xref: /xnu-12377.81.4/osfmk/arm/model_dep.c (revision 043036a2b3718f7f0be807e2870f8f47d3fa0796) !
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/ecc.h>
47 #include <kern/misc_protos.h>
48 #include <kern/startup.h>
49 #include <kern/clock.h>
50 #include <kern/debug.h>
51 #include <kern/processor.h>
52 #include <kdp/kdp_core.h>
53 #if ALTERNATE_DEBUGGER
54 #include <arm64/alternate_debugger.h>
55 #endif
56 #include <machine/atomic.h>
57 #include <machine/trap.h>
58 #include <kern/spl.h>
59 #include <pexpert/pexpert.h>
60 #include <kdp/kdp_callout.h>
61 #include <kdp/kdp_dyld.h>
62 #include <kdp/kdp_internal.h>
63 #include <kdp/kdp_common.h>
64 #include <uuid/uuid.h>
65 #include <sys/codesign.h>
66 #include <sys/time.h>
67 
68 #if CONFIG_SPTM
69 #include <kern/percpu.h>
70 #include <arm64/sptm/pmap/pmap_data.h>
71 #endif
72 
73 #include <IOKit/IOPlatformExpert.h>
74 #include <IOKit/IOKitServer.h>
75 
76 #include <mach/vm_prot.h>
77 #include <vm/vm_map_xnu.h>
78 #include <vm/pmap.h>
79 #include <vm/vm_shared_region.h>
80 #include <mach/time_value.h>
81 #include <machine/machparam.h>  /* for btop */
82 
83 #include <console/video_console.h>
84 #include <console/serial_protos.h>
85 #include <arm/cpu_data.h>
86 #include <arm/cpu_data_internal.h>
87 #include <arm/cpu_internal.h>
88 #include <arm/misc_protos.h>
89 #include <libkern/OSKextLibPrivate.h>
90 #include <vm/vm_kern.h>
91 #include <kern/kern_cdata.h>
92 #include <kern/ledger.h>
93 #include <san/kcov_ksancov.h>
94 
95 
96 #if DEVELOPMENT || DEBUG
97 #include <kern/ext_paniclog.h>
98 #endif
99 
100 #if CONFIG_EXCLAVES
101 #include <kern/exclaves_panic.h>
102 #include <kern/exclaves_inspection.h>
103 #endif
104 
105 
106 #if     MACH_KDP
107 void    kdp_trap(unsigned int, struct arm_saved_state *);
108 #endif
109 
110 /*
111  * Increment the PANICLOG_VERSION if you change the format of the panic
112  * log in any way.
113  */
114 #define PANICLOG_VERSION 15
115 static struct kcdata_descriptor kc_panic_data;
116 
117 extern char iBoot_version[];
118 #if defined(TARGET_OS_OSX) && defined(__arm64__)
119 extern char iBoot_Stage_2_version[];
120 #endif /* defined(TARGET_OS_OSX) && defined(__arm64__) */
121 
122 extern volatile uint32_t        debug_enabled;
123 extern unsigned int         not_in_kdp;
124 
125 extern int                              copyinframe(vm_address_t fp, uint32_t * frame);
126 extern void                             kdp_callouts(kdp_event_t event);
127 
128 #define MAX_PROCNAME_LEN 32
129 /* #include <sys/proc.h> */
130 struct proc;
131 extern int        proc_pid(struct proc *p);
132 extern void       proc_name_kdp(struct proc *, char *, int);
133 
134 /*
135  * Make sure there's enough space to include the relevant bits in the format required
136  * within the space allocated for the panic version string in the panic header.
137  * The format required by OSAnalytics/DumpPanic is 'Product Version (OS Version)'.
138  */
139 #define PANIC_HEADER_VERSION_FMT_STR "%.14s (%.14s)"
140 
141 extern const char version[];
142 extern char       osversion[];
143 extern char       osproductversion[];
144 extern char       osreleasetype[];
145 
146 #if defined(XNU_TARGET_OS_BRIDGE)
147 extern char     macosproductversion[];
148 extern char     macosversion[];
149 #endif
150 
151 extern uint8_t          gPlatformECID[8];
152 extern uint32_t         gPlatformMemoryID;
153 
154 extern uint64_t         last_hwaccess_thread;
155 extern uint8_t          last_hwaccess_type; /* 0 : read, 1 : write. */
156 extern uint8_t          last_hwaccess_size;
157 extern uint64_t         last_hwaccess_paddr;
158 
159 /*Choosing the size for gTargetTypeBuffer as 16 and size for gModelTypeBuffer as 32
160  *  since the target name and model name typically  doesn't exceed this size */
161 extern char  gTargetTypeBuffer[16];
162 extern char  gModelTypeBuffer[32];
163 
164 extern struct timeval    gIOLastSleepTime;
165 extern struct timeval    gIOLastWakeTime;
166 extern boolean_t                 is_clock_configured;
167 extern boolean_t kernelcache_uuid_valid;
168 extern uuid_t kernelcache_uuid;
169 extern uuid_string_t bootsessionuuid_string;
170 
171 extern uint64_t roots_installed;
172 
173 /* Definitions for frame pointers */
174 #define FP_ALIGNMENT_MASK      ((uint32_t)(0x3))
175 #define FP_LR_OFFSET           ((uint32_t)4)
176 #define FP_LR_OFFSET64         ((uint32_t)8)
177 #define FP_MAX_NUM_TO_EVALUATE (50)
178 
179 /* Timeout for all processors responding to debug crosscall */
180 MACHINE_TIMEOUT_ALWAYS_ENABLED(debug_ack_timeout, "debug-ack", 240000, MACHINE_TIMEOUT_UNIT_TIMEBASE);
181 
182 /* Forward functions definitions */
183 void panic_display_times(void);
184 void panic_print_symbol_name(vm_address_t search);
185 
186 
187 /* Global variables */
188 static uint32_t       panic_bt_depth;
189 boolean_t             PanicInfoSaved = FALSE;
190 boolean_t             force_immediate_debug_halt = FALSE;
191 unsigned int          debug_ack_timeout_count = 0;
192 _Atomic unsigned int  debugger_sync = 0;
193 _Atomic unsigned int  mp_kdp_trap = 0; /* CPUs signalled by the debug CPU will spin on this */
194 _Atomic unsigned int  debug_cpus_spinning = 0; /* Number of signalled CPUs still spinning on mp_kdp_trap (in DebuggerXCall). */
195 unsigned int          DebugContextCount = 0;
196 bool                  trap_is_stackshot = false; /* Whether the trap is for a stackshot */
197 
198 #if defined(__arm64__)
199 uint8_t PE_smc_stashed_x86_system_state = 0xFF;
200 uint8_t PE_smc_stashed_x86_power_state = 0xFF;
201 uint8_t PE_smc_stashed_x86_efi_boot_state = 0xFF;
202 uint8_t PE_smc_stashed_x86_shutdown_cause = 0xFF;
203 uint64_t PE_smc_stashed_x86_prev_power_transitions = UINT64_MAX;
204 uint32_t PE_pcie_stashed_link_state = UINT32_MAX;
205 uint64_t PE_nvram_stashed_x86_macos_slide = UINT64_MAX;
206 #endif
207 
208 
209 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)210 do_print_backtrace_internal(pmap_t pmap, vm_offset_t topfp, const char *cur_marker,
211     boolean_t is_64_bit, boolean_t print_kexts_in_backtrace)
212 {
213 	unsigned int    i = 0;
214 	addr64_t        lr = 0;
215 	addr64_t        fp = topfp;
216 	addr64_t        fp_for_ppn = 0;
217 	ppnum_t         ppn = (ppnum_t)NULL;
218 	vm_offset_t     raddrs[FP_MAX_NUM_TO_EVALUATE] = { 0 };
219 	bool            dump_kernel_stack = (fp >= VM_MIN_KERNEL_ADDRESS);
220 
221 	do {
222 		if ((fp == 0) || ((fp & FP_ALIGNMENT_MASK) != 0)) {
223 			break;
224 		}
225 
226 		if ((!dump_kernel_stack) && (fp >= VM_MIN_KERNEL_ADDRESS)) {
227 			break;
228 		}
229 
230 		/*
231 		 * Check to see if current address will result in a different
232 		 * ppn than previously computed (to avoid recomputation) via
233 		 * (addr) ^ fp_for_ppn) >> PAGE_SHIFT)
234 		 */
235 		if ((((fp + FP_LR_OFFSET) ^ fp_for_ppn) >> PAGE_SHIFT) != 0x0U) {
236 			ppn = pmap_find_phys(pmap, fp + FP_LR_OFFSET);
237 			fp_for_ppn = fp + (is_64_bit ? FP_LR_OFFSET64 : FP_LR_OFFSET);
238 		}
239 		if (ppn != (ppnum_t)NULL) {
240 			if (is_64_bit) {
241 				lr = ml_phys_read_double_64(((((vm_offset_t)ppn) << PAGE_SHIFT)) | ((fp + FP_LR_OFFSET64) & PAGE_MASK));
242 #if defined(HAS_APPLE_PAC)
243 				/* return addresses on stack will be signed by arm64e ABI */
244 				lr = (addr64_t) ptrauth_strip((void *)lr, ptrauth_key_return_address);
245 #endif
246 			} else {
247 				lr = ml_phys_read_word(((((vm_offset_t)ppn) << PAGE_SHIFT)) | ((fp + FP_LR_OFFSET) & PAGE_MASK));
248 			}
249 		} else {
250 			if (is_64_bit) {
251 				paniclog_append_noflush("%s\t  Could not read LR from frame at 0x%016llx\n", cur_marker, fp + FP_LR_OFFSET64);
252 			} else {
253 				paniclog_append_noflush("%s\t  Could not read LR from frame at 0x%08x\n", cur_marker, (uint32_t)(fp + FP_LR_OFFSET));
254 			}
255 			break;
256 		}
257 		if (((fp ^ fp_for_ppn) >> PAGE_SHIFT) != 0x0U) {
258 			ppn = pmap_find_phys(pmap, fp);
259 			fp_for_ppn = fp;
260 		}
261 		if (ppn != (ppnum_t)NULL) {
262 			if (is_64_bit) {
263 				fp = ml_phys_read_double_64(((((vm_offset_t)ppn) << PAGE_SHIFT)) | (fp & PAGE_MASK));
264 #if defined(HAS_APPLE_PAC)
265 				/* frame pointers on stack will be signed by arm64e ABI */
266 				fp = (addr64_t) ptrauth_strip((void *)fp, ptrauth_key_frame_pointer);
267 #endif
268 			} else {
269 				fp = ml_phys_read_word(((((vm_offset_t)ppn) << PAGE_SHIFT)) | (fp & PAGE_MASK));
270 			}
271 		} else {
272 			if (is_64_bit) {
273 				paniclog_append_noflush("%s\t  Could not read FP from frame at 0x%016llx\n", cur_marker, fp);
274 			} else {
275 				paniclog_append_noflush("%s\t  Could not read FP from frame at 0x%08x\n", cur_marker, (uint32_t)fp);
276 			}
277 			break;
278 		}
279 		/*
280 		 * Counter 'i' may == FP_MAX_NUM_TO_EVALUATE when running one
281 		 * extra round to check whether we have all frames in order to
282 		 * indicate (in)complete backtrace below. This happens in a case
283 		 * where total frame count and FP_MAX_NUM_TO_EVALUATE are equal.
