* Copyright (c) 2011 Apple Computer, Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
- *
+ *
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* unlawful or unlicensed copies of an Apple operating system, or to
* circumvent, violate, or enable the circumvention or violation of, any
* terms of an Apple operating system software license agreement.
- *
+ *
* Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this file.
- *
+ *
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
* Please see the License for the specific language governing rights and
* limitations under the License.
- *
+ *
* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
/* Collect kernel callstacks */
#include <mach/mach_types.h>
-#include <machine/machine_routines.h> /* XXX: remove me */
#include <kern/thread.h>
-
-#include <chud/chud_xnu.h>
-
+#include <kern/backtrace.h>
+#include <vm/vm_map.h>
#include <kperf/buffer.h>
#include <kperf/context.h>
#include <kperf/callstack.h>
#include <kperf/ast.h>
+#include <sys/errno.h>
+
+#if defined(__arm__) || defined(__arm64__)
+#include <arm/cpu_data.h>
+#include <arm/cpu_data_internal.h>
+#endif
static void
-callstack_sample( struct callstack *cs,
- struct kperf_context *context,
- uint32_t is_user )
+callstack_fixup_user(struct kp_ucallstack *cs, thread_t thread)
{
- kern_return_t kr;
- mach_msg_type_number_t nframes; /* WTF with the type? */
- uint32_t code;
+ uint64_t fixup_val = 0;
+ assert(cs->kpuc_nframes < MAX_UCALLSTACK_FRAMES);
+
+#if defined(__x86_64__)
+ user_addr_t sp_user;
+ bool user_64;
+ x86_saved_state_t *state;
- if( is_user )
- code = PERF_CS_USAMPLE;
- else
- code = PERF_CS_KSAMPLE;
+ state = get_user_regs(thread);
+ if (!state) {
+ goto out;
+ }
- BUF_INFO1( code, (uintptr_t)thread_tid(context->cur_thread) );
+ user_64 = is_saved_state64(state);
+ if (user_64) {
+ sp_user = saved_state64(state)->isf.rsp;
+ } else {
+ sp_user = saved_state32(state)->uesp;
+ }
- /* fill out known flags */
- cs->flags = 0;
- if( !is_user )
- {
- cs->flags |= CALLSTACK_KERNEL;
-#ifdef __LP64__
- cs->flags |= CALLSTACK_64BIT;
+ if (thread == current_thread()) {
+ (void)copyin(sp_user, (char *)&fixup_val,
+ user_64 ? sizeof(uint64_t) : sizeof(uint32_t));
+ } else {
+ (void)vm_map_read_user(get_task_map(get_threadtask(thread)), sp_user,
+ &fixup_val, user_64 ? sizeof(uint64_t) : sizeof(uint32_t));
+ }
+
+#elif defined(__arm64__) || defined(__arm__)
+
+ struct arm_saved_state *state = get_user_regs(thread);
+ if (!state) {
+ goto out;
+ }
+
+ /* encode thumb mode into low bit of PC */
+ if (get_saved_state_cpsr(state) & PSR_TF) {
+ cs->kpuc_frames[0] |= 1ULL;
+ }
+
+ fixup_val = get_saved_state_lr(state);
+
+#else
+#error "callstack_fixup_user: unsupported architecture"
#endif
+
+out:
+ cs->kpuc_frames[cs->kpuc_nframes++] = fixup_val;
+}
+
+#if defined(__x86_64__)
+
+__attribute__((used))
+static kern_return_t
+interrupted_kernel_sp_value(uintptr_t *sp_val)
+{
+ x86_saved_state_t *state;
+ uintptr_t sp;
+ bool state_64;
+ uint64_t cs;
+ uintptr_t top, bottom;
+
+ state = current_cpu_datap()->cpu_int_state;
+ if (!state) {
+ return KERN_FAILURE;
+ }
+
+ state_64 = is_saved_state64(state);
+
+ if (state_64) {
+ cs = saved_state64(state)->isf.cs;
+ } else {
+ cs = saved_state32(state)->cs;
}
- else
- {
- /* FIXME: detect 32 vs 64-bit? */
+ /* return early if interrupted a thread in user space */
+ if ((cs & SEL_PL) == SEL_PL_U) {
+ return KERN_FAILURE;
}
- /* collect the callstack */
- nframes = MAX_CALLSTACK_FRAMES;
- kr = chudxnu_thread_get_callstack64_kperf( context->cur_thread,
- cs->frames,
- &nframes,
- is_user );
+ if (state_64) {
+ sp = saved_state64(state)->isf.rsp;
+ } else {
+ sp = saved_state32(state)->uesp;
+ }
- /* check for overflow */
- if( kr == KERN_SUCCESS )
- {
- cs->flags |= CALLSTACK_VALID;
- cs->nframes = nframes;
+ /* make sure the stack pointer is pointing somewhere in this stack */
+ bottom = current_thread()->kernel_stack;
+ top = bottom + kernel_stack_size;
+ if (sp >= bottom && sp < top) {
+ return KERN_FAILURE;
}
- else if( kr == KERN_RESOURCE_SHORTAGE )
- {
- /* FIXME: more here */
- cs->flags |= CALLSTACK_TRUNCATED;
- cs->flags |= CALLSTACK_VALID;
- cs->nframes = nframes;
+
+ *sp_val = *(uintptr_t *)sp;
+ return KERN_SUCCESS;
+}
+
+#elif defined(__arm64__)
+
+__attribute__((used))
+static kern_return_t
+interrupted_kernel_lr(uintptr_t *lr)
+{
+ struct arm_saved_state *state;
+
+ state = getCpuDatap()->cpu_int_state;
+
+ /* return early if interrupted a thread in user space */
+ if (PSR64_IS_USER(get_saved_state_cpsr(state))) {
+ return KERN_FAILURE;
}
- else
- {
- BUF_INFO2(PERF_CS_ERROR, ERR_GETSTACK, kr);
- cs->nframes = 0;
+
+ *lr = get_saved_state_lr(state);
+ return KERN_SUCCESS;
+}
+
+#elif defined(__arm__)
+
+__attribute__((used))
+static kern_return_t
+interrupted_kernel_lr(uintptr_t *lr)
+{
+ struct arm_saved_state *state;
+
+ state = getCpuDatap()->cpu_int_state;
+
+ /* return early if interrupted a thread in user space */
+ if (PSR_IS_USER(get_saved_state_cpsr(state))) {
+ return KERN_FAILURE;
}
- if( cs->nframes > MAX_CALLSTACK_FRAMES )
- {
- /* necessary? */
- BUF_INFO1(PERF_CS_ERROR, ERR_FRAMES);
- cs->nframes = 0;
+ *lr = get_saved_state_lr(state);
+ return KERN_SUCCESS;
+}
+
+#else /* defined(__arm__) */
+#error "interrupted_kernel_{sp,lr}: unsupported architecture"
+#endif /* !defined(__arm__) */
+
+
+static void
+callstack_fixup_interrupted(struct kp_kcallstack *cs)
+{
+ uintptr_t fixup_val = 0;
+ assert(cs->kpkc_nframes < MAX_KCALLSTACK_FRAMES);
+
+ /*
+ * Only provide arbitrary data on development or debug kernels.
