paniclog_append_noflush("secure boot?: %s\n", debug_enabled ? "NO": "YES");
559 	paniclog_append_noflush("roots installed: %lld\n", roots_installed);
560 #if defined(XNU_TARGET_OS_BRIDGE)
561 	paniclog_append_noflush("x86 EFI Boot State: ");
562 	if (PE_smc_stashed_x86_efi_boot_state != 0xFF) {
563 		paniclog_append_noflush("0x%x\n", PE_smc_stashed_x86_efi_boot_state);
564 	} else {
565 		paniclog_append_noflush("not available\n");
566 	}
567 	paniclog_append_noflush("x86 System State: ");
568 	if (PE_smc_stashed_x86_system_state != 0xFF) {
569 		paniclog_append_noflush("0x%x\n", PE_smc_stashed_x86_system_state);
570 	} else {
571 		paniclog_append_noflush("not available\n");
572 	}
573 	paniclog_append_noflush("x86 Power State: ");
574 	if (PE_smc_stashed_x86_power_state != 0xFF) {
575 		paniclog_append_noflush("0x%x\n", PE_smc_stashed_x86_power_state);
576 	} else {
577 		paniclog_append_noflush("not available\n");
578 	}
579 	paniclog_append_noflush("x86 Shutdown Cause: ");
580 	if (PE_smc_stashed_x86_shutdown_cause != 0xFF) {
581 		paniclog_append_noflush("0x%x\n", PE_smc_stashed_x86_shutdown_cause);
582 	} else {
583 		paniclog_append_noflush("not available\n");
584 	}
585 	paniclog_append_noflush("x86 Previous Power Transitions: ");
586 	if (PE_smc_stashed_x86_prev_power_transitions != UINT64_MAX) {
587 		paniclog_append_noflush("0x%llx\n", PE_smc_stashed_x86_prev_power_transitions);
588 	} else {
589 		paniclog_append_noflush("not available\n");
590 	}
591 	paniclog_append_noflush("PCIeUp link state: ");
592 	if (PE_pcie_stashed_link_state != UINT32_MAX) {
593 		paniclog_append_noflush("0x%x\n", PE_pcie_stashed_link_state);
594 	} else {
595 		paniclog_append_noflush("not available\n");
596 	}
597 	paniclog_append_noflush("macOS kernel slide: ");
598 	if (PE_nvram_stashed_x86_macos_slide != UINT64_MAX) {
599 		paniclog_append_noflush("%#llx\n", PE_nvram_stashed_x86_macos_slide);
600 	} else {
601 		paniclog_append_noflush("not available\n");
602 	}
603 #endif
604 	if (panic_data_buffers != NULL) {
605 		paniclog_append_noflush("%s data: ", panic_data_buffers->producer_name);
606 		uint8_t *panic_buffer_data = (uint8_t *) panic_data_buffers->buf;
607 		for (int i = 0; i < panic_data_buffers->len; i++) {
608 			paniclog_append_noflush("%02X", panic_buffer_data[i]);
609 		}
610 		paniclog_append_noflush("\n");
611 	}
612 	paniclog_append_noflush("Paniclog version: %d\n", logversion);
613 
614 	panic_display_kernel_aslr();
615 	panic_display_times();
616 	panic_display_zalloc();
617 	panic_display_hung_cpus_help();
618 	panic_display_tpidrs();
619 
620 
621 	panic_display_pvhs_locked();
622 	panic_display_pvh_to_lock();
623 	panic_display_last_pc_lr();
624 #if CONFIG_ECC_LOGGING
625 	panic_display_ecc_errors();
626 #endif /* CONFIG_ECC_LOGGING */
627 	panic_display_compressor_stats();
628 
629 #if DEVELOPMENT || DEBUG
630 	if (cs_debug_unsigned_exec_failures != 0 || cs_debug_unsigned_mmap_failures != 0) {
631 		paniclog_append_noflush("Unsigned code exec failures: %u\n", cs_debug_unsigned_exec_failures);
632 		paniclog_append_noflush("Unsigned code mmap failures: %u\n", cs_debug_unsigned_mmap_failures);
633 	}
634 #endif
635 
636 	// Highlight threads that used high amounts of CPU in the panic log if requested (historically requested for watchdog panics)
637 	if (panic_options & DEBUGGER_OPTION_PRINT_CPU_USAGE_PANICLOG) {
638 		thread_t        top_runnable[5] = {0};
639 		thread_t        thread;
640 		int                     total_cpu_usage = 0;
641 
642 		print_vnodes = 1;
643 
644 
645 		for (thread = (thread_t)queue_first(&threads);
646 		    PANIC_VALIDATE_PTR(thread) && !queue_end(&threads, (queue_entry_t)thread);
647 		    thread = (thread_t)queue_next(&thread->threads)) {
648 			total_cpu_usage += thread->cpu_usage;
649 
650 			// Look for the 5 runnable threads with highest priority
651 			if (thread->state & TH_RUN) {
652 				int                     k;
653 				thread_t        comparison_thread = thread;
654 
655 				for (k = 0; k < TOP_RUNNABLE_LIMIT; k++) {
656 					if (top_runnable[k] == 0) {
657 						top_runnable[k] = comparison_thread;
658 						break;
659 					} else if (comparison_thread->sched_pri > top_runnable[k]->sched_pri) {
660 						thread_t temp = top_runnable[k];
661 						top_runnable[k] = comparison_thread;
662 						comparison_thread = temp;
663 					} // if comparison thread has higher priority than previously saved thread
664 				} // loop through highest priority runnable threads
665 			} // Check if thread is runnable
666 		} // Loop through all threads
667 
668 		// Print the relevant info for each thread identified
669 		paniclog_append_noflush("Total cpu_usage: %d\n", total_cpu_usage);