284 		 * Do not capture anything.
285 		 */
286 		if (i < FP_MAX_NUM_TO_EVALUATE && lr) {
287 			if (is_64_bit) {
288 				paniclog_append_noflush("%s\t  lr: 0x%016llx  fp: 0x%016llx\n", cur_marker, lr, fp);
289 			} else {
290 				paniclog_append_noflush("%s\t  lr: 0x%08x  fp: 0x%08x\n", cur_marker, (uint32_t)lr, (uint32_t)fp);
291 			}
292 			raddrs[i] = lr;
293 		}
294 	} while ((++i <= FP_MAX_NUM_TO_EVALUATE) && (fp != topfp));
295 
296 	if (i > FP_MAX_NUM_TO_EVALUATE && fp != 0) {
297 		paniclog_append_noflush("Backtrace continues...\n");
298 	}
299 
300 	if (print_kexts_in_backtrace && i > 0) {
301 		kmod_panic_dump(&raddrs[0], i);
302 	}
303 }
304 
305 #define SANE_TASK_LIMIT 256
306 #define TOP_RUNNABLE_LIMIT 5
307 #define PANICLOG_UUID_BUF_SIZE 256
308 
309 extern void panic_print_vnodes(void);
310 
311 static void
panic_display_tpidrs(void)312 panic_display_tpidrs(void)
313 {
314 #if defined(__arm64__)
315 	paniclog_append_noflush("TPIDRx_ELy = {1: 0x%016llx  0: 0x%016llx  0ro: 0x%016llx }\n",
316 	    __builtin_arm_rsr64("TPIDR_EL1"), __builtin_arm_rsr64("TPIDR_EL0"),
317 	    __builtin_arm_rsr64("TPIDRRO_EL0"));
318 #endif //defined(__arm64__)
319 }
320 
321 
322 
323 static void
panic_display_hung_cpus_help(void)324 panic_display_hung_cpus_help(void)
325 {
326 #if defined(__arm64__)
327 	const uint32_t pcsr_offset = 0x90;
328 
329 	/*
330 	 * Print some info that might help in cases where nothing
331 	 * else does
332 	 */
333 	const ml_topology_info_t *info = ml_get_topology_info();
334 	if (info) {
335 		unsigned i, retry;
336 
337 		for (i = 0; i < info->num_cpus; i++) {
338 			ml_topology_cpu_t *cpu = &info->cpus[i];
339 			char cluster_name[16], cluster_letter;
340 
341 			switch (cpu->cluster_type) {
342 			case CLUSTER_TYPE_E:
343 				cluster_letter = 'E';
344 				break;
345 			case CLUSTER_TYPE_P:
346 				cluster_letter = 'P';
347 				break;
348 			default:
349 				cluster_letter = '?';
350 			}
351 			snprintf(cluster_name, sizeof(cluster_name), "%cACC%d", cluster_letter, cpu->cluster_id);
352 
353 			if (!PE_cpu_power_check_kdp(i)) {
354 				paniclog_append_noflush("CORE %u [%s] is offline, skipping\n", i, cluster_name);
355 				continue;
356 			}
357 			if (cpu->cpu_UTTDBG_regs) {
358 				volatile uint64_t *pcsr = (volatile uint64_t*)(cpu->cpu_UTTDBG_regs + pcsr_offset);
359 				volatile uint32_t *pcsrTrigger = (volatile uint32_t*)pcsr;
360 				uint64_t pc = 0;
361 
362 				// a number of retries are needed till this works
363 				for (retry = 1024; retry && !pc; retry--) {
364 					//a 32-bit read is required to make a PC sample be produced, else we'll only get a zero
365 					(void)*pcsrTrigger;
366 					pc = *pcsr;
367 				}
368 
369 				//postprocessing (same as astris does)
370 				if (pc >> 48) {
371 					pc |= 0xffff000000000000ull;
372 				}
373 				paniclog_append_noflush("CORE %u [%s] recently retired instr at 0x%016llx\n", i, cluster_name, pc);
374 			}
375 		}
376 	}
377 #endif //defined(__arm64__)
378 }
379 
380 
381 
382 static void
panic_display_pvhs_locked(void)383 panic_display_pvhs_locked(void)
384 {
385 }
386 
387 static void
panic_display_pvh_to_lock(void)388 panic_display_pvh_to_lock(void)
389 {
390 }
391 
392 static void
panic_display_last_pc_lr(void)393 panic_display_last_pc_lr(void)
394 {
395 #if defined(__arm64__)
396 	const int max_cpu = ml_get_max_cpu_number();
397 
398 	for (int cpu = 0; cpu <= max_cpu; cpu++) {
399 		cpu_data_t *current_cpu_datap = cpu_datap(cpu);
400 
401 		if (current_cpu_datap == NULL) {
402 			continue;
403 		}
404 
405 		if (current_cpu_datap == getCpuDatap()) {
406 			/**
407 			 * Skip printing the PC/LR if this is the CPU
408 			 * that initiated the panic.