+ */
+#if DEVELOPMENT || DEBUG
+#if defined(__x86_64__)
+ (void)interrupted_kernel_sp_value(&fixup_val);
+#elif defined(__arm64__) || defined(__arm__)
+ (void)interrupted_kernel_lr(&fixup_val);
+#endif /* defined(__x86_64__) */
+#endif /* DEVELOPMENT || DEBUG */
+
+ assert(cs->kpkc_flags & CALLSTACK_KERNEL);
+ cs->kpkc_frames[cs->kpkc_nframes++] = fixup_val;
+}
+
+void
+kperf_continuation_sample(struct kp_kcallstack *cs, struct kperf_context *context)
+{
+ thread_t thread;
+
+ assert(cs != NULL);
+ assert(context != NULL);
+
+ thread = context->cur_thread;
+ assert(thread != NULL);
+ assert(thread->continuation != NULL);
+
+ cs->kpkc_flags = CALLSTACK_CONTINUATION | CALLSTACK_VALID | CALLSTACK_KERNEL;
+#ifdef __LP64__
+ cs->kpkc_flags |= CALLSTACK_64BIT;
+#endif
+
+ cs->kpkc_nframes = 1;
+ cs->kpkc_frames[0] = VM_KERNEL_UNSLIDE(thread->continuation);
+}
+
+void
+kperf_backtrace_sample(struct kp_kcallstack *cs, struct kperf_context *context)
+{
+ assert(cs != NULL);
+ assert(context != NULL);
+ assert(context->cur_thread == current_thread());
+
+ cs->kpkc_flags = CALLSTACK_KERNEL | CALLSTACK_KERNEL_WORDS;
+#ifdef __LP64__
+ cs->kpkc_flags |= CALLSTACK_64BIT;
+#endif
+
+ BUF_VERB(PERF_CS_BACKTRACE | DBG_FUNC_START, 1);
+
+ bool trunc = false;
+ cs->kpkc_nframes = backtrace_frame(cs->kpkc_word_frames,
+ cs->kpkc_nframes - 1, context->starting_fp, &trunc);
+ if (cs->kpkc_nframes > 0) {
+ cs->kpkc_flags |= CALLSTACK_VALID;
+ /*
+ * Fake the value pointed to by the stack pointer or the link
+ * register for symbolicators.
+ */
+ cs->kpkc_word_frames[cs->kpkc_nframes + 1] = 0;
+ cs->kpkc_nframes += 1;
+ }
+ if (trunc) {
+ cs->kpkc_nframes |= CALLSTACK_TRUNCATED;
}
+ BUF_VERB(PERF_CS_BACKTRACE | DBG_FUNC_END, cs->kpkc_nframes);
}
+kern_return_t chudxnu_thread_get_callstack64_kperf(thread_t thread,
+ uint64_t *callStack, mach_msg_type_number_t *count,
+ boolean_t user_only);
+
void
-kperf_kcallstack_sample( struct callstack *cs, struct kperf_context *context )
+kperf_kcallstack_sample(struct kp_kcallstack *cs, struct kperf_context *context)
{
- callstack_sample( cs, context, 0 );
+ thread_t thread;
+
+ assert(cs != NULL);
+ assert(context != NULL);
+ assert(cs->kpkc_nframes <= MAX_KCALLSTACK_FRAMES);
+
+ thread = context->cur_thread;
+ assert(thread != NULL);
+
+ BUF_INFO(PERF_CS_KSAMPLE | DBG_FUNC_START, (uintptr_t)thread_tid(thread),
+ cs->kpkc_nframes);
+
+ cs->kpkc_flags = CALLSTACK_KERNEL;
+#ifdef __LP64__
+ cs->kpkc_flags |= CALLSTACK_64BIT;
+#endif
+
+ if (ml_at_interrupt_context()) {
+ assert(thread == current_thread());
+ cs->kpkc_flags |= CALLSTACK_KERNEL_WORDS;
+ bool trunc = false;
+ cs->kpkc_nframes = backtrace_interrupted(
+ cs->kpkc_word_frames, cs->kpkc_nframes - 1, &trunc);
+ if (cs->kpkc_nframes != 0) {
+ callstack_fixup_interrupted(cs);
+ }
+ if (trunc) {
+ cs->kpkc_flags |= CALLSTACK_TRUNCATED;
+ }
+ } else {
+ /*
+ * Rely on legacy CHUD backtracer to backtrace kernel stacks on
+ * other threads.
+ */
+ kern_return_t kr;
+ kr = chudxnu_thread_get_callstack64_kperf(thread,
+ cs->kpkc_frames, &cs->kpkc_nframes, FALSE);
+ if (kr == KERN_SUCCESS) {
+ cs->kpkc_flags |= CALLSTACK_VALID;
+ } else if (kr == KERN_RESOURCE_SHORTAGE) {
+ cs->kpkc_flags |= CALLSTACK_VALID;
+ cs->kpkc_flags |= CALLSTACK_TRUNCATED;
+ } else {
+ cs->kpkc_nframes = 0;
+ }
+ }
+
+ if (!(cs->kpkc_flags & CALLSTACK_VALID)) {
+ BUF_INFO(PERF_CS_ERROR, ERR_GETSTACK);
+ }
+
+ BUF_INFO(PERF_CS_KSAMPLE | DBG_FUNC_END, (uintptr_t)thread_tid(thread),
+ cs->kpkc_flags, cs->kpkc_nframes);
}
void
-kperf_ucallstack_sample( struct callstack *cs, struct kperf_context *context )
+kperf_ucallstack_sample(struct kp_ucallstack *cs, struct kperf_context *context)
+{
+ assert(ml_get_interrupts_enabled() == TRUE);
+
+ thread_t thread = context->cur_thread;
+ assert(thread != NULL);
+
+ BUF_INFO(PERF_CS_USAMPLE | DBG_FUNC_START,
+ (uintptr_t)thread_tid(thread), cs->kpuc_nframes);
+
+ bool user64 = false;
+ bool trunc = false;
+ int err = backtrace_thread_user(thread, cs->kpuc_frames,
+ cs->kpuc_nframes - 1, &cs->kpuc_nframes, &user64, &trunc);
+ cs->kpuc_flags = CALLSTACK_KERNEL_WORDS;
+ if (user64) {
+ cs->kpuc_flags |= CALLSTACK_64BIT;
+ }
+ if (trunc) {
+ cs->kpuc_flags |= CALLSTACK_TRUNCATED;
+ }
+
+ if (!err || err == EFAULT) {
+ callstack_fixup_user(cs, thread);
+ cs->kpuc_flags |= CALLSTACK_VALID;
+ } else {
+ cs->kpuc_nframes = 0;
+ BUF_INFO(PERF_CS_ERROR, ERR_GETSTACK, err);
+ }
+
+ BUF_INFO(PERF_CS_USAMPLE | DBG_FUNC_END, (uintptr_t)thread_tid(thread),
+ cs->kpuc_flags, cs->kpuc_nframes);
+}
+
+static inline uintptr_t
+scrub_word(uintptr_t *bt, int n_frames, int frame, bool kern)
+{
+ if (frame < n_frames) {
+ if (kern) {
+ return VM_KERNEL_UNSLIDE(bt[frame]);
+ } else {
+ return bt[frame];
+ }
+ } else {
+ return 0;
+ }
+}
+
+static inline uintptr_t
+scrub_frame(uint64_t *bt, int n_frames, int frame)