670 		paniclog_append_noflush("Thread task pri cpu_usage\n");
671 
672 		for (int i = 0; i < TOP_RUNNABLE_LIMIT; i++) {
673 			if (top_runnable[i] &&
674 			    panic_get_thread_proc_task(top_runnable[i], &task, &proc) && proc) {
675 				char name[MAX_PROCNAME_LEN + 1];
676 				proc_name_kdp(proc, name, sizeof(name));
677 				paniclog_append_noflush("%p %s %d %d\n",
678 				    top_runnable[i], name, top_runnable[i]->sched_pri, top_runnable[i]->cpu_usage);
679 			}
680 		} // Loop through highest priority runnable threads
681 		paniclog_append_noflush("\n");
682 	}
683 
684 	// print current task info
685 	if (panic_get_thread_proc_task(cur_thread, &task, &proc)) {
686 		if (PANIC_VALIDATE_PTR(task->map) &&
687 		    PANIC_VALIDATE_PTR(task->map->pmap)) {
688 			ledger_amount_t resident = 0;
689 			if (task != kernel_task) {
690 				ledger_get_balance(task->ledger, task_ledgers.phys_mem, &resident);
691 				resident >>= VM_MAP_PAGE_SHIFT(task->map);
692 			}
693 			paniclog_append_noflush("Panicked task %p: %lld pages, %d threads: ",
694 			    task, resident, task->thread_count);
695 		} else {
696 			paniclog_append_noflush("Panicked task %p: %d threads: ",
697 			    task, task->thread_count);
698 		}
699 
700 		if (proc) {
701 			char            name[MAX_PROCNAME_LEN + 1];
702 			proc_name_kdp(proc, name, sizeof(name));
703 			paniclog_append_noflush("pid %d: %s", proc_pid(proc), name);
704 		} else {
705 			paniclog_append_noflush("unknown task");
706 		}
707 
708 		paniclog_append_noflush("\n");
709 	}
710 
711 	print_backtrace_internal(cur_thread, filesetKC);
712 
713 	paniclog_append_noflush("\n");
714 	dump_cpu_event_log(&paniclog_append_noflush);
715 
716 	paniclog_append_noflush("\n");
717 	if (filesetKC) {
718 		kext_dump_panic_lists(&paniclog_append_noflush);
719 		paniclog_append_noflush("\n");
720 	}
721 	panic_info->eph_panic_log_len = PE_get_offset_into_panic_region(debug_buf_ptr) - panic_info->eph_panic_log_offset;
722 	/* set the os version data in the panic header in the format 'Product Version (OS Version)' (only if they have been set) */
723 	if ((osversion[0] != '\0') && (osproductversion[0] != '\0')) {
724 		snprintf((char *)&panic_info->eph_os_version, sizeof(panic_info->eph_os_version), PANIC_HEADER_VERSION_FMT_STR,
725 		    osproductversion, osversion);
726 	}
727 #if defined(XNU_TARGET_OS_BRIDGE)
728 	if ((macosversion[0] != '\0') && (macosproductversion[0] != '\0')) {
729 		snprintf((char *)&panic_info->eph_macos_version, sizeof(panic_info->eph_macos_version), PANIC_HEADER_VERSION_FMT_STR,
730 		    macosproductversion, macosversion);
731 	}
732 #endif
733 	if (bootsessionuuid_string[0] != '\0') {
734 		memcpy(panic_info->eph_bootsessionuuid_string, bootsessionuuid_string,
735 		    sizeof(panic_info->eph_bootsessionuuid_string));
736 	}
737 	panic_info->eph_roots_installed = roots_installed;
738 
739 	if (panic_initiator != NULL) {
740 		bytes_remaining = debug_buf_size - (unsigned int)((uintptr_t)debug_buf_ptr - (uintptr_t)debug_buf_base);
741 		// If panic_initiator isn't null, safely copy up to MAX_PANIC_INITIATOR_SIZE
742 		panic_initiator_len = strnlen(panic_initiator, MAX_PANIC_INITIATOR_SIZE);
743 		// Calculate the bytes to write, accounting for remaining buffer space, and ensuring the lowest size we can have is 0
744 		panic_initiator_len = MAX(0, MIN(panic_initiator_len, bytes_remaining));
745 		panic_info->eph_panic_initiator_offset = (panic_initiator_len != 0) ? PE_get_offset_into_panic_region(debug_buf_ptr) : 0;
746 		panic_info->eph_panic_initiator_len = panic_initiator_len;
747 		memcpy(debug_buf_ptr, panic_initiator, panic_initiator_len);
748 		debug_buf_ptr += panic_initiator_len;
749 	}
750 
751 	if (debug_ack_timeout_count) {
752 		panic_info->eph_panic_flags |= EMBEDDED_PANIC_HEADER_FLAG_STACKSHOT_FAILED_DEBUGGERSYNC;
753 		panic_info->eph_other_log_offset = PE_get_offset_into_panic_region(debug_buf_ptr);
754 		paniclog_append_noflush("!! debugger synchronization failed, no stackshot !!\n");
755 	} else if (panic_stackshot_active()) {
756 		panic_info->eph_panic_flags |= EMBEDDED_PANIC_HEADER_FLAG_STACKSHOT_FAILED_NESTED;
757 		panic_info->eph_other_log_offset = PE_get_offset_into_panic_region(debug_buf_ptr);
758 		paniclog_append_noflush("!! panicked during stackshot, skipping panic stackshot !!\n");
759 	} else {
760 		/* Align the stackshot buffer to an 8-byte address (especially important for armv7k devices) */
761 		debug_buf_ptr += (8 - ((uintptr_t)debug_buf_ptr % 8));
762 		stackshot_begin_loc = debug_buf_ptr;
763 
764 		bytes_remaining = debug_buf_size - (unsigned int)((uintptr_t)stackshot_begin_loc - (uintptr_t)debug_buf_base);
765 		err = kcdata_memory_static_init(&kc_panic_data, (mach_vm_address_t)debug_buf_ptr,