409 			 */
410 			paniclog_append_noflush("CORE %u is the one that panicked. Check the full backtrace for details.\n", cpu);
411 			continue;
412 		}
413 
414 		paniclog_append_noflush("CORE %u: PC=0x%016llx, LR=0x%016llx, FP=0x%016llx\n", cpu,
415 		    current_cpu_datap->ipi_pc, (uint64_t)VM_KERNEL_STRIP_PTR(current_cpu_datap->ipi_lr),
416 		    (uint64_t)VM_KERNEL_STRIP_PTR(current_cpu_datap->ipi_fp));
417 	}
418 #endif
419 }
420 
421 #if CONFIG_EXCLAVES
422 static void
panic_report_exclaves_stackshot(void)423 panic_report_exclaves_stackshot(void)
424 {
425 	if (exclaves_panic_ss_status == EXCLAVES_PANIC_STACKSHOT_FOUND) {
426 		paniclog_append_noflush("** Exclaves panic stackshot found\n");
427 	} else if (exclaves_panic_ss_status == EXCLAVES_PANIC_STACKSHOT_NOT_FOUND) {
428 		paniclog_append_noflush("** Exclaves panic stackshot not found\n");
429 	} else if (exclaves_panic_ss_status == EXCLAVES_PANIC_STACKSHOT_DECODE_FAILED) {
430 		paniclog_append_noflush("!! Exclaves panic stackshot decode failed !!\n");
431 	}
432 }
433 #endif /* CONFIG_EXCLAVES */
434 
435 __attribute__((always_inline))
436 static inline void
print_backtrace_internal(thread_t thread,bool filesetKC)437 print_backtrace_internal(thread_t thread, bool filesetKC)
438 {
439 	uintptr_t cur_fp = (uintptr_t)__builtin_frame_address(0);
440 	const char              *nohilite_thread_marker = "\t";
441 
442 #if defined(HAS_APPLE_PAC)
443 	cur_fp = (addr64_t)ptrauth_strip((void *)cur_fp, ptrauth_key_frame_pointer);
444 #endif
445 
446 	if (cur_fp < VM_MAX_KERNEL_ADDRESS) {
447 		paniclog_append_noflush("Panicked thread: %p, backtrace: 0x%llx, tid: %llu\n",
448 		    thread, (addr64_t)cur_fp, thread_tid(thread));
449 #if __LP64__
450 		do_print_backtrace_internal(kernel_pmap, cur_fp, nohilite_thread_marker, TRUE, filesetKC);
451 #else
452 		do_print_backtrace_internal(kernel_pmap, cur_fp, nohilite_thread_marker, FALSE, filesetKC);
453 #endif
454 	} else {
455 		paniclog_append_noflush("Could not print panicked thread backtrace:"
456 		    "frame pointer outside kernel vm.\n");
457 	}
458 }
459 
460 static bool
is_filesetKC(void)461 is_filesetKC(void)
462 {
463 	kc_format_t     kc_format;
464 	bool            filesetKC = false;
465 
466 	__unused bool result = PE_get_primary_kc_format(&kc_format);
467 	assert(result == true);
468 	filesetKC = kc_format == KCFormatFileset;
469 	return filesetKC;
470 }
471 
472 
473 static void
do_print_all_panic_info(const char * message,uint64_t panic_options,const char * panic_initiator)474 do_print_all_panic_info(const char *message, uint64_t panic_options, const char *panic_initiator)
475 {
476 	int             logversion = PANICLOG_VERSION;
477 	thread_t        cur_thread = current_thread();
478 	task_t          task;
479 	struct proc    *proc;
480 	int             print_vnodes = 0;
481 
482 	/* end_marker_bytes set to 200 for printing END marker + stackshot summary info always */
483 	int bytes_traced = 0, bytes_remaining = 0, end_marker_bytes = 200;
484 	int bytes_uncompressed = 0;
485 	uint64_t bytes_used = 0ULL;
486 	int err = 0;
487 	char *stackshot_begin_loc = NULL;
488 	bool filesetKC = is_filesetKC();
489 	uint32_t panic_initiator_len = 0;
490 #if CONFIG_EXT_PANICLOG
491 	uint32_t ext_paniclog_bytes = 0;
492 #endif
493 
494 	if (panic_bt_depth != 0) {
495 		return;
496 	}
497 	panic_bt_depth++;
498 
499 	/* Truncate panic string to 1200 bytes */
500 	paniclog_append_noflush("Debugger message: %.1200s\n", message);
501 	if (debug_enabled) {
502 		paniclog_append_noflush("Device: %s\n",
503 		    ('\0' != gTargetTypeBuffer[0]) ? gTargetTypeBuffer : "Not set yet");
504 		paniclog_append_noflush("Hardware Model: %s\n",
505 		    ('\0' != gModelTypeBuffer[0]) ? gModelTypeBuffer:"Not set yet");
506 		paniclog_append_noflush("ECID: %02X%02X%02X%02X%02X%02X%02X%02X\n", gPlatformECID[7],
507 		    gPlatformECID[6], gPlatformECID[5], gPlatformECID[4], gPlatformECID[3],
508 		    gPlatformECID[2], gPlatformECID[1], gPlatformECID[0]);
509 		if (last_hwaccess_thread) {
510 			paniclog_append_noflush("AppleHWAccess Thread: 0x%llx\n", last_hwaccess_thread);
511 			if (!last_hwaccess_size) {
512 				paniclog_append_noflush("AppleHWAccess last access: no access data, this is unexpected.\n");
513 			} else {
514 				const char *typ = last_hwaccess_type ? "write" : "read";
515 				paniclog_append_noflush("AppleHWAccess last access: %s of size %u at address 0x%llx\n", typ, last_hwaccess_size, last_hwaccess_paddr);
516 			}
517 		}
518 		paniclog_append_noflush("Boot args: %s\n", PE_boot_args());
519 	}
520 	paniclog_append_noflush("Memory ID: 0x%x\n", gPlatformMemoryID);
521 	paniclog_append_noflush("OS release type: %.256s\n",
522 	    ('\0' != osreleasetype[0]) ? osreleasetype : "Not set yet");
523 	paniclog_append_noflush("OS version: %.256s\n",
524 	    ('\0' != osversion[0]) ? osversion : "Not set yet");
525 #if defined(XNU_TARGET_OS_BRIDGE)
526 	paniclog_append_noflush("macOS version: %.256s\n",
527 	    ('\0' != macosversion[0]) ? macosversion : "Not set");
528 #endif
529 	paniclog_append_noflush("Kernel version: %.512s\n", version);
530 
531 #if CONFIG_EXCLAVES
532 	exclaves_panic_append_info();
533 #endif
534 
535 	if (kernelcache_uuid_valid) {
536 		if (filesetKC) {
537 			paniclog_append_noflush("Fileset Kernelcache UUID: ");
538 		} else {
539 			paniclog_append_noflush("KernelCache UUID: ");
540 		}
541 		for (size_t index = 0; index < sizeof(uuid_t); index++) {
542 			paniclog_append_noflush("%02X", kernelcache_uuid[index]);
543 		}
544 		paniclog_append_noflush("\n");
545 	}
546 	panic_display_kernel_uuid();
547 
548 	if (bootsessionuuid_string[0] != '\0') {
549 		paniclog_append_noflush("Boot session UUID: %s\n", bootsessionuuid_string);
550 	} else {
551 		paniclog_append_noflush("Boot session UUID not yet initialized\n");
552 	}
553 
554 	paniclog_append_noflush("iBoot version: %.128s\n", iBoot_version);
555 #if defined(TARGET_OS_OSX) && defined(__arm64__)
556 	paniclog_append_noflush("iBoot Stage 2 version: %.128s\n", iBoot_Stage_2_version);
557 #endif /* defined(TARGET_OS_OSX) && defined(__arm64__) */
558 
559 	paniclog_append_noflush("secure boot?: %s\n", debug_enabled ? "NO": "YES");
560 	paniclog_append_noflush("roots installed: %lld\n", roots_installed);
561 #if defined(XNU_TARGET_OS_BRIDGE)
562 	paniclog_append_noflush("x86 EFI Boot State: ");
563 	if (PE_smc_stashed_x86_efi_boot_state != 0xFF) {
564 		paniclog_append_noflush("0x%x\n", PE_smc_stashed_x86_efi_boot_state);
565 	} else {
566 		paniclog_append_noflush("not available\n");
567 	}
568 	paniclog_append_noflush("x86 System State: ");
569 	if (PE_smc_stashed_x86_system_state != 0xFF) {
570 		paniclog_append_noflush("0x%x\n", PE_smc_stashed_x86_system_state);
571 	} else {
572 		paniclog_append_noflush("not available\n");
573 	}
574 	paniclog_append_noflush("x86 Power State: ");
575 	if (PE_smc_stashed_x86_power_state != 0xFF) {
576 		paniclog_append_noflush("0x%x\n", PE_smc_stashed_x86_power_state);
577 	} else {
578 		paniclog_append_noflush("not available\n");
579 	}
580 	paniclog_append_noflush("x86 Shutdown Cause: ");
581 	if (PE_smc_stashed_x86_shutdown_cause != 0xFF) {
582 		paniclog_append_noflush("0x%x\n", PE_smc_stashed_x86_shutdown_cause);
583 	} else {
584 		paniclog_append_noflush("not available\n");
585 	}
586 	paniclog_append_noflush("x86 Previous Power Transitions: ");
587 	if (PE_smc_stashed_x86_prev_power_transitions != UINT64_MAX) {
588 		paniclog_append_noflush("0x%llx\n", PE_smc_stashed_x86_prev_power_transitions);
589 	} else {