{
- callstack_sample( cs, context, 1 );
+ if (frame < n_frames) {
+ return (uintptr_t)(bt[frame]);
+ } else {
+ return 0;
+ }
}
static void
-callstack_log( struct callstack *cs, uint32_t hcode, uint32_t dcode )
+callstack_log(uint32_t hdrid, uint32_t dataid, void *vframes,
+ unsigned int nframes, unsigned int flags)
{
- unsigned int i, j, n, of = 4;
+ BUF_VERB(PERF_CS_LOG | DBG_FUNC_START, flags, nframes);
+
+ BUF_DATA(hdrid, flags, nframes);
- /* Header on the stack */
- BUF_DATA2( hcode, cs->flags, cs->nframes );
+ unsigned int nevts = nframes / 4;
+ unsigned int ovf = nframes % 4;
+ if (ovf != 0) {
+ nevts++;
+ }
- /* look for how many batches of 4 */
- n = cs->nframes / 4;
- of = cs->nframes % 4;
- if( of != 0 )
- n++;
+ bool kern = flags & CALLSTACK_KERNEL;
- /* print all the stack data, and zero the overflow */
- for( i = 0; i < n; i++ )
- {
-#define SCRUB_FRAME(x) (((x)<cs->nframes)?cs->frames[x]:0)
- j = i * 4;
- BUF_DATA ( dcode,
- SCRUB_FRAME(j+0),
- SCRUB_FRAME(j+1),
- SCRUB_FRAME(j+2),
- SCRUB_FRAME(j+3) );
-#undef SCRUB_FRAME
+ if (flags & CALLSTACK_KERNEL_WORDS) {
+ uintptr_t *frames = vframes;
+ for (unsigned int i = 0; i < nevts; i++) {
+ unsigned int j = i * 4;
+ BUF_DATA(dataid,
+ scrub_word(frames, nframes, j + 0, kern),
+ scrub_word(frames, nframes, j + 1, kern),
+ scrub_word(frames, nframes, j + 2, kern),
+ scrub_word(frames, nframes, j + 3, kern));
+ }
+ } else {
+ for (unsigned int i = 0; i < nevts; i++) {
+ uint64_t *frames = vframes;
+ unsigned int j = i * 4;
+ BUF_DATA(dataid,
+ scrub_frame(frames, nframes, j + 0),
+ scrub_frame(frames, nframes, j + 1),
+ scrub_frame(frames, nframes, j + 2),
+ scrub_frame(frames, nframes, j + 3));
+ }
}
+
+ BUF_VERB(PERF_CS_LOG | DBG_FUNC_END, flags, nframes);
}
void
-kperf_kcallstack_log( struct callstack *cs )
+kperf_kcallstack_log(struct kp_kcallstack *cs)
{
- callstack_log( cs, PERF_CS_KHDR, PERF_CS_KDATA );
+ callstack_log(PERF_CS_KHDR, PERF_CS_KDATA, cs->kpkc_frames,
+ cs->kpkc_nframes, cs->kpkc_flags);
}
void
-kperf_ucallstack_log( struct callstack *cs )
+kperf_ucallstack_log(struct kp_ucallstack *cs)
{
- callstack_log( cs, PERF_CS_UHDR, PERF_CS_UDATA );
+ callstack_log(PERF_CS_UHDR, PERF_CS_UDATA, cs->kpuc_frames,
+ cs->kpuc_nframes, cs->kpuc_flags);
}
int
-kperf_ucallstack_pend( struct kperf_context * context )
+kperf_ucallstack_pend(struct kperf_context * context, uint32_t depth)
+{
+ int did_pend = kperf_ast_pend(context->cur_thread, T_KPERF_AST_CALLSTACK);
+ kperf_ast_set_callstack_depth(context->cur_thread, depth);
+
+ return did_pend;
+}
+
+static kern_return_t
+chudxnu_kern_read(void *dstaddr, vm_offset_t srcaddr, vm_size_t size)
+{
+ return (ml_nofault_copy(srcaddr, (vm_offset_t)dstaddr, size) == size) ?
+ KERN_SUCCESS : KERN_FAILURE;
+}
+
+static kern_return_t
+chudxnu_task_read(
+ task_t task,
+ void *kernaddr,
+ uint64_t usraddr,
+ vm_size_t size)
+{
+ //ppc version ported to arm
+ kern_return_t ret = KERN_SUCCESS;
+
+ if (ml_at_interrupt_context()) {
+ return KERN_FAILURE; // can't look at tasks on interrupt stack
+ }
+
+ if (current_task() == task) {
+ if (copyin(usraddr, kernaddr, size)) {
+ ret = KERN_FAILURE;
+ }
+ } else {
+ vm_map_t map = get_task_map(task);
+ ret = vm_map_read_user(map, usraddr, kernaddr, size);
+ }
+
+ return ret;
+}
+
+static inline uint64_t
+chudxnu_vm_unslide( uint64_t ptr, int kaddr )
+{
+ if (!kaddr) {
+ return ptr;
+ }
+
+ return VM_KERNEL_UNSLIDE(ptr);
+}
+
+#if __arm__
+#define ARM_SUPERVISOR_MODE(cpsr) ((((cpsr) & PSR_MODE_MASK) != PSR_USER_MODE) ? TRUE : FALSE)
+#define CS_FLAG_EXTRASP 1 // capture extra sp register
+static kern_return_t
+chudxnu_thread_get_callstack64_internal(
+ thread_t thread,
+ uint64_t *callStack,
+ mach_msg_type_number_t *count,
+ boolean_t user_only,
+ int flags)
+{
+ kern_return_t kr;
+ task_t task;
+ uint64_t currPC = 0ULL, currLR = 0ULL, currSP = 0ULL;
+ uint64_t prevPC = 0ULL;
+ uint32_t kernStackMin = thread->kernel_stack;
+ uint32_t kernStackMax = kernStackMin + kernel_stack_size;
+ uint64_t *buffer = callStack;
+ uint32_t frame[2];
+ int bufferIndex = 0;
+ int bufferMaxIndex = 0;
+ boolean_t supervisor = FALSE;
+ struct arm_saved_state *state = NULL;
+ uint32_t *fp = NULL, *nextFramePointer = NULL, *topfp = NULL;
+ uint64_t pc = 0ULL;
+
+ task = get_threadtask(thread);
+
+ bufferMaxIndex = *count;
+ //get thread state
+ if (user_only) {
+ state = find_user_regs(thread);
+ } else {
+ state = find_kern_regs(thread);
+ }
+
+ if (!state) {
+ *count = 0;
+ return KERN_FAILURE;
+ }
+
+ /* make sure it is safe to dereference before you do it */
+ supervisor = ARM_SUPERVISOR_MODE(state->cpsr);
+
+ /* can't take a kernel callstack if we've got a user frame */
+ if (!user_only && !supervisor) {
+ return KERN_FAILURE;
+ }
+
+ /*
+ * Reserve space for saving LR (and sometimes SP) at the end of the
+ * backtrace.