766 		    KCDATA_BUFFER_BEGIN_COMPRESSED, bytes_remaining - end_marker_bytes,
767 		    KCFLAG_USE_MEMCOPY);
768 		if (err == KERN_SUCCESS) {
769 			uint64_t stackshot_flags = (STACKSHOT_GET_GLOBAL_MEM_STATS | STACKSHOT_SAVE_LOADINFO | STACKSHOT_KCDATA_FORMAT |
770 			    STACKSHOT_ENABLE_BT_FAULTING | STACKSHOT_ENABLE_UUID_FAULTING | STACKSHOT_FROM_PANIC | STACKSHOT_DO_COMPRESS |
771 			    STACKSHOT_DISABLE_LATENCY_INFO | STACKSHOT_NO_IO_STATS | STACKSHOT_THREAD_WAITINFO | STACKSHOT_GET_DQ |
772 			    STACKSHOT_COLLECT_SHAREDCACHE_LAYOUT);
773 
774 			err = kcdata_init_compress(&kc_panic_data, KCDATA_BUFFER_BEGIN_STACKSHOT, kdp_memcpy, KCDCT_ZLIB);
775 			if (err != KERN_SUCCESS) {
776 				panic_info->eph_panic_flags |= EMBEDDED_PANIC_HEADER_FLAG_COMPRESS_FAILED;
777 				stackshot_flags &= ~STACKSHOT_DO_COMPRESS;
778 			}
779 			if (filesetKC) {
780 				stackshot_flags |= STACKSHOT_SAVE_KEXT_LOADINFO;
781 			}
782 
783 			kdp_snapshot_preflight(-1, stackshot_begin_loc, bytes_remaining - end_marker_bytes,
784 			    stackshot_flags, &kc_panic_data, 0, 0);
785 			err = do_panic_stackshot(NULL);
786 			bytes_traced = kdp_stack_snapshot_bytes_traced();
787 			if (bytes_traced > 0 && !err) {
788 				debug_buf_ptr += bytes_traced;
789 				panic_info->eph_panic_flags |= EMBEDDED_PANIC_HEADER_FLAG_STACKSHOT_SUCCEEDED;
790 				panic_info->eph_stackshot_offset = PE_get_offset_into_panic_region(stackshot_begin_loc);
791 				panic_info->eph_stackshot_len = bytes_traced;
792 
793 				panic_info->eph_other_log_offset = PE_get_offset_into_panic_region(debug_buf_ptr);
794 #if CONFIG_EXCLAVES
795 				panic_report_exclaves_stackshot();
796 #endif /* CONFIG_EXCLAVES */
797 				if (stackshot_flags & STACKSHOT_DO_COMPRESS) {
798 					panic_info->eph_panic_flags |= EMBEDDED_PANIC_HEADER_FLAG_STACKSHOT_DATA_COMPRESSED;
799 					bytes_uncompressed = kdp_stack_snapshot_bytes_uncompressed();
800 					paniclog_append_noflush("\n** Stackshot Succeeded ** Bytes Traced %d (Uncompressed %d) **\n", bytes_traced, bytes_uncompressed);
801 				} else {
802 					paniclog_append_noflush("\n** Stackshot Succeeded ** Bytes Traced %d **\n", bytes_traced);
803 				}
804 			} else {
805 				bytes_used = kcdata_memory_get_used_bytes(&kc_panic_data);
806 #if CONFIG_EXCLAVES
807 				panic_report_exclaves_stackshot();
808 #endif /* CONFIG_EXCLAVES */
809 				if (bytes_used > 0) {
810 					/* Zero out the stackshot data */
811 					bzero(stackshot_begin_loc, bytes_used);
812 					panic_info->eph_panic_flags |= EMBEDDED_PANIC_HEADER_FLAG_STACKSHOT_FAILED_INCOMPLETE;
813 
814 					panic_info->eph_other_log_offset = PE_get_offset_into_panic_region(debug_buf_ptr);
815 					paniclog_append_noflush("\n** Stackshot Incomplete ** Bytes Filled %llu, err %d **\n", bytes_used, err);
816 				} else {
817 					bzero(stackshot_begin_loc, bytes_used);
818 					panic_info->eph_panic_flags |= EMBEDDED_PANIC_HEADER_FLAG_STACKSHOT_FAILED_ERROR;
819 
820 					panic_info->eph_other_log_offset = PE_get_offset_into_panic_region(debug_buf_ptr);
821 					paniclog_append_noflush("\n!! Stackshot Failed !! Bytes Traced %d, err %d\n", bytes_traced, err);
822 				}
823 			}
824 		} else {
825 			panic_info->eph_panic_flags |= EMBEDDED_PANIC_HEADER_FLAG_STACKSHOT_FAILED_ERROR;
826 			panic_info->eph_other_log_offset = PE_get_offset_into_panic_region(debug_buf_ptr);
827 			paniclog_append_noflush("\n!! Stackshot Failed !!\nkcdata_memory_static_init returned %d", err);
828 		}
829 	}
830 
831 	ksancov_on_panic_log();
832 
833 #if CONFIG_EXT_PANICLOG
834 	// Write ext paniclog at the end of the paniclog region.
835 	ext_paniclog_bytes = ext_paniclog_write_panicdata();
836 	panic_info->eph_ext_paniclog_offset = (ext_paniclog_bytes != 0) ?
837 	    PE_get_offset_into_panic_region((debug_buf_base + debug_buf_size) - ext_paniclog_bytes) :
838 	    0;
839 	panic_info->eph_ext_paniclog_len = ext_paniclog_bytes;
840 #endif
841 
842 	assert(panic_info->eph_other_log_offset != 0);
843 
844 	if (print_vnodes != 0) {
845 		panic_print_vnodes();
846 	}
847 
848 	panic_bt_depth--;
849 }
850 
851 /*
852  * Entry to print_all_panic_info is serialized by the debugger lock
853  */
854 static void
print_all_panic_info(const char * message,uint64_t panic_options,const char * panic_initiator)855 print_all_panic_info(const char *message, uint64_t panic_options, const char *panic_initiator)
856 {
857 	unsigned int initial_not_in_kdp = not_in_kdp;
858 
859 	cpu_data_t * cpu_data_ptr = getCpuDatap();
860 
861 	assert(cpu_data_ptr->PAB_active == FALSE);
862 	cpu_data_ptr->PAB_active = TRUE;
863 
864 	/*
865 	 * Because print all backtraces uses the pmap routines, it needs to
866 	 * avoid taking pmap locks.  Right now, this is conditionalized on
867 	 * not_in_kdp.