590 		paniclog_append_noflush("not available\n");
591 	}
592 	paniclog_append_noflush("PCIeUp link state: ");
593 	if (PE_pcie_stashed_link_state != UINT32_MAX) {
594 		paniclog_append_noflush("0x%x\n", PE_pcie_stashed_link_state);
595 	} else {
596 		paniclog_append_noflush("not available\n");
597 	}
598 	paniclog_append_noflush("macOS kernel slide: ");
599 	if (PE_nvram_stashed_x86_macos_slide != UINT64_MAX) {
600 		paniclog_append_noflush("%#llx\n", PE_nvram_stashed_x86_macos_slide);
601 	} else {
602 		paniclog_append_noflush("not available\n");
603 	}
604 #endif
605 	if (panic_data_buffers != NULL) {
606 		paniclog_append_noflush("%s data: ", panic_data_buffers->producer_name);
607 		uint8_t *panic_buffer_data = (uint8_t *) panic_data_buffers->buf;
608 		for (int i = 0; i < panic_data_buffers->len; i++) {
609 			paniclog_append_noflush("%02X", panic_buffer_data[i]);
610 		}
611 		paniclog_append_noflush("\n");
612 	}
613 	paniclog_append_noflush("Paniclog version: %d\n", logversion);
614 
615 	panic_display_kernel_aslr();
616 	panic_display_times();
617 	panic_display_zalloc();
618 	panic_display_hung_cpus_help();
619 	panic_display_tpidrs();
620 
621 
622 	panic_display_pvhs_locked();
623 	panic_display_pvh_to_lock();
624 	panic_display_last_pc_lr();
625 #if CONFIG_ECC_LOGGING
626 	panic_display_ecc_errors();
627 #endif /* CONFIG_ECC_LOGGING */
628 	panic_display_compressor_stats();
629 
630 #if DEVELOPMENT || DEBUG
631 	if (cs_debug_unsigned_exec_failures != 0 || cs_debug_unsigned_mmap_failures != 0) {
632 		paniclog_append_noflush("Unsigned code exec failures: %u\n", cs_debug_unsigned_exec_failures);
633 		paniclog_append_noflush("Unsigned code mmap failures: %u\n", cs_debug_unsigned_mmap_failures);
634 	}
635 #endif
636 
637 	// Highlight threads that used high amounts of CPU in the panic log if requested (historically requested for watchdog panics)
638 	if (panic_options & DEBUGGER_OPTION_PRINT_CPU_USAGE_PANICLOG) {
639 		thread_t        top_runnable[5] = {0};
640 		thread_t        thread;
641 		int                     total_cpu_usage = 0;
642 
643 		print_vnodes = 1;
644 
645 
646 		for (thread = (thread_t)queue_first(&threads);
647 		    PANIC_VALIDATE_PTR(thread) && !queue_end(&threads, (queue_entry_t)thread);
648 		    thread = (thread_t)queue_next(&thread->threads)) {
649 			total_cpu_usage += thread->cpu_usage;
650 
651 			// Look for the 5 runnable threads with highest priority
652 			if (thread->state & TH_RUN) {
653 				int                     k;
654 				thread_t        comparison_thread = thread;
655 
656 				for (k = 0; k < TOP_RUNNABLE_LIMIT; k++) {
657 					if (top_runnable[k] == 0) {
658 						top_runnable[k] = comparison_thread;
659 						break;
660 					} else if (comparison_thread->sched_pri > top_runnable[k]->sched_pri) {
661 						thread_t temp = top_runnable[k];
662 						top_runnable[k] = comparison_thread;
663 						comparison_thread = temp;
664 					} // if comparison thread has higher priority than previously saved thread
665 				} // loop through highest priority runnable threads
666 			} // Check if thread is runnable
667 		} // Loop through all threads
668 
669 		// Print the relevant info for each thread identified
670 		paniclog_append_noflush("Total cpu_usage: %d\n", total_cpu_usage);
671 		paniclog_append_noflush("Thread task pri cpu_usage\n");
672 
673 		for (int i = 0; i < TOP_RUNNABLE_LIMIT; i++) {
674 			if (top_runnable[i] &&
675 			    panic_get_thread_proc_task(top_runnable[i], &task, &proc) && proc) {
676 				char name[MAX_PROCNAME_LEN + 1];
677 				proc_name_kdp(proc, name, sizeof(name));
678 				paniclog_append_noflush("%p %s %d %d\n",
679 				    top_runnable[i], name, top_runnable[i]->sched_pri, top_runnable[i]->cpu_usage);
680 			}
681 		} // Loop through highest priority runnable threads
682 		paniclog_append_noflush("\n");
683 	}
684 
685 	// print current task info
686 	if (panic_get_thread_proc_task(cur_thread, &task, &proc)) {
687 		if (PANIC_VALIDATE_PTR(task->map) &&
688 		    PANIC_VALIDATE_PTR(task->map->pmap)) {
689 			ledger_amount_t resident = 0;
690 			if (task != kernel_task) {
691 				ledger_get_balance(task->ledger, task_ledgers.phys_mem, &resident);
692 				resident >>= VM_MAP_PAGE_SHIFT(task->map);
693 			}
694 			paniclog_append_noflush("Panicked task %p: %lld pages, %d threads: ",
695 			    task, resident, task->thread_count);
696 		} else {
697 			paniclog_append_noflush("Panicked task %p: %d threads: ",
698 			    task, task->thread_count);
699 		}
700 
701 		if (proc) {
702 			char            name[MAX_PROCNAME_LEN + 1];
703 			proc_name_kdp(proc, name, sizeof(name));
704 			paniclog_append_noflush("pid %d: %s", proc_pid(proc), name);
705 		} else {
706 			paniclog_append_noflush("unknown task");
707 		}
708 
709 		paniclog_append_noflush("\n");
710 	}
711 
712 	print_backtrace_internal(cur_thread, filesetKC);
713 
714 	paniclog_append_noflush("\n");
715 	dump_cpu_event_log(&paniclog_append_noflush);
716 
717 	paniclog_append_noflush("\n");
718 	if (filesetKC) {
719 		kext_dump_panic_lists(&paniclog_append_noflush);
720 		paniclog_append_noflush("\n");
721 	}
722 	panic_info->eph_panic_log_len = PE_get_offset_into_panic_region(debug_buf_ptr) - panic_info->eph_panic_log_offset;
723 	/* set the os version data in the panic header in the format 'Product Version (OS Version)' (only if they have been set) */
724 	if ((osversion[0] != '\0') && (osproductversion[0] != '\0')) {
725 		snprintf((char *)&panic_info->eph_os_version, sizeof(panic_info->eph_os_version), PANIC_HEADER_VERSION_FMT_STR,
726 		    osproductversion, osversion);
727 	}
728 #if defined(XNU_TARGET_OS_BRIDGE)
729 	if ((macosversion[0] != '\0') && (macosproductversion[0] != '\0')) {
730 		snprintf((char *)&panic_info->eph_macos_version, sizeof(panic_info->eph_macos_version), PANIC_HEADER_VERSION_FMT_STR,
731 		    macosproductversion, macosversion);
732 	}
733 #endif
734 	if (bootsessionuuid_string[0] != '\0') {
735 		memcpy(panic_info->eph_bootsessionuuid_string, bootsessionuuid_string,
736 		    sizeof(panic_info->eph_bootsessionuuid_string));
737 	}
738 	panic_info->eph_roots_installed = roots_installed;
739 
740 	if (panic_initiator != NULL) {
741 		bytes_remaining = debug_buf_size - (unsigned int)((uintptr_t)debug_buf_ptr - (uintptr_t)debug_buf_base);
742 		// If panic_initiator isn't null, safely copy up to MAX_PANIC_INITIATOR_SIZE
743 		panic_initiator_len = strnlen(panic_initiator, MAX_PANIC_INITIATOR_SIZE);
744 		// Calculate the bytes to write, accounting for remaining buffer space, and ensuring the lowest size we can have is 0
745 		panic_initiator_len = MAX(0, MIN(panic_initiator_len, bytes_remaining));
746 		panic_info->eph_panic_initiator_offset = (panic_initiator_len != 0) ? PE_get_offset_into_panic_region(debug_buf_ptr) : 0;
747 		panic_info->eph_panic_initiator_len = panic_initiator_len;
748 		memcpy(debug_buf_ptr, panic_initiator, panic_initiator_len);
749 		debug_buf_ptr += panic_initiator_len;
750 	}
751 
752 	if (debug_ack_timeout_count) {
753 		panic_info->eph_panic_flags |= EMBEDDED_PANIC_HEADER_FLAG_STACKSHOT_FAILED_DEBUGGERSYNC;
754 		panic_info->eph_other_log_offset = PE_get_offset_into_panic_region(debug_buf_ptr);
755 		paniclog_append_noflush("!! debugger synchronization failed, no stackshot !!\n");
756 	} else if (panic_stackshot_active()) {
757 		panic_info->eph_panic_flags |= EMBEDDED_PANIC_HEADER_FLAG_STACKSHOT_FAILED_NESTED;
758 		panic_info->eph_other_log_offset = PE_get_offset_into_panic_region(debug_buf_ptr);