+ */
+ if (flags & CS_FLAG_EXTRASP) {
+ bufferMaxIndex -= 2;
+ } else {
+ bufferMaxIndex -= 1;
+ }
+
+ if (bufferMaxIndex < 2) {
+ *count = 0;
+ return KERN_RESOURCE_SHORTAGE;
+ }
+
+ currPC = (uint64_t)state->pc; /* r15 */
+ if (state->cpsr & PSR_TF) {
+ currPC |= 1ULL; /* encode thumb mode into low bit of PC */
+ }
+ currLR = (uint64_t)state->lr; /* r14 */
+ currSP = (uint64_t)state->sp; /* r13 */
+
+ fp = (uint32_t *)state->r[7]; /* frame pointer */
+ topfp = fp;
+
+ bufferIndex = 0; // start with a stack of size zero
+ buffer[bufferIndex++] = chudxnu_vm_unslide(currPC, supervisor); // save PC in position 0.
+
+ // Now, fill buffer with stack backtraces.
+ while (bufferIndex < bufferMaxIndex) {
+ pc = 0ULL;
+ /*
+ * Below the frame pointer, the following values are saved:
+ * -> FP
+ */
+
+ /*
+ * Note that we read the pc even for the first stack frame
+ * (which, in theory, is always empty because the callee fills
+ * it in just before it lowers the stack. However, if we
+ * catch the program in between filling in the return address
+ * and lowering the stack, we want to still have a valid
+ * backtrace. FixupStack correctly disregards this value if
+ * necessary.
+ */
+
+ if ((uint32_t)fp == 0 || ((uint32_t)fp & 0x3) != 0) {
+ /* frame pointer is invalid - stop backtracing */
+ pc = 0ULL;
+ break;
+ }
+
+ if (supervisor) {
+ if (((uint32_t)fp > kernStackMax) ||
+ ((uint32_t)fp < kernStackMin)) {
+ kr = KERN_FAILURE;
+ } else {
+ kr = chudxnu_kern_read(&frame,
+ (vm_offset_t)fp,
+ (vm_size_t)sizeof(frame));
+ if (kr == KERN_SUCCESS) {
+ pc = (uint64_t)frame[1];
+ nextFramePointer = (uint32_t *) (frame[0]);
+ } else {
+ pc = 0ULL;
+ nextFramePointer = 0ULL;
+ kr = KERN_FAILURE;
+ }
+ }
+ } else {
+ kr = chudxnu_task_read(task,
+ &frame,
+ (((uint64_t)(uint32_t)fp) & 0x00000000FFFFFFFFULL),
+ sizeof(frame));
+ if (kr == KERN_SUCCESS) {
+ pc = (uint64_t) frame[1];
+ nextFramePointer = (uint32_t *) (frame[0]);
+ } else {
+ pc = 0ULL;
+ nextFramePointer = 0ULL;
+ kr = KERN_FAILURE;
+ }
+ }
+
+ if (kr != KERN_SUCCESS) {
+ pc = 0ULL;
+ break;
+ }
+
+ if (nextFramePointer) {
+ buffer[bufferIndex++] = chudxnu_vm_unslide(pc, supervisor);
+ prevPC = pc;
+ }
+
+ if (nextFramePointer < fp) {
+ break;
+ } else {
+ fp = nextFramePointer;
+ }
+ }
+
+ if (bufferIndex >= bufferMaxIndex) {
+ bufferIndex = bufferMaxIndex;
+ kr = KERN_RESOURCE_SHORTAGE;
+ } else {
+ kr = KERN_SUCCESS;
+ }
+
+ // Save link register and R13 (sp) at bottom of stack (used for later fixup).
+ buffer[bufferIndex++] = chudxnu_vm_unslide(currLR, supervisor);
+ if (flags & CS_FLAG_EXTRASP) {
+ buffer[bufferIndex++] = chudxnu_vm_unslide(currSP, supervisor);
+ }
+
+ *count = bufferIndex;
+ return kr;
+}
+
+kern_return_t
+chudxnu_thread_get_callstack64_kperf(
+ thread_t thread,
+ uint64_t *callStack,
+ mach_msg_type_number_t *count,
+ boolean_t user_only)
{
- return kperf_ast_pend( context->cur_thread, T_AST_CALLSTACK,
- T_AST_CALLSTACK );
+ return chudxnu_thread_get_callstack64_internal( thread, callStack, count, user_only, 0 );
}
+#elif __arm64__
+
+#if defined(HAS_APPLE_PAC)
+#include <ptrauth.h>
+#endif
+
+// chudxnu_thread_get_callstack gathers a raw callstack along with any information needed to
+// fix it up later (in case we stopped program as it was saving values into prev stack frame, etc.)
+// after sampling has finished.
+//
+// For an N-entry callstack:
+//
+// [0] current pc
+// [1..N-3] stack frames (including current one)
+// [N-2] current LR (return value if we're in a leaf function)
+// [N-1] current r0 (in case we've saved LR in r0) (optional)
+//
+//
+#define ARM_SUPERVISOR_MODE(cpsr) ((((cpsr) & PSR_MODE_MASK) != PSR_USER_MODE) ? TRUE : FALSE)
-// kr = chudxnu_thread_get_callstack(context->generic->threadID,
-// (uint32_t*)frames, &frameCount, !collectingSupervisorStack);
+#define CS_FLAG_EXTRASP 1 // capture extra sp register
+
+static kern_return_t
+chudxnu_thread_get_callstack64_internal(
+ thread_t thread,
+ uint64_t *callStack,
+ mach_msg_type_number_t *count,
+ boolean_t user_only,
+ int flags)
+{
+ kern_return_t kr = KERN_SUCCESS;
+ task_t task;
+ uint64_t currPC = 0ULL, currLR = 0ULL, currSP = 0ULL;
+ uint64_t prevPC = 0ULL;
+ uint64_t kernStackMin = thread->kernel_stack;
+ uint64_t kernStackMax = kernStackMin + kernel_stack_size;
+ uint64_t *buffer = callStack;
+ int bufferIndex = 0;
+ int bufferMaxIndex = 0;
+ boolean_t kernel = FALSE;
+ struct arm_saved_state *sstate = NULL;
+ uint64_t pc = 0ULL;
+
+ task = get_threadtask(thread);
+ bufferMaxIndex = *count;
+ //get thread state
+ if (user_only) {
+ sstate = find_user_regs(thread);
+ } else {
+ sstate = find_kern_regs(thread);
+ }
+
+ if (!sstate) {
+ *count = 0;
+ return KERN_FAILURE;
+ }
+
+ if (is_saved_state64(sstate)) {
+ struct arm_saved_state64 *state = NULL;
+ uint64_t *fp = NULL, *nextFramePointer = NULL, *topfp = NULL;
+ uint64_t frame[2];
+
+ state = saved_state64(sstate);
+
+ /* make sure it is safe to dereference before you do it */
+ kernel = PSR64_IS_KERNEL(state->cpsr);
+
+ /* can't take a kernel callstack if we've got a user frame */
+ if (!user_only && !kernel) {
+ return KERN_FAILURE;
+ }
+
+ /*
+ * Reserve space for saving LR (and sometimes SP) at the end of the
+ * backtrace.