868 	 */
869 	not_in_kdp = 0;
870 	do_print_all_panic_info(message, panic_options, panic_initiator);
871 
872 	not_in_kdp = initial_not_in_kdp;
873 
874 	cpu_data_ptr->PAB_active = FALSE;
875 }
876 
877 void
print_curr_backtrace(void)878 print_curr_backtrace(void)
879 {
880 	print_backtrace_internal(current_thread(), is_filesetKC());
881 }
882 
883 void
panic_display_times()884 panic_display_times()
885 {
886 	if (kdp_clock_is_locked()) {
887 		paniclog_append_noflush("Warning: clock is locked.  Can't get time\n");
888 		return;
889 	}
890 
891 	extern lck_ticket_t clock_lock;
892 	extern lck_grp_t clock_lock_grp;
893 
894 	if ((is_clock_configured) && (lck_ticket_lock_try(&clock_lock, &clock_lock_grp))) {
895 		clock_sec_t     secs, boot_secs;
896 		clock_usec_t    usecs, boot_usecs;
897 
898 		lck_ticket_unlock(&clock_lock);
899 
900 		clock_get_calendar_microtime(&secs, &usecs);
901 		clock_get_boottime_microtime(&boot_secs, &boot_usecs);
902 
903 		paniclog_append_noflush("mach_absolute_time: 0x%llx\n", mach_absolute_time());
904 		paniclog_append_noflush("Epoch Time:        sec       usec\n");
905 		paniclog_append_noflush("  Boot    : 0x%08x 0x%08x\n", (unsigned int)boot_secs, (unsigned int)boot_usecs);
906 		paniclog_append_noflush("  Sleep   : 0x%08x 0x%08x\n", (unsigned int)gIOLastSleepTime.tv_sec, (unsigned int)gIOLastSleepTime.tv_usec);
907 		paniclog_append_noflush("  Wake    : 0x%08x 0x%08x\n", (unsigned int)gIOLastWakeTime.tv_sec, (unsigned int)gIOLastWakeTime.tv_usec);
908 		paniclog_append_noflush("  Calendar: 0x%08x 0x%08x\n\n", (unsigned int)secs, (unsigned int)usecs);
909 	}
910 }
911 
912 void
panic_print_symbol_name(vm_address_t search)913 panic_print_symbol_name(vm_address_t search)
914 {
915 #pragma unused(search)
916 	// empty stub. Really only used on x86_64.
917 	return;
918 }
919 
920 void
SavePanicInfo(const char * message,__unused void * panic_data,uint64_t panic_options,const char * panic_initiator)921 SavePanicInfo(
922 	const char *message, __unused void *panic_data, uint64_t panic_options, const char* panic_initiator)
923 {
924 	/*
925 	 * This should be initialized by the time we get here, but
926 	 * if it is not, asserting about it will be of no use (it will
927 	 * come right back to here), so just loop right here and now.
928 	 * This prevents early-boot panics from becoming recursive and
929 	 * thus makes them easier to debug. If you attached to a device
930 	 * and see your PC here, look down a few frames to see your
931 	 * early-boot panic there.
932 	 */
933 	while (!panic_info || panic_info->eph_panic_log_offset == 0) {
934 		// rdar://87170225 (PanicHardening: audit panic code for naked spinloops)
935 		// rdar://88094367 (Add test hooks for panic at different stages in XNU)
936 		;
937 	}
938 
939 	if (panic_options & DEBUGGER_OPTION_PANICLOGANDREBOOT) {
940 		panic_info->eph_panic_flags  |= EMBEDDED_PANIC_HEADER_FLAG_BUTTON_RESET_PANIC;
941 	}
942 
943 	if (panic_options & DEBUGGER_OPTION_COMPANION_PROC_INITIATED_PANIC) {
944 		panic_info->eph_panic_flags |= EMBEDDED_PANIC_HEADER_FLAG_COMPANION_PROC_INITIATED_PANIC;
945 	}
946 
947 	if (panic_options & DEBUGGER_OPTION_INTEGRATED_COPROC_INITIATED_PANIC) {
948 		panic_info->eph_panic_flags |= EMBEDDED_PANIC_HEADER_FLAG_INTEGRATED_COPROC_INITIATED_PANIC;
949 	}
950 
951 	if (panic_options & DEBUGGER_OPTION_USERSPACE_INITIATED_PANIC) {
952 		panic_info->eph_panic_flags |= EMBEDDED_PANIC_HEADER_FLAG_USERSPACE_INITIATED_PANIC;
953 	}
954 
955 #if defined(XNU_TARGET_OS_BRIDGE)
956 	panic_info->eph_x86_power_state = PE_smc_stashed_x86_power_state;
957 	panic_info->eph_x86_efi_boot_state = PE_smc_stashed_x86_efi_boot_state;
958 	panic_info->eph_x86_system_state = PE_smc_stashed_x86_system_state;
959 #endif
960 
961 	/*
962 	 * On newer targets, panic data is stored directly into the iBoot panic region.
963 	 * If we re-enter SavePanicInfo (e.g. on a double panic) on such a target, update the
964 	 * panic CRC so that iBoot can hopefully find *something* useful in the panic region.