759 		paniclog_append_noflush("!! panicked during stackshot, skipping panic stackshot !!\n");
760 	} else {
761 		/* Align the stackshot buffer to an 8-byte address (especially important for armv7k devices) */
762 		debug_buf_ptr += (8 - ((uintptr_t)debug_buf_ptr % 8));
763 		stackshot_begin_loc = debug_buf_ptr;
764 
765 		bytes_remaining = debug_buf_size - (unsigned int)((uintptr_t)stackshot_begin_loc - (uintptr_t)debug_buf_base);
766 		err = kcdata_memory_static_init(&kc_panic_data, (mach_vm_address_t)debug_buf_ptr,
767 		    KCDATA_BUFFER_BEGIN_COMPRESSED, bytes_remaining - end_marker_bytes,
768 		    KCFLAG_USE_MEMCOPY);
769 		if (err == KERN_SUCCESS) {
770 			uint64_t stackshot_flags = (STACKSHOT_GET_GLOBAL_MEM_STATS | STACKSHOT_SAVE_LOADINFO | STACKSHOT_KCDATA_FORMAT |
771 			    STACKSHOT_ENABLE_BT_FAULTING | STACKSHOT_ENABLE_UUID_FAULTING | STACKSHOT_FROM_PANIC | STACKSHOT_DO_COMPRESS |
772 			    STACKSHOT_DISABLE_LATENCY_INFO | STACKSHOT_NO_IO_STATS | STACKSHOT_THREAD_WAITINFO | STACKSHOT_GET_DQ |
773 			    STACKSHOT_COLLECT_SHAREDCACHE_LAYOUT);
774 
775 			err = kcdata_init_compress(&kc_panic_data, KCDATA_BUFFER_BEGIN_STACKSHOT, kdp_memcpy, KCDCT_ZLIB);
776 			if (err != KERN_SUCCESS) {
777 				panic_info->eph_panic_flags |= EMBEDDED_PANIC_HEADER_FLAG_COMPRESS_FAILED;
778 				stackshot_flags &= ~STACKSHOT_DO_COMPRESS;
779 			}
780 			if (filesetKC) {
781 				stackshot_flags |= STACKSHOT_SAVE_KEXT_LOADINFO;
782 			}
783 
784 			kdp_snapshot_preflight(-1, stackshot_begin_loc, bytes_remaining - end_marker_bytes,
785 			    stackshot_flags, &kc_panic_data, 0, 0);
786 			err = do_panic_stackshot(NULL);
787 			bytes_traced = kdp_stack_snapshot_bytes_traced();
788 			if (bytes_traced > 0 && !err) {
789 				debug_buf_ptr += bytes_traced;
790 				panic_info->eph_panic_flags |= EMBEDDED_PANIC_HEADER_FLAG_STACKSHOT_SUCCEEDED;
791 				panic_info->eph_stackshot_offset = PE_get_offset_into_panic_region(stackshot_begin_loc);
792 				panic_info->eph_stackshot_len = bytes_traced;
793 
794 				panic_info->eph_other_log_offset = PE_get_offset_into_panic_region(debug_buf_ptr);
795 #if CONFIG_EXCLAVES
796 				panic_report_exclaves_stackshot();
797 #endif /* CONFIG_EXCLAVES */
798 				if (stackshot_flags & STACKSHOT_DO_COMPRESS) {
799 					panic_info->eph_panic_flags |= EMBEDDED_PANIC_HEADER_FLAG_STACKSHOT_DATA_COMPRESSED;
800 					bytes_uncompressed = kdp_stack_snapshot_bytes_uncompressed();
801 					paniclog_append_noflush("\n** Stackshot Succeeded ** Bytes Traced %d (Uncompressed %d) **\n", bytes_traced, bytes_uncompressed);
802 				} else {
803 					paniclog_append_noflush("\n** Stackshot Succeeded ** Bytes Traced %d **\n", bytes_traced);
804 				}
805 			} else {
806 				bytes_used = kcdata_memory_get_used_bytes(&kc_panic_data);
807 #if CONFIG_EXCLAVES
808 				panic_report_exclaves_stackshot();
809 #endif /* CONFIG_EXCLAVES */
810 				if (bytes_used > 0) {
811 					/* Zero out the stackshot data */
812 					bzero(stackshot_begin_loc, bytes_used);
813 					panic_info->eph_panic_flags |= EMBEDDED_PANIC_HEADER_FLAG_STACKSHOT_FAILED_INCOMPLETE;
814 
815 					panic_info->eph_other_log_offset = PE_get_offset_into_panic_region(debug_buf_ptr);
816 					paniclog_append_noflush("\n** Stackshot Incomplete ** Bytes Filled %llu, err %d **\n", bytes_used, err);
817 				} else {
818 					bzero(stackshot_begin_loc, bytes_used);
819 					panic_info->eph_panic_flags |= EMBEDDED_PANIC_HEADER_FLAG_STACKSHOT_FAILED_ERROR;
820 
821 					panic_info->eph_other_log_offset = PE_get_offset_into_panic_region(debug_buf_ptr);
822 					paniclog_append_noflush("\n!! Stackshot Failed !! Bytes Traced %d, err %d\n", bytes_traced, err);
823 				}
824 			}
825 		} else {
826 			panic_info->eph_panic_flags |= EMBEDDED_PANIC_HEADER_FLAG_STACKSHOT_FAILED_ERROR;
827 			panic_info->eph_other_log_offset = PE_get_offset_into_panic_region(debug_buf_ptr);
828 			paniclog_append_noflush("\n!! Stackshot Failed !!\nkcdata_memory_static_init returned %d", err);
829 		}
830 	}
831 
832 	ksancov_on_panic_log();
833 
834 #if CONFIG_EXT_PANICLOG
835 	// Write ext paniclog at the end of the paniclog region.
836 	ext_paniclog_bytes = ext_paniclog_write_panicdata();
837 	panic_info->eph_ext_paniclog_offset = (ext_paniclog_bytes != 0) ?
838 	    PE_get_offset_into_panic_region((debug_buf_base + debug_buf_size) - ext_paniclog_bytes) :
839 	    0;
840 	panic_info->eph_ext_paniclog_len = ext_paniclog_bytes;
841 #endif
842 
843 	assert(panic_info->eph_other_log_offset != 0);
844 
845 	if (print_vnodes != 0) {
846 		panic_print_vnodes();
847 	}
848 
849 	panic_bt_depth--;
850 }
851 
852 /*
853  * Entry to print_all_panic_info is serialized by the debugger lock
854  */
855 static void
print_all_panic_info(const char * message,uint64_t panic_options,const char * panic_initiator)856 print_all_panic_info(const char *message, uint64_t panic_options, const char *panic_initiator)
857 {
858 	unsigned int initial_not_in_kdp = not_in_kdp;
859 
860 	cpu_data_t * cpu_data_ptr = getCpuDatap();
861 
862 	assert(cpu_data_ptr->PAB_active == FALSE);
863 	cpu_data_ptr->PAB_active = TRUE;
864 
865 	/*
866 	 * Because print all backtraces uses the pmap routines, it needs to
867 	 * avoid taking pmap locks.  Right now, this is conditionalized on
868 	 * not_in_kdp.
869 	 */
870 	not_in_kdp = 0;
871 	do_print_all_panic_info(message, panic_options, panic_initiator);
872 
873 	not_in_kdp = initial_not_in_kdp;
874 
875 	cpu_data_ptr->PAB_active = FALSE;
876 }
877 
878 void
print_curr_backtrace(void)879 print_curr_backtrace(void)
880 {
881 	print_backtrace_internal(current_thread(), is_filesetKC());
882 }
883 
884 void
panic_display_times()885 panic_display_times()
886 {
887 	if (kdp_clock_is_locked()) {
888 		paniclog_append_noflush("Warning: clock is locked.  Can't get time\n");
889 		return;
890 	}
891 
892 	extern lck_ticket_t clock_lock;
893 	extern lck_grp_t clock_lock_grp;
894 
895 	if ((is_clock_configured) && (lck_ticket_lock_try(&clock_lock, &clock_lock_grp))) {
896 		clock_sec_t     secs, boot_secs;
897 		clock_usec_t    usecs, boot_usecs;
898 
899 		lck_ticket_unlock(&clock_lock);
900 
901 		clock_get_calendar_microtime(&secs, &usecs);
902 		clock_get_boottime_microtime(&boot_secs, &boot_usecs);
903 
904 		paniclog_append_noflush("mach_absolute_time: 0x%llx\n", mach_absolute_time());
905 		paniclog_append_noflush("Epoch Time:        sec       usec\n");
906 		paniclog_append_noflush("  Boot    : 0x%08x 0x%08x\n", (unsigned int)boot_secs, (unsigned int)boot_usecs);
907 		paniclog_append_noflush("  Sleep   : 0x%08x 0x%08x\n", (unsigned int)gIOLastSleepTime.tv_sec, (unsigned int)gIOLastSleepTime.tv_usec);
908 		paniclog_append_noflush("  Wake    : 0x%08x 0x%08x\n", (unsigned int)gIOLastWakeTime.tv_sec, (unsigned int)gIOLastWakeTime.tv_usec);
909 		paniclog_append_noflush("  Calendar: 0x%08x 0x%08x\n\n", (unsigned int)secs, (unsigned int)usecs);
910 	}
911 }
912 
913 void
panic_print_symbol_name(vm_address_t search)914 panic_print_symbol_name(vm_address_t search)
915 {
916 #pragma unused(search)
917 	// empty stub. Really only used on x86_64.
918 	return;
919 }
920 
921 void
SavePanicInfo(const char * message,__unused void * panic_data,uint64_t panic_options,const char * panic_initiator)922 SavePanicInfo(
923 	const char *message, __unused void *panic_data, uint64_t panic_options, const char* panic_initiator)
924 {
925 	/*
926 	 * This should be initialized by the time we get here, but
927 	 * if it is not, asserting about it will be of no use (it will
928 	 * come right back to here), so just loop right here and now.