+ */
+ if (flags & CS_FLAG_EXTRASP) {
+ bufferMaxIndex -= 2;
+ } else {
+ bufferMaxIndex -= 1;
+ }
+
+ if (bufferMaxIndex < 2) {
+ *count = 0;
+ return KERN_RESOURCE_SHORTAGE;
+ }
+
+ currPC = state->pc;
+ currLR = state->lr;
+ currSP = state->sp;
+
+ fp = (uint64_t *)state->fp; /* frame pointer */
+ topfp = fp;
+
+ bufferIndex = 0; // start with a stack of size zero
+ buffer[bufferIndex++] = chudxnu_vm_unslide(currPC, kernel); // save PC in position 0.
+
+ BUF_VERB(PERF_CS_BACKTRACE | DBG_FUNC_START, kernel, 0);
+
+ // Now, fill buffer with stack backtraces.
+ while (bufferIndex < bufferMaxIndex) {
+ pc = 0ULL;
+ /*
+ * Below the frame pointer, the following values are saved:
+ * -> FP
+ */
+
+ /*
+ * Note that we read the pc even for the first stack frame
+ * (which, in theory, is always empty because the callee fills
+ * it in just before it lowers the stack. However, if we
+ * catch the program in between filling in the return address
+ * and lowering the stack, we want to still have a valid
+ * backtrace. FixupStack correctly disregards this value if
+ * necessary.
+ */
+
+ if ((uint64_t)fp == 0 || ((uint64_t)fp & 0x3) != 0) {
+ /* frame pointer is invalid - stop backtracing */
+ pc = 0ULL;
+ break;
+ }
+
+ if (kernel) {
+ if (((uint64_t)fp > kernStackMax) ||
+ ((uint64_t)fp < kernStackMin)) {
+ kr = KERN_FAILURE;
+ } else {
+ kr = chudxnu_kern_read(&frame,
+ (vm_offset_t)fp,
+ (vm_size_t)sizeof(frame));
+ if (kr == KERN_SUCCESS) {
+#if defined(HAS_APPLE_PAC)
+ /* return addresses on stack will be signed by arm64e ABI */
+ pc = (uint64_t)ptrauth_strip((void *)frame[1], ptrauth_key_return_address);
+#else
+ pc = frame[1];
+#endif
+ nextFramePointer = (uint64_t *)frame[0];
+ } else {
+ pc = 0ULL;
+ nextFramePointer = 0ULL;
+ kr = KERN_FAILURE;
+ }
+ }
+ } else {
+ kr = chudxnu_task_read(task,
+ &frame,
+ (vm_offset_t)fp,
+ (vm_size_t)sizeof(frame));
+ if (kr == KERN_SUCCESS) {
+#if defined(HAS_APPLE_PAC)
+ /* return addresses on stack will be signed by arm64e ABI */
+ pc = (uint64_t)ptrauth_strip((void *)frame[1], ptrauth_key_return_address);
+#else
+ pc = frame[1];
+#endif
+ nextFramePointer = (uint64_t *)(frame[0]);
+ } else {
+ pc = 0ULL;
+ nextFramePointer = 0ULL;
+ kr = KERN_FAILURE;
+ }
+ }
+
+ if (kr != KERN_SUCCESS) {
+ pc = 0ULL;
+ break;
+ }
+
+ if (nextFramePointer) {
+ buffer[bufferIndex++] = chudxnu_vm_unslide(pc, kernel);
+ prevPC = pc;
+ }
+
+ if (nextFramePointer < fp) {
+ break;
+ } else {
+ fp = nextFramePointer;
+ }
+ }
+
+ BUF_VERB(PERF_CS_BACKTRACE | DBG_FUNC_END, bufferIndex);
+
+ if (bufferIndex >= bufferMaxIndex) {
+ bufferIndex = bufferMaxIndex;
+ kr = KERN_RESOURCE_SHORTAGE;
+ } else {
+ kr = KERN_SUCCESS;
+ }
+
+ // Save link register and SP at bottom of stack (used for later fixup).
+ buffer[bufferIndex++] = chudxnu_vm_unslide(currLR, kernel);
+ if (flags & CS_FLAG_EXTRASP) {
+ buffer[bufferIndex++] = chudxnu_vm_unslide(currSP, kernel);
+ }
+ } else {
+ struct arm_saved_state32 *state = NULL;
+ uint32_t *fp = NULL, *nextFramePointer = NULL, *topfp = NULL;
+
+ /* 64-bit kernel stacks, 32-bit user stacks */
+ uint64_t frame[2];
+ uint32_t frame32[2];
+
+ state = saved_state32(sstate);
+
+ /* make sure it is safe to dereference before you do it */
+ kernel = ARM_SUPERVISOR_MODE(state->cpsr);
+
+ /* can't take a kernel callstack if we've got a user frame */
+ if (!user_only && !kernel) {
+ return KERN_FAILURE;
+ }
+
+ /*
+ * Reserve space for saving LR (and sometimes SP) at the end of the
+ * backtrace.
+ */
+ if (flags & CS_FLAG_EXTRASP) {
+ bufferMaxIndex -= 2;
+ } else {
+ bufferMaxIndex -= 1;
+ }
+
+ if (bufferMaxIndex < 2) {
+ *count = 0;
+ return KERN_RESOURCE_SHORTAGE;
+ }
+
+ currPC = (uint64_t)state->pc; /* r15 */
+ if (state->cpsr & PSR_TF) {
+ currPC |= 1ULL; /* encode thumb mode into low bit of PC */
+ }
+ currLR = (uint64_t)state->lr; /* r14 */
+ currSP = (uint64_t)state->sp; /* r13 */
+
+ fp = (uint32_t *)(uintptr_t)state->r[7]; /* frame pointer */
+ topfp = fp;
+
+ bufferIndex = 0; // start with a stack of size zero
+ buffer[bufferIndex++] = chudxnu_vm_unslide(currPC, kernel); // save PC in position 0.
+
+ BUF_VERB(PERF_CS_BACKTRACE | DBG_FUNC_START, kernel, 1);
+
+ // Now, fill buffer with stack backtraces.
+ while (bufferIndex < bufferMaxIndex) {
+ pc = 0ULL;
+ /*
+ * Below the frame pointer, the following values are saved:
+ * -> FP
+ */
+
+ /*
+ * Note that we read the pc even for the first stack frame
+ * (which, in theory, is always empty because the callee fills
+ * it in just before it lowers the stack. However, if we
+ * catch the program in between filling in the return address
+ * and lowering the stack, we want to still have a valid
+ * backtrace. FixupStack correctly disregards this value if
+ * necessary.