965 	 */
966 	if (PanicInfoSaved && (debug_buf_base >= (char*)gPanicBase) && (debug_buf_base < (char*)gPanicBase + gPanicSize)) {
967 		unsigned int pi_size = (unsigned int)(debug_buf_ptr - gPanicBase);
968 		PE_update_panic_crc((unsigned char*)gPanicBase, &pi_size);
969 		PE_sync_panic_buffers(); // extra precaution; panic path likely isn't reliable if we're here
970 	}
971 
972 	if (PanicInfoSaved || (debug_buf_size == 0)) {
973 		return;
974 	}
975 
976 	PanicInfoSaved = TRUE;
977 
978 
979 	print_all_panic_info(message, panic_options, panic_initiator);
980 
981 	assert(panic_info->eph_panic_log_len != 0);
982 	panic_info->eph_other_log_len = PE_get_offset_into_panic_region(debug_buf_ptr) - panic_info->eph_other_log_offset;
983 
984 	PEHaltRestart(kPEPanicSync);
985 
986 	/*
987 	 * Notifies registered IOPlatformPanicAction callbacks
988 	 * (which includes one to disable the memcache) and flushes
989 	 * the buffer contents from the cache
990 	 */
991 	paniclog_flush();
992 }
993 
994 void
paniclog_flush()995 paniclog_flush()
996 {
997 	unsigned int panicbuf_length = 0;
998 
999 	panicbuf_length = (unsigned int)(debug_buf_ptr - gPanicBase);
1000 	if (!debug_buf_ptr || !panicbuf_length) {
1001 		return;
1002 	}
1003 
1004 	/*
1005 	 * Updates the log length of the last part of the panic log.
1006 	 */
1007 	panic_info->eph_other_log_len = PE_get_offset_into_panic_region(debug_buf_ptr) - panic_info->eph_other_log_offset;
1008 
1009 	/*
1010 	 * Updates the metadata at the beginning of the panic buffer,
1011 	 * updates the CRC.
1012 	 */
1013 	PE_update_panic_crc((unsigned char *)gPanicBase, &panicbuf_length);
1014 
1015 	/*
1016 	 * This is currently unused by platform KEXTs on embedded but is
1017 	 * kept for compatibility with the published IOKit interfaces.
1018 	 */
1019 	PESavePanicInfo((unsigned char *)gPanicBase, panicbuf_length);
1020 
1021 	PE_sync_panic_buffers();
1022 }
1023 
1024 #if CONFIG_SPTM
1025 /*
1026  * Patch thread state to appear as if a debugger stop IPI occurred, when a thread
1027  * is parked in SPTM panic loop. This allows stackshot to proceed as usual.
1028  */
1029 static void
DebuggerPatchupThreadState(int cpu,xnu_saved_registers_t * regp)1030 DebuggerPatchupThreadState(
1031 	int cpu, xnu_saved_registers_t *regp)
1032 {
1033 	cpu_data_t         *target_cpu_datap;
1034 	arm_saved_state_t  *statep;
1035 	vm_offset_t        kstackptr;
1036 
1037 	target_cpu_datap = (cpu_data_t *)CpuDataEntries[cpu].cpu_data_vaddr;
1038 	statep = target_cpu_datap->cpu_active_thread->machine.kpcb;
1039 	kstackptr = (vm_offset_t)target_cpu_datap->cpu_active_thread->machine.kstackptr;
1040 
1041 	target_cpu_datap->ipi_pc = regp->pc;
1042 	target_cpu_datap->ipi_lr = regp->lr;
1043 	target_cpu_datap->ipi_fp = regp->fp;
1044 
1045 	if (statep != NULL) {
1046 		statep->ss_64.fp = regp->fp;
1047 		statep->ss_64.lr = regp->lr;
1048 		statep->ss_64.sp = regp->sp;
1049 		statep->ss_64.pc = regp->pc;
1050 	} else if ((void *)kstackptr != NULL) {
1051 		arm_kernel_saved_state_t *kstatep = (arm_kernel_saved_state_t *)kstackptr;
1052 		kstatep->fp = regp->fp;
1053 		kstatep->lr = regp->lr;
1054 		kstatep->sp = regp->sp;
1055 	}
1056 }
1057 #endif
1058 
1059 /*
1060  * @function DebuggerXCallEnter
1061  *
1062  * @abstract IPI other cores so this core can run in a single-threaded context.
1063  *
1064  * @discussion This function should be called with the debugger lock held.  It
1065  * signals the other cores to go into a busy loop so this core can run in a
1066  * single-threaded context and inspect kernel memory.
1067  *
1068  * @param proceed_on_sync_failure If true, then go ahead and try to debug even
1069  * if we can't synch with the other cores.  This is inherently unsafe and should
1070  * only be used if the kernel is going down in flames anyway.
1071  *
1072  * @param is_stackshot If true, this is a stackshot request.
1073  *
1074  * @result returns KERN_OPERATION_TIMED_OUT if synchronization times out and
1075  * proceed_on_sync_failure is false.
1076  */
1077 kern_return_t
DebuggerXCallEnter(boolean_t proceed_on_sync_failure,bool is_stackshot)1078 DebuggerXCallEnter(
1079 	boolean_t proceed_on_sync_failure, bool is_stackshot)
1080 {
1081 	uint64_t max_mabs_time, current_mabs_time;
1082 	int cpu;
1083 	int timeout_cpu = -1;
1084 	int max_cpu;
1085 	unsigned int sync_pending;
1086 	cpu_data_t      *target_cpu_datap;
1087 	cpu_data_t      *cpu_data_ptr = getCpuDatap();
1088 
1089 	/* Check for nested debugger entry. */
1090 	cpu_data_ptr->debugger_active++;
1091 	if (cpu_data_ptr->debugger_active != 1) {
1092 		return KERN_SUCCESS;
1093 	}
1094 
1095 	/*
1096 	 * If debugger_sync is not 0, someone responded excessively late to the last
1097 	 * debug request (we zero the sync variable in the return function).  Zero it
1098 	 * again here.  This should prevent us from getting out of sync (heh) and
1099 	 * timing out on every entry to the debugger if we timeout once.
1100 	 */
1101 
1102 	os_atomic_store(&debugger_sync, 0, relaxed);
1103 	os_atomic_store(&mp_kdp_trap, 1, relaxed);
1104 	os_atomic_store(&debug_cpus_spinning, 0, relaxed);
1105 	trap_is_stackshot = is_stackshot;
1106 
1107 
1108 	/*
1109 	 * Try to signal all CPUs (except ourselves, of course).  Use debugger_sync to
1110 	 * synchronize with every CPU that we appeared to signal successfully (cpu_signal
1111 	 * is not synchronous).