929 	 * This prevents early-boot panics from becoming recursive and
930 	 * thus makes them easier to debug. If you attached to a device
931 	 * and see your PC here, look down a few frames to see your
932 	 * early-boot panic there.
933 	 */
934 	while (!panic_info || panic_info->eph_panic_log_offset == 0) {
935 		// rdar://87170225 (PanicHardening: audit panic code for naked spinloops)
936 		// rdar://88094367 (Add test hooks for panic at different stages in XNU)
937 		;
938 	}
939 
940 	if (panic_options & DEBUGGER_OPTION_PANICLOGANDREBOOT) {
941 		panic_info->eph_panic_flags  |= EMBEDDED_PANIC_HEADER_FLAG_BUTTON_RESET_PANIC;
942 	}
943 
944 	if (panic_options & DEBUGGER_OPTION_COMPANION_PROC_INITIATED_PANIC) {
945 		panic_info->eph_panic_flags |= EMBEDDED_PANIC_HEADER_FLAG_COMPANION_PROC_INITIATED_PANIC;
946 	}
947 
948 	if (panic_options & DEBUGGER_OPTION_INTEGRATED_COPROC_INITIATED_PANIC) {
949 		panic_info->eph_panic_flags |= EMBEDDED_PANIC_HEADER_FLAG_INTEGRATED_COPROC_INITIATED_PANIC;
950 	}
951 
952 	if (panic_options & DEBUGGER_OPTION_USERSPACE_INITIATED_PANIC) {
953 		panic_info->eph_panic_flags |= EMBEDDED_PANIC_HEADER_FLAG_USERSPACE_INITIATED_PANIC;
954 	}
955 
956 #if defined(XNU_TARGET_OS_BRIDGE)
957 	panic_info->eph_x86_power_state = PE_smc_stashed_x86_power_state;
958 	panic_info->eph_x86_efi_boot_state = PE_smc_stashed_x86_efi_boot_state;
959 	panic_info->eph_x86_system_state = PE_smc_stashed_x86_system_state;
960 #endif
961 
962 	/*
963 	 * On newer targets, panic data is stored directly into the iBoot panic region.
964 	 * If we re-enter SavePanicInfo (e.g. on a double panic) on such a target, update the
965 	 * panic CRC so that iBoot can hopefully find *something* useful in the panic region.
966 	 */
967 	if (PanicInfoSaved && (debug_buf_base >= (char*)gPanicBase) && (debug_buf_base < (char*)gPanicBase + gPanicSize)) {
968 		unsigned int pi_size = (unsigned int)(debug_buf_ptr - gPanicBase);
969 		PE_update_panic_crc((unsigned char*)gPanicBase, &pi_size);
970 		PE_sync_panic_buffers(); // extra precaution; panic path likely isn't reliable if we're here
971 	}
972 
973 	if (PanicInfoSaved || (debug_buf_size == 0)) {
974 		return;
975 	}
976 
977 	PanicInfoSaved = TRUE;
978 
979 
980 	print_all_panic_info(message, panic_options, panic_initiator);
981 
982 	assert(panic_info->eph_panic_log_len != 0);
983 	panic_info->eph_other_log_len = PE_get_offset_into_panic_region(debug_buf_ptr) - panic_info->eph_other_log_offset;
984 
985 	PEHaltRestart(kPEPanicSync);
986 
987 	/*
988 	 * Notifies registered IOPlatformPanicAction callbacks
989 	 * (which includes one to disable the memcache) and flushes
990 	 * the buffer contents from the cache
991 	 */
992 	paniclog_flush();
993 }
994 
995 void
paniclog_flush()996 paniclog_flush()
997 {
998 	unsigned int panicbuf_length = 0;
999 
1000 	panicbuf_length = (unsigned int)(debug_buf_ptr - gPanicBase);
1001 	if (!debug_buf_ptr || !panicbuf_length) {
1002 		return;
1003 	}
1004 
1005 	/*
1006 	 * Updates the log length of the last part of the panic log.
1007 	 */
1008 	panic_info->eph_other_log_len = PE_get_offset_into_panic_region(debug_buf_ptr) - panic_info->eph_other_log_offset;
1009 
1010 	/*
1011 	 * Updates the metadata at the beginning of the panic buffer,
1012 	 * updates the CRC.
1013 	 */
1014 	PE_update_panic_crc((unsigned char *)gPanicBase, &panicbuf_length);
1015 
1016 	/*
1017 	 * This is currently unused by platform KEXTs on embedded but is
1018 	 * kept for compatibility with the published IOKit interfaces.
1019 	 */
1020 	PESavePanicInfo((unsigned char *)gPanicBase, panicbuf_length);
1021 
1022 	PE_sync_panic_buffers();
1023 }
1024 
1025 #if CONFIG_SPTM
1026 /*
1027  * Patch thread state to appear as if a debugger stop IPI occurred, when a thread
1028  * is parked in SPTM panic loop. This allows stackshot to proceed as usual.
1029  */
1030 static void
DebuggerPatchupThreadState(int cpu,xnu_saved_registers_t * regp)1031 DebuggerPatchupThreadState(
1032 	int cpu, xnu_saved_registers_t *regp)
1033 {
1034 	cpu_data_t         *target_cpu_datap;
1035 	arm_saved_state_t  *statep;
1036 	vm_offset_t        kstackptr;
1037 
1038 	target_cpu_datap = (cpu_data_t *)CpuDataEntries[cpu].cpu_data_vaddr;
1039 	statep = target_cpu_datap->cpu_active_thread->machine.kpcb;
1040 	kstackptr = (vm_offset_t)target_cpu_datap->cpu_active_thread->machine.kstackptr;
1041 
1042 	target_cpu_datap->ipi_pc = regp->pc;
1043 	target_cpu_datap->ipi_lr = regp->lr;
1044 	target_cpu_datap->ipi_fp = regp->fp;
1045 
1046 	if (statep != NULL) {
1047 		statep->ss_64.fp = regp->fp;
1048 		statep->ss_64.lr = regp->lr;
1049 		statep->ss_64.sp = regp->sp;
1050 		statep->ss_64.pc = regp->pc;
1051 	} else if ((void *)kstackptr != NULL) {
1052 		arm_kernel_saved_state_t *kstatep = (arm_kernel_saved_state_t *)kstackptr;
1053 		kstatep->fp = regp->fp;
1054 		kstatep->lr = regp->lr;
1055 		kstatep->sp = regp->sp;
1056 	}
1057 }
1058 #endif
1059 
1060 /*
1061  * @function DebuggerXCallEnter
1062  *
1063  * @abstract IPI other cores so this core can run in a single-threaded context.
1064  *
1065  * @discussion This function should be called with the debugger lock held.  It
1066  * signals the other cores to go into a busy loop so this core can run in a
1067  * single-threaded context and inspect kernel memory.
1068  *
1069  * @param proceed_on_sync_failure If true, then go ahead and try to debug even
1070  * if we can't synch with the other cores.  This is inherently unsafe and should
1071  * only be used if the kernel is going down in flames anyway.
1072  *
1073  * @param is_stackshot If true, this is a stackshot request.
1074  *
1075  * @result returns KERN_OPERATION_TIMED_OUT if synchronization times out and
1076  * proceed_on_sync_failure is false.
1077  */
1078 kern_return_t
DebuggerXCallEnter(boolean_t proceed_on_sync_failure,bool is_stackshot)1079 DebuggerXCallEnter(
1080 	boolean_t proceed_on_sync_failure, bool is_stackshot)
1081 {
1082 	uint64_t max_mabs_time, current_mabs_time;
1083 	int cpu;
1084 	int timeout_cpu = -1;
1085 	int max_cpu;
1086 	unsigned int sync_pending;
1087 	cpu_data_t      *target_cpu_datap;
1088 	cpu_data_t      *cpu_data_ptr = getCpuDatap();
1089 
1090 	/* Check for nested debugger entry. */
1091 	cpu_data_ptr->debugger_active++;
1092 	if (cpu_data_ptr->debugger_active != 1) {
1093 		return KERN_SUCCESS;
1094 	}
1095 
1096 	/*
1097 	 * If debugger_sync is not 0, someone responded excessively late to the last
1098 	 * debug request (we zero the sync variable in the return function).  Zero it
1099 	 * again here.  This should prevent us from getting out of sync (heh) and
1100 	 * timing out on every entry to the debugger if we timeout once.
1101 	 */
1102 
1103 	os_atomic_store(&debugger_sync, 0, relaxed);
1104 	os_atomic_store(&mp_kdp_trap, 1, relaxed);
1105 	os_atomic_store(&debug_cpus_spinning, 0, relaxed);
1106 	trap_is_stackshot = is_stackshot;
1107 
1108 
1109 	/*
1110 	 * Try to signal all CPUs (except ourselves, of course).  Use debugger_sync to
1111 	 * synchronize with every CPU that we appeared to signal successfully (cpu_signal
1112 	 * is not synchronous).