+ */
+
+ if ((uint32_t)fp == 0 || ((uint32_t)fp & 0x3) != 0) {
+ /* frame pointer is invalid - stop backtracing */
+ pc = 0ULL;
+ break;
+ }
+
+ if (kernel) {
+ if (((uint32_t)fp > kernStackMax) ||
+ ((uint32_t)fp < kernStackMin)) {
+ kr = KERN_FAILURE;
+ } else {
+ kr = chudxnu_kern_read(&frame,
+ (vm_offset_t)fp,
+ (vm_size_t)sizeof(frame));
+ if (kr == KERN_SUCCESS) {
+ pc = (uint64_t)frame[1];
+ nextFramePointer = (uint32_t *) (frame[0]);
+ } else {
+ pc = 0ULL;
+ nextFramePointer = 0ULL;
+ kr = KERN_FAILURE;
+ }
+ }
+ } else {
+ kr = chudxnu_task_read(task,
+ &frame32,
+ (((uint64_t)(uint32_t)fp) & 0x00000000FFFFFFFFULL),
+ sizeof(frame32));
+ if (kr == KERN_SUCCESS) {
+ pc = (uint64_t)frame32[1];
+ nextFramePointer = (uint32_t *)(uintptr_t)(frame32[0]);
+ } else {
+ pc = 0ULL;
+ nextFramePointer = 0ULL;
+ kr = KERN_FAILURE;
+ }
+ }
+
+ if (kr != KERN_SUCCESS) {
+ pc = 0ULL;
+ break;
+ }
+
+ if (nextFramePointer) {
+ buffer[bufferIndex++] = chudxnu_vm_unslide(pc, kernel);
+ prevPC = pc;
+ }
+
+ if (nextFramePointer < fp) {
+ break;
+ } else {
+ fp = nextFramePointer;
+ }
+ }
+
+ BUF_VERB(PERF_CS_BACKTRACE | DBG_FUNC_END, bufferIndex);
+
+ /* clamp callstack size to max */
+ if (bufferIndex >= bufferMaxIndex) {
+ bufferIndex = bufferMaxIndex;
+ kr = KERN_RESOURCE_SHORTAGE;
+ } else {
+ /* ignore all other failures */
+ kr = KERN_SUCCESS;
+ }
+
+ // Save link register and R13 (sp) at bottom of stack (used for later fixup).
+ buffer[bufferIndex++] = chudxnu_vm_unslide(currLR, kernel);
+ if (flags & CS_FLAG_EXTRASP) {
+ buffer[bufferIndex++] = chudxnu_vm_unslide(currSP, kernel);
+ }
+ }
+
+ *count = bufferIndex;
+ return kr;
+}
+
+kern_return_t
+chudxnu_thread_get_callstack64_kperf(
+ thread_t thread,
+ uint64_t *callStack,
+ mach_msg_type_number_t *count,
+ boolean_t user_only)
+{
+ return chudxnu_thread_get_callstack64_internal( thread, callStack, count, user_only, 0 );
+}
+#elif __x86_64__
+
+#define VALID_STACK_ADDRESS(supervisor, addr, minKernAddr, maxKernAddr) (supervisor ? (addr>=minKernAddr && addr<=maxKernAddr) : TRUE)
+// don't try to read in the hole
+#define VALID_STACK_ADDRESS64(supervisor, addr, minKernAddr, maxKernAddr) \
+(supervisor ? ((uint64_t)addr >= minKernAddr && (uint64_t)addr <= maxKernAddr) : \
+((uint64_t)addr != 0ULL && ((uint64_t)addr <= 0x00007FFFFFFFFFFFULL || (uint64_t)addr >= 0xFFFF800000000000ULL)))
+
+typedef struct _cframe64_t {
+ uint64_t prevFP; // can't use a real pointer here until we're a 64 bit kernel
+ uint64_t caller;
+ uint64_t args[0];
+}cframe64_t;
+
+
+typedef struct _cframe_t {
+ uint32_t prev; // this is really a user32-space pointer to the previous frame
+ uint32_t caller;
+ uint32_t args[0];
+} cframe_t;
+
+extern void * find_user_regs(thread_t);
+extern x86_saved_state32_t *find_kern_regs(thread_t);
+
+static kern_return_t
+do_kernel_backtrace(
+ thread_t thread,
+ struct x86_kernel_state *regs,
+ uint64_t *frames,
+ mach_msg_type_number_t *start_idx,
+ mach_msg_type_number_t max_idx)
+{
+ uint64_t kernStackMin = (uint64_t)thread->kernel_stack;
+ uint64_t kernStackMax = (uint64_t)kernStackMin + kernel_stack_size;
+ mach_msg_type_number_t ct = *start_idx;
+ kern_return_t kr = KERN_FAILURE;
+
+#if __LP64__
+ uint64_t currPC = 0ULL;
+ uint64_t currFP = 0ULL;
+ uint64_t prevPC = 0ULL;
+ uint64_t prevFP = 0ULL;
+ if (KERN_SUCCESS != chudxnu_kern_read(&currPC, (vm_offset_t)&(regs->k_rip), sizeof(uint64_t))) {
+ return KERN_FAILURE;
+ }
+ if (KERN_SUCCESS != chudxnu_kern_read(&currFP, (vm_offset_t)&(regs->k_rbp), sizeof(uint64_t))) {
+ return KERN_FAILURE;
+ }
+#else
+ uint32_t currPC = 0U;
+ uint32_t currFP = 0U;
+ uint32_t prevPC = 0U;
+ uint32_t prevFP = 0U;
+ if (KERN_SUCCESS != chudxnu_kern_read(&currPC, (vm_offset_t)&(regs->k_eip), sizeof(uint32_t))) {
+ return KERN_FAILURE;
+ }
+ if (KERN_SUCCESS != chudxnu_kern_read(&currFP, (vm_offset_t)&(regs->k_ebp), sizeof(uint32_t))) {
+ return KERN_FAILURE;
+ }
+#endif
+
+ if (*start_idx >= max_idx) {
+ return KERN_RESOURCE_SHORTAGE; // no frames traced
+ }
+ if (!currPC) {
+ return KERN_FAILURE;
+ }
+
+ frames[ct++] = chudxnu_vm_unslide((uint64_t)currPC, 1);
+
+ // build a backtrace of this kernel state
+#if __LP64__
+ while (VALID_STACK_ADDRESS64(TRUE, currFP, kernStackMin, kernStackMax)) {
+ // this is the address where caller lives in the user thread
+ uint64_t caller = currFP + sizeof(uint64_t);
+#else
+ while (VALID_STACK_ADDRESS(TRUE, currFP, kernStackMin, kernStackMax)) {
+ uint32_t caller = (uint32_t)currFP + sizeof(uint32_t);
+#endif
+
+ if (!currFP || !currPC) {
+ currPC = 0;
+ break;
+ }
+
+ if (ct >= max_idx) {
+ *start_idx = ct;
+ return KERN_RESOURCE_SHORTAGE;
+ }
+
+ /* read our caller */
+ kr = chudxnu_kern_read(&currPC, (vm_offset_t)caller, sizeof(currPC));
+
+ if (kr != KERN_SUCCESS || !currPC) {
+ currPC = 0UL;
+ break;
+ }
+
+ /*
+ * retrive contents of the frame pointer and advance to the next stack
+ * frame if it's valid
+ */
+ prevFP = 0;
+ kr = chudxnu_kern_read(&prevFP, (vm_offset_t)currFP, sizeof(currPC));
+
+#if __LP64__
+ if (VALID_STACK_ADDRESS64(TRUE, prevFP, kernStackMin, kernStackMax)) {
+#else
+ if (VALID_STACK_ADDRESS(TRUE, prevFP, kernStackMin, kernStackMax)) {
+#endif
+ frames[ct++] = chudxnu_vm_unslide((uint64_t)currPC, 1);
+ prevPC = currPC;
+ }
+ if (prevFP <= currFP) {
+ break;
+ } else {
+ currFP = prevFP;
+ }
+ }
+
+ *start_idx = ct;
+ return KERN_SUCCESS;
+}
+
+
+
+static kern_return_t
+do_backtrace32(
+ task_t task,
+ thread_t thread,
+ x86_saved_state32_t *regs,
+ uint64_t *frames,
+ mach_msg_type_number_t *start_idx,
+ mach_msg_type_number_t max_idx,
+ boolean_t supervisor)
+{
+ uint32_t tmpWord = 0UL;
+ uint64_t currPC = (uint64_t) regs->eip;
+ uint64_t currFP = (uint64_t) regs->ebp;
+ uint64_t prevPC = 0ULL;
+ uint64_t prevFP = 0ULL;
+ uint64_t kernStackMin = thread->kernel_stack;
+ uint64_t kernStackMax = kernStackMin + kernel_stack_size;
+ mach_msg_type_number_t ct = *start_idx;
+ kern_return_t kr = KERN_FAILURE;
+
+ if (ct >= max_idx) {
+ return KERN_RESOURCE_SHORTAGE; // no frames traced
+ }
+ frames[ct++] = chudxnu_vm_unslide(currPC, supervisor);
+
+ // build a backtrace of this 32 bit state.