1112 	 */
1113 	max_cpu = ml_get_max_cpu_number();
1114 
1115 	boolean_t immediate_halt = FALSE;
1116 	if (proceed_on_sync_failure && force_immediate_debug_halt) {
1117 		immediate_halt = TRUE;
1118 	}
1119 
1120 	if (!immediate_halt) {
1121 		for (cpu = 0; cpu <= max_cpu; cpu++) {
1122 			target_cpu_datap = (cpu_data_t *)CpuDataEntries[cpu].cpu_data_vaddr;
1123 
1124 			if ((target_cpu_datap == NULL) || (target_cpu_datap == cpu_data_ptr)) {
1125 				continue;
1126 			}
1127 
1128 			kern_return_t ret = cpu_signal(target_cpu_datap, SIGPdebug, (void *)NULL, NULL);
1129 			if (ret == KERN_SUCCESS) {
1130 				os_atomic_inc(&debugger_sync, relaxed);
1131 				os_atomic_inc(&debug_cpus_spinning, relaxed);
1132 			} else {
1133 				kprintf("%s: cpu_signal failed. cpu=%d ret=%d proceed=%d\n", __func__, cpu, ret, proceed_on_sync_failure);
1134 			}
1135 		}
1136 
1137 		max_mabs_time = os_atomic_load(&debug_ack_timeout, relaxed);
1138 
1139 		if (max_mabs_time > 0) {
1140 			current_mabs_time = mach_absolute_time();
1141 			max_mabs_time += current_mabs_time;
1142 			assert(max_mabs_time > current_mabs_time);
1143 		}
1144 
1145 		/*
1146 		 * Wait for DEBUG_ACK_TIMEOUT ns for a response from everyone we IPI'd.  If we
1147 		 * timeout, that is simply too bad; we don't have a true NMI, and one CPU may be
1148 		 * uninterruptibly spinning on someone else.  The best we can hope for is that
1149 		 * all other CPUs have either responded or are spinning in a context that is
1150 		 * debugger safe.
1151 		 */
1152 		do {
1153 			current_mabs_time = mach_absolute_time();
1154 			sync_pending = os_atomic_load(&debugger_sync, acquire);
1155 		} while ((sync_pending != 0) && (max_mabs_time == 0 || current_mabs_time < max_mabs_time));
1156 	}
1157 
1158 	if (!immediate_halt && max_mabs_time > 0 && current_mabs_time >= max_mabs_time) {
1159 		/*
1160 		 * We timed out trying to IPI the other CPUs. Skip counting any CPUs that
1161 		 * are offline; then we must account for the remainder, either counting
1162 		 * them as halted, or trying to dbgwrap them to get them to halt in the
1163 		 * case where the system is going down and we are running a dev fused
1164 		 * device.
1165 		 */
1166 		__builtin_arm_dmb(DMB_ISH);
1167 		for (cpu = 0; cpu <= max_cpu; cpu++) {
1168 			target_cpu_datap = (cpu_data_t *)CpuDataEntries[cpu].cpu_data_vaddr;
1169 
1170 			if ((target_cpu_datap == NULL) || (target_cpu_datap == cpu_data_ptr)) {
1171 				continue;
1172 			}
1173 			if (!(target_cpu_datap->cpu_signal & SIGPdebug)) {
1174 				continue;
1175 			}
1176 			if (processor_array[cpu]->state <= PROCESSOR_PENDING_OFFLINE) {
1177 				int dbg_sync_count;
1178 
1179 				/*
1180 				 * This is a processor that was successfully sent a SIGPdebug signal
1181 				 * but which hasn't acknowledged it because it went offline with
1182 				 * interrupts disabled before the IPI was delivered, so count it
1183 				 * as halted here.
1184 				 */
1185 				dbg_sync_count = os_atomic_dec(&debugger_sync, relaxed);
1186 				kprintf("%s>found CPU %d offline, debugger_sync=%d\n", __FUNCTION__, cpu, dbg_sync_count);
1187 				continue;
1188 			}
1189 			kprintf("%s>Debugger synch pending on cpu %d\n", __FUNCTION__, cpu);
1190 			timeout_cpu = cpu;
1191 #if CONFIG_SPTM
1192 			if (proceed_on_sync_failure) {
1193 				/*
1194 				 * If a core is spinning in the SPTM panic loop, consider it
1195 				 * as sync'd, and try to patch up the thread state from the
1196 				 * SPTM callee saved registers.