1113 	 */
1114 	max_cpu = ml_get_max_cpu_number();
1115 
1116 	boolean_t immediate_halt = FALSE;
1117 	if (proceed_on_sync_failure && force_immediate_debug_halt) {
1118 		immediate_halt = TRUE;
1119 	}
1120 
1121 	if (!immediate_halt) {
1122 		for (cpu = 0; cpu <= max_cpu; cpu++) {
1123 			target_cpu_datap = (cpu_data_t *)CpuDataEntries[cpu].cpu_data_vaddr;
1124 
1125 			if ((target_cpu_datap == NULL) || (target_cpu_datap == cpu_data_ptr)) {
1126 				continue;
1127 			}
1128 
1129 			kern_return_t ret = cpu_signal(target_cpu_datap, SIGPdebug, (void *)NULL, NULL);
1130 			if (ret == KERN_SUCCESS) {
1131 				os_atomic_inc(&debugger_sync, relaxed);
1132 				os_atomic_inc(&debug_cpus_spinning, relaxed);
1133 			} else {
1134 				kprintf("%s: cpu_signal failed. cpu=%d ret=%d proceed=%d\n", __func__, cpu, ret, proceed_on_sync_failure);
1135 			}
1136 		}
1137 
1138 		max_mabs_time = os_atomic_load(&debug_ack_timeout, relaxed);
1139 
1140 		if (max_mabs_time > 0) {
1141 			current_mabs_time = mach_absolute_time();
1142 			max_mabs_time += current_mabs_time;
1143 			assert(max_mabs_time > current_mabs_time);
1144 		}
1145 
1146 		/*
1147 		 * Wait for DEBUG_ACK_TIMEOUT ns for a response from everyone we IPI'd.  If we
1148 		 * timeout, that is simply too bad; we don't have a true NMI, and one CPU may be
1149 		 * uninterruptibly spinning on someone else.  The best we can hope for is that
1150 		 * all other CPUs have either responded or are spinning in a context that is
1151 		 * debugger safe.
1152 		 */
1153 		do {
1154 			current_mabs_time = mach_absolute_time();
1155 			sync_pending = os_atomic_load(&debugger_sync, acquire);
1156 		} while ((sync_pending != 0) && (max_mabs_time == 0 || current_mabs_time < max_mabs_time));
1157 	}
1158 
1159 	if (!immediate_halt && max_mabs_time > 0 && current_mabs_time >= max_mabs_time) {
1160 		/*
1161 		 * We timed out trying to IPI the other CPUs. Skip counting any CPUs that
1162 		 * are offline; then we must account for the remainder, either counting
1163 		 * them as halted, or trying to dbgwrap them to get them to halt in the
1164 		 * case where the system is going down and we are running a dev fused
1165 		 * device.
1166 		 */
1167 		__builtin_arm_dmb(DMB_ISH);
1168 		for (cpu = 0; cpu <= max_cpu; cpu++) {
1169 			target_cpu_datap = (cpu_data_t *)CpuDataEntries[cpu].cpu_data_vaddr;
1170 
1171 			if ((target_cpu_datap == NULL) || (target_cpu_datap == cpu_data_ptr)) {
1172 				continue;
1173 			}
1174 			if (!(target_cpu_datap->cpu_signal & SIGPdebug)) {
1175 				continue;
1176 			}
1177 			if (processor_array[cpu]->state <= PROCESSOR_PENDING_OFFLINE) {
1178 				int dbg_sync_count;
1179 
1180 				/*
1181 				 * This is a processor that was successfully sent a SIGPdebug signal
1182 				 * but which hasn't acknowledged it because it went offline with
1183 				 * interrupts disabled before the IPI was delivered, so count it
1184 				 * as halted here.
1185 				 */
1186 				dbg_sync_count = os_atomic_dec(&debugger_sync, relaxed);
1187 				kprintf("%s>found CPU %d offline, debugger_sync=%d\n", __FUNCTION__, cpu, dbg_sync_count);
1188 				continue;
1189 			}
1190 			kprintf("%s>Debugger synch pending on cpu %d\n", __FUNCTION__, cpu);
1191 			timeout_cpu = cpu;
1192 #if CONFIG_SPTM
1193 			if (proceed_on_sync_failure) {
1194 				/*
1195 				 * If a core is spinning in the SPTM panic loop, consider it
1196 				 * as sync'd, and try to patch up the thread state from the
1197 				 * SPTM callee saved registers.
1198 				 */
1199 				bool sptm_panic_loop = false;
1200 				vm_offset_t base = other_percpu_base(cpu);
1201 				pmap_sptm_percpu_data_t *sptm_pcpu = PERCPU_GET_WITH_BASE(base, pmap_sptm_percpu);
1202 				uint64_t sptm_cpuid = sptm_pcpu->sptm_cpu_id;
1203 
1204 				if (sptm_get_cpu_state(sptm_cpuid, CPUSTATE_PANIC_SPIN, &sptm_panic_loop)
1205 				    == SPTM_SUCCESS && sptm_panic_loop) {
1206 					xnu_saved_registers_t regs;
1207 
1208 					if (sptm_copy_callee_saved_state(sptm_cpuid, &regs)
1209 					    == LIBSPTM_SUCCESS) {
1210 						DebuggerPatchupThreadState(cpu, &regs);
1211 					}
1212 
1213 					kprintf("%s>found CPU %d in SPTM\n", __FUNCTION__, cpu);
1214 					os_atomic_dec(&debugger_sync, relaxed);
1215 				}
1216 			}
1217 #endif
1218 		}
1219 
1220 		if (debugger_sync == 0) {
1221 			return KERN_SUCCESS;
1222 		} else if (!proceed_on_sync_failure) {
1223 			panic("%s>Debugger synch pending on cpu %d\n",
1224 			    __FUNCTION__, timeout_cpu);
1225 		}
1226 	}
1227 	if (immediate_halt || (max_mabs_time > 0 && current_mabs_time >= max_mabs_time)) {
1228 		if (immediate_halt) {
1229 			__builtin_arm_dmb(DMB_ISH);
1230 		}
1231 		for (cpu = 0; cpu <= max_cpu; cpu++) {
1232 			target_cpu_datap = (cpu_data_t *)CpuDataEntries[cpu].cpu_data_vaddr;
1233 
1234 			if ((target_cpu_datap == NULL) || (target_cpu_datap == cpu_data_ptr)) {
1235 				continue;
1236 			}
1237 			paniclog_append_noflush("Attempting to forcibly halt cpu %d\n", cpu);
1238 			dbgwrap_status_t halt_status = ml_dbgwrap_halt_cpu(cpu, 0);
1239 			if (halt_status < 0) {
1240 				paniclog_append_noflush("cpu %d failed to halt with error %d: %s\n", cpu, halt_status, ml_dbgwrap_strerror(halt_status));
1241 			} else {
1242 				if (halt_status > 0) {
1243 					paniclog_append_noflush("cpu %d halted with warning %d: %s\n", cpu, halt_status, ml_dbgwrap_strerror(halt_status));
1244 				}
1245 				target_cpu_datap->halt_status = CPU_HALTED;
1246 			}
1247 		}
1248 		for (cpu = 0; cpu <= max_cpu; cpu++) {
1249 			target_cpu_datap = (cpu_data_t *)CpuDataEntries[cpu].cpu_data_vaddr;
1250 
1251 			if ((target_cpu_datap == NULL) || (target_cpu_datap == cpu_data_ptr)) {
1252 				continue;
1253 			}
1254 			dbgwrap_status_t halt_status = ml_dbgwrap_halt_cpu_with_state(cpu,
1255 			    NSEC_PER_SEC, &target_cpu_datap->halt_state);
1256 			if ((halt_status < 0) || (halt_status == DBGWRAP_WARN_CPU_OFFLINE)) {
1257 				paniclog_append_noflush("Unable to obtain state for cpu %d with status %d: %s\n", cpu, halt_status, ml_dbgwrap_strerror(halt_status));
1258 				debug_ack_timeout_count++;
1259 			} else {
1260 				paniclog_append_noflush("cpu %d successfully halted\n", cpu);
1261 				target_cpu_datap->halt_status = CPU_HALTED_WITH_STATE;
1262 			}
1263 		}
1264 		if (immediate_halt) {
1265 			paniclog_append_noflush("Immediate halt requested on all cores\n");
1266 		} else {
1267 			paniclog_append_noflush("Debugger synchronization timed out; timeout %llu nanoseconds\n",
1268 			    os_atomic_load(&debug_ack_timeout, relaxed));
1269 		}
1270 	}
1271 	return KERN_SUCCESS;
1272 }
1273 
1274 /*
1275  * @function DebuggerXCallReturn
1276  *
1277  * @abstract Resume normal multicore operation after DebuggerXCallEnter()
1278  *
1279  * @discussion This function should be called with debugger lock held.