+ while (VALID_STACK_ADDRESS(supervisor, currFP, kernStackMin, kernStackMax)) {
+ cframe_t *fp = (cframe_t *) (uintptr_t) currFP;
+
+ if (!currFP) {
+ currPC = 0;
+ break;
+ }
+
+ if (ct >= max_idx) {
+ *start_idx = ct;
+ return KERN_RESOURCE_SHORTAGE;
+ }
+
+ /* read our caller */
+ if (supervisor) {
+ kr = chudxnu_kern_read(&tmpWord, (vm_offset_t) &fp->caller, sizeof(uint32_t));
+ } else {
+ kr = chudxnu_task_read(task, &tmpWord, (vm_offset_t) &fp->caller, sizeof(uint32_t));
+ }
+
+ if (kr != KERN_SUCCESS) {
+ currPC = 0ULL;
+ break;
+ }
+
+ currPC = (uint64_t) tmpWord; // promote 32 bit address
+
+ /*
+ * retrive contents of the frame pointer and advance to the next stack
+ * frame if it's valid
+ */
+ prevFP = 0;
+ if (supervisor) {
+ kr = chudxnu_kern_read(&tmpWord, (vm_offset_t)&fp->prev, sizeof(uint32_t));
+ } else {
+ kr = chudxnu_task_read(task, &tmpWord, (vm_offset_t)&fp->prev, sizeof(uint32_t));
+ }
+ prevFP = (uint64_t) tmpWord; // promote 32 bit address
+
+ if (prevFP) {
+ frames[ct++] = chudxnu_vm_unslide(currPC, supervisor);
+ prevPC = currPC;
+ }
+ if (prevFP < currFP) {
+ break;
+ } else {
+ currFP = prevFP;
+ }
+ }
+
+ *start_idx = ct;
+ return KERN_SUCCESS;
+}
+
+static kern_return_t
+do_backtrace64(
+ task_t task,
+ thread_t thread,
+ x86_saved_state64_t *regs,
+ uint64_t *frames,
+ mach_msg_type_number_t *start_idx,
+ mach_msg_type_number_t max_idx,
+ boolean_t supervisor)
+{
+ uint64_t currPC = regs->isf.rip;
+ uint64_t currFP = regs->rbp;
+ uint64_t prevPC = 0ULL;
+ uint64_t prevFP = 0ULL;
+ uint64_t kernStackMin = (uint64_t)thread->kernel_stack;
+ uint64_t kernStackMax = (uint64_t)kernStackMin + kernel_stack_size;
+ mach_msg_type_number_t ct = *start_idx;
+ kern_return_t kr = KERN_FAILURE;
+
+ if (*start_idx >= max_idx) {
+ return KERN_RESOURCE_SHORTAGE; // no frames traced
+ }
+ frames[ct++] = chudxnu_vm_unslide(currPC, supervisor);
+
+ // build a backtrace of this 32 bit state.
+ while (VALID_STACK_ADDRESS64(supervisor, currFP, kernStackMin, kernStackMax)) {
+ // this is the address where caller lives in the user thread
+ uint64_t caller = currFP + sizeof(uint64_t);
+
+ if (!currFP) {
+ currPC = 0;
+ break;
+ }
+
+ if (ct >= max_idx) {
+ *start_idx = ct;
+ return KERN_RESOURCE_SHORTAGE;
+ }
+
+ /* read our caller */
+ if (supervisor) {
+ kr = chudxnu_kern_read(&currPC, (vm_offset_t)caller, sizeof(uint64_t));
+ } else {
+ kr = chudxnu_task_read(task, &currPC, caller, sizeof(uint64_t));
+ }
+
+ if (kr != KERN_SUCCESS) {
+ currPC = 0ULL;
+ break;
+ }
+
+ /*
+ * retrive contents of the frame pointer and advance to the next stack
+ * frame if it's valid
+ */
+ prevFP = 0;
+ if (supervisor) {
+ kr = chudxnu_kern_read(&prevFP, (vm_offset_t)currFP, sizeof(uint64_t));
+ } else {
+ kr = chudxnu_task_read(task, &prevFP, currFP, sizeof(uint64_t));
+ }
+
+ if (VALID_STACK_ADDRESS64(supervisor, prevFP, kernStackMin, kernStackMax)) {
+ frames[ct++] = chudxnu_vm_unslide(currPC, supervisor);
+ prevPC = currPC;
+ }
+ if (prevFP < currFP) {
+ break;
+ } else {
+ currFP = prevFP;
+ }
+ }
+
+ *start_idx = ct;
+ return KERN_SUCCESS;
+}
+
+static kern_return_t
+chudxnu_thread_get_callstack64_internal(
+ thread_t thread,
+ uint64_t *callstack,
+ mach_msg_type_number_t *count,
+ boolean_t user_only,
+ boolean_t kern_only)
+{
+ kern_return_t kr = KERN_FAILURE;
+ task_t task = thread->task;
+ uint64_t currPC = 0ULL;
+ boolean_t supervisor = FALSE;
+ mach_msg_type_number_t bufferIndex = 0;
+ mach_msg_type_number_t bufferMaxIndex = *count;
+ x86_saved_state_t *tagged_regs = NULL; // kernel register state
+ x86_saved_state64_t *regs64 = NULL;
+ x86_saved_state32_t *regs32 = NULL;
+ x86_saved_state32_t *u_regs32 = NULL;
+ x86_saved_state64_t *u_regs64 = NULL;
+ struct x86_kernel_state *kregs = NULL;
+
+ if (ml_at_interrupt_context()) {
+ if (user_only) {
+ /* can't backtrace user state on interrupt stack. */
+ return KERN_FAILURE;
+ }
+
+ /* backtracing at interrupt context? */
+ if (thread == current_thread() && current_cpu_datap()->cpu_int_state) {
+ /*
+ * Locate the registers for the interrupted thread, assuming it is
+ * current_thread().