1197 				 */
1198 				bool sptm_panic_loop = false;
1199 				vm_offset_t base = other_percpu_base(cpu);
1200 				pmap_sptm_percpu_data_t *sptm_pcpu = PERCPU_GET_WITH_BASE(base, pmap_sptm_percpu);
1201 				uint64_t sptm_cpuid = sptm_pcpu->sptm_cpu_id;
1202 
1203 				if (sptm_get_cpu_state(sptm_cpuid, CPUSTATE_PANIC_SPIN, &sptm_panic_loop)
1204 				    == SPTM_SUCCESS && sptm_panic_loop) {
1205 					xnu_saved_registers_t regs;
1206 
1207 					if (sptm_copy_callee_saved_state(sptm_cpuid, &regs)
1208 					    == LIBSPTM_SUCCESS) {
1209 						DebuggerPatchupThreadState(cpu, &regs);
1210 					}
1211 
1212 					kprintf("%s>found CPU %d in SPTM\n", __FUNCTION__, cpu);
1213 					os_atomic_dec(&debugger_sync, relaxed);
1214 				}
1215 			}
1216 #endif
1217 		}
1218 
1219 		if (debugger_sync == 0) {
1220 			return KERN_SUCCESS;
1221 		} else if (!proceed_on_sync_failure) {
1222 			panic("%s>Debugger synch pending on cpu %d\n",
1223 			    __FUNCTION__, timeout_cpu);
1224 		}
1225 	}
1226 	if (immediate_halt || (max_mabs_time > 0 && current_mabs_time >= max_mabs_time)) {
1227 		if (immediate_halt) {
1228 			__builtin_arm_dmb(DMB_ISH);
1229 		}
1230 		for (cpu = 0; cpu <= max_cpu; cpu++) {
1231 			target_cpu_datap = (cpu_data_t *)CpuDataEntries[cpu].cpu_data_vaddr;
1232 
1233 			if ((target_cpu_datap == NULL) || (target_cpu_datap == cpu_data_ptr)) {
1234 				continue;
1235 			}
1236 			paniclog_append_noflush("Attempting to forcibly halt cpu %d\n", cpu);
1237 			dbgwrap_status_t halt_status = ml_dbgwrap_halt_cpu(cpu, 0);
1238 			if (halt_status < 0) {
1239 				paniclog_append_noflush("cpu %d failed to halt with error %d: %s\n", cpu, halt_status, ml_dbgwrap_strerror(halt_status));
1240 			} else {
1241 				if (halt_status > 0) {
1242 					paniclog_append_noflush("cpu %d halted with warning %d: %s\n", cpu, halt_status, ml_dbgwrap_strerror(halt_status));
1243 				}
1244 				target_cpu_datap->halt_status = CPU_HALTED;
1245 			}
1246 		}
1247 		for (cpu = 0; cpu <= max_cpu; cpu++) {
1248 			target_cpu_datap = (cpu_data_t *)CpuDataEntries[cpu].cpu_data_vaddr;
1249 
1250 			if ((target_cpu_datap == NULL) || (target_cpu_datap == cpu_data_ptr)) {
1251 				continue;
1252 			}
1253 			dbgwrap_status_t halt_status = ml_dbgwrap_halt_cpu_with_state(cpu,
1254 			    NSEC_PER_SEC, &target_cpu_datap->halt_state);
1255 			if ((halt_status < 0) || (halt_status == DBGWRAP_WARN_CPU_OFFLINE)) {
1256 				paniclog_append_noflush("Unable to obtain state for cpu %d with status %d: %s\n", cpu, halt_status, ml_dbgwrap_strerror(halt_status));
1257 				debug_ack_timeout_count++;
1258 			} else {
1259 				paniclog_append_noflush("cpu %d successfully halted\n", cpu);
1260 				target_cpu_datap->halt_status = CPU_HALTED_WITH_STATE;
1261 			}
1262 		}
1263 		if (immediate_halt) {
1264 			paniclog_append_noflush("Immediate halt requested on all cores\n");
1265 		} else {
1266 			paniclog_append_noflush("Debugger synchronization timed out; timeout %llu nanoseconds\n",
1267 			    os_atomic_load(&debug_ack_timeout, relaxed));
1268 		}
1269 	}
1270 	return KERN_SUCCESS;
1271 }
1272 
1273 /*
1274  * @function DebuggerXCallReturn
1275  *
1276  * @abstract Resume normal multicore operation after DebuggerXCallEnter()
1277  *
1278  * @discussion This function should be called with debugger lock held.
1279  */
1280 void
DebuggerXCallReturn(void)1281 DebuggerXCallReturn(
1282 	void)
1283 {
1284 	cpu_data_t      *cpu_data_ptr = getCpuDatap();
1285 	uint64_t max_mabs_time, current_mabs_time;
1286 
1287 	cpu_data_ptr->debugger_active--;
1288 	if (cpu_data_ptr->debugger_active != 0) {
1289 		return;
1290 	}
1291 
1292 	os_atomic_store(&mp_kdp_trap, 0, release);
1293 	os_atomic_store(&debugger_sync, 0, relaxed);
1294 
1295 	max_mabs_time = os_atomic_load(&debug_ack_timeout, relaxed);
1296 
1297 	if (max_mabs_time > 0) {
1298 		current_mabs_time = mach_absolute_time();
1299 		max_mabs_time += current_mabs_time;
1300 		assert(max_mabs_time > current_mabs_time);
1301 	}
1302 
1303 	/*
1304 	 * Wait for other CPUs to stop spinning on mp_kdp_trap (see DebuggerXCall).
1305 	 * It's possible for one or more CPUs to not decrement debug_cpus_spinning,
1306 	 * since they may be stuck somewhere else with interrupts disabled.
1307 	 * Wait for DEBUG_ACK_TIMEOUT ns for a response and move on if we don't get it.
1308 	 *
1309 	 * Note that the same is done in DebuggerXCallEnter, when we wait for other
1310 	 * CPUS to update debugger_sync. If we time out, let's hope for all CPUs to be
1311 	 * spinning in a debugger-safe context
1312 	 */
1313 	while ((os_atomic_load_exclusive(&debug_cpus_spinning, acquire) != 0) &&
1314 	    (max_mabs_time == 0 || current_mabs_time < max_mabs_time)) {
1315 		__builtin_arm_wfe();
1316 		current_mabs_time = mach_absolute_time();
1317 	}
1318 	os_atomic_clear_exclusive();
1319 
1320 	// checking debug_ack_timeout != 0 is a workaround for rdar://124242354
1321 	if (current_mabs_time >= max_mabs_time && os_atomic_load(&debug_ack_timeout, relaxed) != 0) {
1322 		panic("Resuming from debugger synchronization failed: waited %llu nanoseconds\n", os_atomic_load(&debug_ack_timeout, relaxed));
1323 	}
1324 }
1325 
1326 extern void wait_while_mp_kdp_trap(bool check_SIGPdebug);
1327 /*
1328  * Spin while mp_kdp_trap is set.
1329  *
1330  * processor_offline() calls this with check_SIGPdebug=true
1331  * to break out of the spin loop if the cpu has SIGPdebug
1332  * pending.