1280  */
1281 void
DebuggerXCallReturn(void)1282 DebuggerXCallReturn(
1283 	void)
1284 {
1285 	cpu_data_t      *cpu_data_ptr = getCpuDatap();
1286 	uint64_t max_mabs_time, current_mabs_time;
1287 
1288 	cpu_data_ptr->debugger_active--;
1289 	if (cpu_data_ptr->debugger_active != 0) {
1290 		return;
1291 	}
1292 
1293 	os_atomic_store(&mp_kdp_trap, 0, release);
1294 	os_atomic_store(&debugger_sync, 0, relaxed);
1295 
1296 	max_mabs_time = os_atomic_load(&debug_ack_timeout, relaxed);
1297 
1298 	if (max_mabs_time > 0) {
1299 		current_mabs_time = mach_absolute_time();
1300 		max_mabs_time += current_mabs_time;
1301 		assert(max_mabs_time > current_mabs_time);
1302 	}
1303 
1304 	/*
1305 	 * Wait for other CPUs to stop spinning on mp_kdp_trap (see DebuggerXCall).
1306 	 * It's possible for one or more CPUs to not decrement debug_cpus_spinning,
1307 	 * since they may be stuck somewhere else with interrupts disabled.
1308 	 * Wait for DEBUG_ACK_TIMEOUT ns for a response and move on if we don't get it.
1309 	 *
1310 	 * Note that the same is done in DebuggerXCallEnter, when we wait for other
1311 	 * CPUS to update debugger_sync. If we time out, let's hope for all CPUs to be
1312 	 * spinning in a debugger-safe context
1313 	 */
1314 	while ((os_atomic_load_exclusive(&debug_cpus_spinning, acquire) != 0) &&
1315 	    (max_mabs_time == 0 || current_mabs_time < max_mabs_time)) {
1316 		__builtin_arm_wfe();
1317 		current_mabs_time = mach_absolute_time();
1318 	}
1319 	os_atomic_clear_exclusive();
1320 
1321 	// checking debug_ack_timeout != 0 is a workaround for rdar://124242354
1322 	if (current_mabs_time >= max_mabs_time && os_atomic_load(&debug_ack_timeout, relaxed) != 0) {
1323 		panic("Resuming from debugger synchronization failed: waited %llu nanoseconds\n", os_atomic_load(&debug_ack_timeout, relaxed));
1324 	}
1325 }
1326 
1327 extern void wait_while_mp_kdp_trap(bool check_SIGPdebug);
1328 /*
1329  * Spin while mp_kdp_trap is set.
1330  *
1331  * processor_offline() calls this with check_SIGPdebug=true
1332  * to break out of the spin loop if the cpu has SIGPdebug
1333  * pending.
1334  */
1335 void
wait_while_mp_kdp_trap(bool check_SIGPdebug)1336 wait_while_mp_kdp_trap(bool check_SIGPdebug)
1337 {
1338 	bool found_mp_kdp_trap = false;
1339 	bool found_SIGPdebug = false;
1340 
1341 	while (os_atomic_load_exclusive(&mp_kdp_trap, acquire) != 0) {
1342 		found_mp_kdp_trap = true;
1343 		if (check_SIGPdebug && cpu_has_SIGPdebug_pending()) {
1344 			found_SIGPdebug = true;
1345 			break;
1346 		}
1347 		__builtin_arm_wfe();
1348 	}
1349 	os_atomic_clear_exclusive();
1350 
1351 	if (check_SIGPdebug && found_mp_kdp_trap) {
1352 		kprintf("%s>found_mp_kdp_trap=true found_SIGPdebug=%s\n", __FUNCTION__, found_SIGPdebug ? "true" : "false");
1353 	}
1354 }
1355 
1356 void
DebuggerXCall(void * ctx)1357 DebuggerXCall(
1358 	void            *ctx)
1359 {
1360 	boolean_t               save_context = FALSE;
1361 	vm_offset_t             kstackptr = 0;
1362 	arm_saved_state_t       *regs = (arm_saved_state_t *) ctx;
1363 
1364 	if (regs != NULL) {
1365 #if defined(__arm64__)
1366 		current_cpu_datap()->ipi_pc = (uint64_t)get_saved_state_pc(regs);
1367 		current_cpu_datap()->ipi_lr = (uint64_t)get_saved_state_lr(regs);
1368 		current_cpu_datap()->ipi_fp = (uint64_t)get_saved_state_fp(regs);
1369 		save_context = PSR64_IS_KERNEL(get_saved_state_cpsr(regs));
1370 #endif
1371 	}
1372 
1373 	kstackptr = (vm_offset_t)current_thread()->machine.kstackptr;
1374 
1375 #if defined(__arm64__)
1376 	arm_kernel_saved_state_t *state = (arm_kernel_saved_state_t *)kstackptr;
1377 
1378 	if (save_context) {
1379 		/* Save the interrupted context before acknowledging the signal */
1380 		current_thread()->machine.kpcb = regs;
1381 	} else if (regs) {
1382 		/* zero old state so machine_trace_thread knows not to backtrace it */
1383 		state->fp = 0;
1384 		state->pc_was_in_userspace = true;
1385 		state->lr = 0;
1386 		state->sp = 0;
1387 		state->ssbs = 0;
1388 		state->uao = 0;
1389 		state->dit = 0;
1390 #if HAS_MTE
1391 		state->tco = 0;
1392 #endif
1393 	}
1394 #endif
1395 
1396 	/*
1397 	 * When running in serial mode, the core capturing the dump may hold interrupts disabled
1398 	 * for a time longer than the timeout. That path includes logic to reset the timestamp
1399 	 * so that we do not eventually trigger the interrupt timeout assert().
1400 	 *
1401 	 * Here we check whether other cores have already gone over the timeout at this point
1402 	 * before spinning, so we at least cover the IPI reception path. After spinning, however,
1403 	 * we reset the timestamp so as to avoid hitting the interrupt timeout assert().
1404 	 */
1405 	if ((serialmode & SERIALMODE_OUTPUT) || trap_is_stackshot) {
1406 		ml_interrupt_masked_debug_end();
1407 	}
1408 
1409 	/*
1410 	 * Before we decrement debugger sync, do stackshot preflight work (if applicable).
1411 	 * Namely, we want to signal that we're available to do stackshot work, and we need to
1412 	 * signal so before the stackshot-calling CPU starts work.
1413 	 */
1414 
1415 	if (trap_is_stackshot) {
1416 		stackshot_cpu_preflight();
1417 	}
1418 
1419 	os_atomic_dec(&debugger_sync, release);
1420 
1421 	/* If we trapped because we're doing a stackshot, do our work first. */
1422 	if (trap_is_stackshot) {
1423 		stackshot_aux_cpu_entry();
1424 	}
1425 
1426 
1427 	wait_while_mp_kdp_trap(false);
1428 
1429 	/**
1430 	 * Alert the triggering CPU that this CPU is done spinning. The CPU that
1431 	 * signalled all of the other CPUs will wait (in DebuggerXCallReturn) for
1432 	 * all of the CPUs to exit the above loop before continuing.
1433 	 */
1434 	os_atomic_dec(&debug_cpus_spinning, release);
1435 
1436 #if SCHED_HYGIENE_DEBUG
1437 	/*
1438 	 * We also abandon the measurement for preemption disable
1439 	 * timeouts, if any. Normally, time in interrupt handlers would be
1440 	 * subtracted from preemption disable time, and this will happen
1441 	 * up to this point here, but since we here "end" the interrupt
1442 	 * handler prematurely (from the point of view of interrupt masked
1443 	 * debugging), the time spinning would otherwise still be
1444 	 * attributed to preemption disable time, and potentially trigger
1445 	 * an event, which could be a panic.
1446 	 */
1447 	abandon_preemption_disable_measurement();
1448 
1449 	if ((serialmode & SERIALMODE_OUTPUT) || trap_is_stackshot) {
1450 		ml_interrupt_masked_debug_start((void *)current_thread()->machine.int_handler_addr, current_thread()->machine.int_type);
1451 	}
1452 #endif /* SCHED_HYGIENE_DEBUG */
1453 
1454 #if defined(__arm64__)
1455 	current_thread()->machine.kpcb = NULL;
1456 #endif /* defined(__arm64__) */
1457 
1458 	/* Any cleanup for our pushed context should go here */
1459 }
1460 
1461 void
DebuggerCall(unsigned int reason,void * ctx)1462 DebuggerCall(
1463 	unsigned int    reason,
1464 	void            *ctx)
1465 {
1466 #if     !MACH_KDP
1467 #pragma unused(reason,ctx)
1468 #endif /* !MACH_KDP */
1469 
1470 #if ALTERNATE_DEBUGGER
1471 	alternate_debugger_enter();
1472 #endif
1473 
1474 #if     MACH_KDP
1475 	kdp_trap(reason, (struct arm_saved_state *)ctx);
1476 #else
1477 	/* TODO: decide what to do if no debugger config */
1478 #endif
1479 }
1480 
1481 boolean_t
bootloader_valid_page(ppnum_t ppn)1482 bootloader_valid_page(ppnum_t ppn)
1483 {
1484 	return pmap_bootloader_page(ppn);
1485 }
1486