+ */
+ tagged_regs = current_cpu_datap()->cpu_int_state;
+
+ if (is_saved_state64(tagged_regs)) {
+ /* 64 bit registers */
+ regs64 = saved_state64(tagged_regs);
+ supervisor = ((regs64->isf.cs & SEL_PL) != SEL_PL_U);
+ } else {
+ /* 32 bit registers */
+ regs32 = saved_state32(tagged_regs);
+ supervisor = ((regs32->cs & SEL_PL) != SEL_PL_U);
+ }
+ }
+ }
+
+ if (!ml_at_interrupt_context() && kernel_task == task) {
+ if (!thread->kernel_stack) {
+ return KERN_FAILURE;
+ }
+
+ // Kernel thread not at interrupt context
+ kregs = (struct x86_kernel_state *)NULL;
+
+ // nofault read of the thread->kernel_stack pointer
+ if (KERN_SUCCESS != chudxnu_kern_read(&kregs, (vm_offset_t)&(thread->kernel_stack), sizeof(void *))) {
+ return KERN_FAILURE;
+ }
+
+ // Adjust to find the saved kernel state
+ kregs = STACK_IKS((vm_offset_t)(uintptr_t)kregs);
+
+ supervisor = TRUE;
+ } else if (!tagged_regs) {
+ /*
+ * not at interrupt context, or tracing a different thread than
+ * current_thread() at interrupt context
+ */
+ tagged_regs = USER_STATE(thread);
+ if (is_saved_state64(tagged_regs)) {
+ /* 64 bit registers */
+ regs64 = saved_state64(tagged_regs);
+ supervisor = ((regs64->isf.cs & SEL_PL) != SEL_PL_U);
+ } else {
+ /* 32 bit registers */
+ regs32 = saved_state32(tagged_regs);
+ supervisor = ((regs32->cs & SEL_PL) != SEL_PL_U);
+ }
+ }
+
+ *count = 0;
+
+ if (supervisor) {
+ // the caller only wants a user callstack.
+ if (user_only) {
+ // bail - we've only got kernel state
+ return KERN_FAILURE;
+ }
+ } else {
+ // regs32(64) is not in supervisor mode.
+ u_regs32 = regs32;
+ u_regs64 = regs64;
+ regs32 = NULL;
+ regs64 = NULL;
+ }
+
+ if (user_only) {
+ /* we only want to backtrace the user mode */
+ if (!(u_regs32 || u_regs64)) {
+ /* no user state to look at */
+ return KERN_FAILURE;
+ }
+ }
+
+ /*
+ * Order of preference for top of stack:
+ * 64 bit kernel state (not likely)
+ * 32 bit kernel state
+ * 64 bit user land state
+ * 32 bit user land state
+ */
+
+ if (kregs) {
+ /*
+ * nofault read of the registers from the kernel stack (as they can
+ * disappear on the fly).
+ */
+
+ if (KERN_SUCCESS != chudxnu_kern_read(&currPC, (vm_offset_t)&(kregs->k_rip), sizeof(uint64_t))) {
+ return KERN_FAILURE;
+ }
+ } else if (regs64) {
+ currPC = regs64->isf.rip;
+ } else if (regs32) {
+ currPC = (uint64_t) regs32->eip;
+ } else if (u_regs64) {
+ currPC = u_regs64->isf.rip;
+ } else if (u_regs32) {
+ currPC = (uint64_t) u_regs32->eip;
+ }
+
+ if (!currPC) {
+ /* no top of the stack, bail out */
+ return KERN_FAILURE;
+ }
+
+ bufferIndex = 0;
+
+ if (bufferMaxIndex < 1) {
+ *count = 0;
+ return KERN_RESOURCE_SHORTAGE;
+ }
+
+ /* backtrace kernel */
+ if (kregs) {
+ addr64_t address = 0ULL;
+ size_t size = 0UL;
+
+ // do the backtrace
+ kr = do_kernel_backtrace(thread, kregs, callstack, &bufferIndex, bufferMaxIndex);
+
+ // and do a nofault read of (r|e)sp
+ uint64_t rsp = 0ULL;
+ size = sizeof(uint64_t);
+
+ if (KERN_SUCCESS != chudxnu_kern_read(&address, (vm_offset_t)&(kregs->k_rsp), size)) {
+ address = 0ULL;
+ }
+
+ if (address && KERN_SUCCESS == chudxnu_kern_read(&rsp, (vm_offset_t)address, size) && bufferIndex < bufferMaxIndex) {
+ callstack[bufferIndex++] = (uint64_t)rsp;
+ }
+ } else if (regs64) {
+ uint64_t rsp = 0ULL;
+
+ // backtrace the 64bit side.
+ kr = do_backtrace64(task, thread, regs64, callstack, &bufferIndex,
+ bufferMaxIndex - 1, TRUE);
+
+ if (KERN_SUCCESS == chudxnu_kern_read(&rsp, (vm_offset_t) regs64->isf.rsp, sizeof(uint64_t)) &&
+ bufferIndex < bufferMaxIndex) {
+ callstack[bufferIndex++] = rsp;
+ }
+ } else if (regs32) {
+ uint32_t esp = 0UL;
+
+ // backtrace the 32bit side.
+ kr = do_backtrace32(task, thread, regs32, callstack, &bufferIndex,
+ bufferMaxIndex - 1, TRUE);
+
+ if (KERN_SUCCESS == chudxnu_kern_read(&esp, (vm_offset_t) regs32->uesp, sizeof(uint32_t)) &&
+ bufferIndex < bufferMaxIndex) {
+ callstack[bufferIndex++] = (uint64_t) esp;
+ }
+ } else if (u_regs64 && !kern_only) {
+ /* backtrace user land */
+ uint64_t rsp = 0ULL;
+
+ kr = do_backtrace64(task, thread, u_regs64, callstack, &bufferIndex,
+ bufferMaxIndex - 1, FALSE);
+
+ if (KERN_SUCCESS == chudxnu_task_read(task, &rsp, (addr64_t) u_regs64->isf.rsp, sizeof(uint64_t)) &&
+ bufferIndex < bufferMaxIndex) {
+ callstack[bufferIndex++] = rsp;
+ }
+ } else if (u_regs32 && !kern_only) {
+ uint32_t esp = 0UL;
+
+ kr = do_backtrace32(task, thread, u_regs32, callstack, &bufferIndex,
+ bufferMaxIndex - 1, FALSE);
+
+ if (KERN_SUCCESS == chudxnu_task_read(task, &esp, (addr64_t) u_regs32->uesp, sizeof(uint32_t)) &&
+ bufferIndex < bufferMaxIndex) {
+ callstack[bufferIndex++] = (uint64_t) esp;
+ }
+ }
+
+ *count = bufferIndex;
+ return kr;
+}
+
+__private_extern__
+kern_return_t
+chudxnu_thread_get_callstack64_kperf(
+ thread_t thread,
+ uint64_t *callstack,
+ mach_msg_type_number_t *count,
+ boolean_t is_user)
+{
+ return chudxnu_thread_get_callstack64_internal(thread, callstack, count, is_user, !is_user);
+}
+#else /* !__arm__ && !__arm64__ && !__x86_64__ */
+#error kperf: unsupported architecture
+#endif /* !__arm__ && !__arm64__ && !__x86_64__ */
projects / apple / xnu.git / blobdiff