1333  */
1334 void
wait_while_mp_kdp_trap(bool check_SIGPdebug)1335 wait_while_mp_kdp_trap(bool check_SIGPdebug)
1336 {
1337 	bool found_mp_kdp_trap = false;
1338 	bool found_SIGPdebug = false;
1339 
1340 	while (os_atomic_load_exclusive(&mp_kdp_trap, acquire) != 0) {
1341 		found_mp_kdp_trap = true;
1342 		if (check_SIGPdebug && cpu_has_SIGPdebug_pending()) {
1343 			found_SIGPdebug = true;
1344 			break;
1345 		}
1346 		__builtin_arm_wfe();
1347 	}
1348 	os_atomic_clear_exclusive();
1349 
1350 	if (check_SIGPdebug && found_mp_kdp_trap) {
1351 		kprintf("%s>found_mp_kdp_trap=true found_SIGPdebug=%s\n", __FUNCTION__, found_SIGPdebug ? "true" : "false");
1352 	}
1353 }
1354 
1355 void
DebuggerXCall(void * ctx)1356 DebuggerXCall(
1357 	void            *ctx)
1358 {
1359 	boolean_t               save_context = FALSE;
1360 	vm_offset_t             kstackptr = 0;
1361 	arm_saved_state_t       *regs = (arm_saved_state_t *) ctx;
1362 
1363 	if (regs != NULL) {
1364 #if defined(__arm64__)
1365 		current_cpu_datap()->ipi_pc = (uint64_t)get_saved_state_pc(regs);
1366 		current_cpu_datap()->ipi_lr = (uint64_t)get_saved_state_lr(regs);
1367 		current_cpu_datap()->ipi_fp = (uint64_t)get_saved_state_fp(regs);
1368 		save_context = PSR64_IS_KERNEL(get_saved_state_cpsr(regs));
1369 #endif
1370 	}
1371 
1372 	kstackptr = (vm_offset_t)current_thread()->machine.kstackptr;
1373 
1374 #if defined(__arm64__)
1375 	arm_kernel_saved_state_t *state = (arm_kernel_saved_state_t *)kstackptr;
1376 
1377 	if (save_context) {
1378 		/* Save the interrupted context before acknowledging the signal */
1379 		current_thread()->machine.kpcb = regs;
1380 	} else if (regs) {
1381 		/* zero old state so machine_trace_thread knows not to backtrace it */
1382 		state->fp = 0;
1383 		state->pc_was_in_userspace = true;
1384 		state->lr = 0;
1385 		state->sp = 0;
1386 		state->ssbs = 0;
1387 		state->uao = 0;
1388 		state->dit = 0;
1389 #if HAS_MTE
1390 		state->tco = 0;
1391 #endif
1392 	}
1393 #endif
1394 
1395 	/*
1396 	 * When running in serial mode, the core capturing the dump may hold interrupts disabled
1397 	 * for a time longer than the timeout. That path includes logic to reset the timestamp
1398 	 * so that we do not eventually trigger the interrupt timeout assert().
1399 	 *
1400 	 * Here we check whether other cores have already gone over the timeout at this point
1401 	 * before spinning, so we at least cover the IPI reception path. After spinning, however,
1402 	 * we reset the timestamp so as to avoid hitting the interrupt timeout assert().
1403 	 */
1404 	if ((serialmode & SERIALMODE_OUTPUT) || trap_is_stackshot) {
1405 		ml_interrupt_masked_debug_end();
1406 	}
1407 
1408 	/*
1409 	 * Before we decrement debugger sync, do stackshot preflight work (if applicable).
1410 	 * Namely, we want to signal that we're available to do stackshot work, and we need to
1411 	 * signal so before the stackshot-calling CPU starts work.
1412 	 */
1413 
1414 	if (trap_is_stackshot) {
1415 		stackshot_cpu_preflight();
1416 	}
1417 
1418 	os_atomic_dec(&debugger_sync, release);
1419 
1420 	/* If we trapped because we're doing a stackshot, do our work first. */
1421 	if (trap_is_stackshot) {
1422 		stackshot_aux_cpu_entry();
1423 	}
1424 
1425 
1426 	wait_while_mp_kdp_trap(false);
1427 
1428 	/**
1429 	 * Alert the triggering CPU that this CPU is done spinning. The CPU that
1430 	 * signalled all of the other CPUs will wait (in DebuggerXCallReturn) for
1431 	 * all of the CPUs to exit the above loop before continuing.
1432 	 */
1433 	os_atomic_dec(&debug_cpus_spinning, release);
1434 
1435 #if SCHED_HYGIENE_DEBUG
1436 	/*
1437 	 * We also abandon the measurement for preemption disable
1438 	 * timeouts, if any. Normally, time in interrupt handlers would be
1439 	 * subtracted from preemption disable time, and this will happen
1440 	 * up to this point here, but since we here "end" the interrupt
1441 	 * handler prematurely (from the point of view of interrupt masked
1442 	 * debugging), the time spinning would otherwise still be
1443 	 * attributed to preemption disable time, and potentially trigger
1444 	 * an event, which could be a panic.
1445 	 */
1446 	abandon_preemption_disable_measurement();
1447 
1448 	if ((serialmode & SERIALMODE_OUTPUT) || trap_is_stackshot) {
1449 		ml_interrupt_masked_debug_start((void *)current_thread()->machine.int_handler_addr, current_thread()->machine.int_type);
1450 	}
1451 #endif /* SCHED_HYGIENE_DEBUG */
1452 
1453 #if defined(__arm64__)
1454 	current_thread()->machine.kpcb = NULL;
1455 #endif /* defined(__arm64__) */
1456 
1457 	/* Any cleanup for our pushed context should go here */
1458 }
1459 
1460 void
DebuggerCall(unsigned int reason,void * ctx)1461 DebuggerCall(
1462 	unsigned int    reason,
1463 	void            *ctx)
1464 {
1465 #if     !MACH_KDP
1466 #pragma unused(reason,ctx)
1467 #endif /* !MACH_KDP */
1468 
1469 #if ALTERNATE_DEBUGGER
1470 	alternate_debugger_enter();
1471 #endif
1472 
1473 #if     MACH_KDP
1474 	kdp_trap(reason, (struct arm_saved_state *)ctx);
1475 #else
1476 	/* TODO: decide what to do if no debugger config */
1477 #endif
1478 }
1479 
1480 boolean_t
bootloader_valid_page(ppnum_t ppn)1481 bootloader_valid_page(ppnum_t ppn)
1482 {
1483 	return pmap_bootloader_page(ppn);
1484 }
1485