]> git.saurik.com Git - apple/xnu.git/blobdiff - bsd/dev/i386/fbt_x86.c
xnu-2782.10.72.tar.gz
[apple/xnu.git] / bsd / dev / i386 / fbt_x86.c
index 19d461ac269861c0d54f22992e890307ae0d1759..93c19c56113d63e351521c3924a0c8619cf21d7e 100644 (file)
@@ -39,6 +39,7 @@
 #include <mach-o/loader.h> 
 #include <mach-o/nlist.h>
 #include <libkern/kernel_mach_header.h>
+#include <libkern/OSAtomic.h>
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -101,7 +102,9 @@ extern dtrace_provider_id_t fbt_id;
 extern fbt_probe_t             **fbt_probetab;
 extern int                     fbt_probetab_mask;
 
-kern_return_t fbt_perfCallback(int, x86_saved_state_t *, __unused int, __unused int);
+extern int                     gIgnoreFBTBlacklist; /* From fbt_init */
+
+kern_return_t fbt_perfCallback(int, x86_saved_state_t *, uintptr_t *, __unused int);
 
 /*
  * Critical routines that must not be probed. PR_5221096, PR_5379018.
@@ -144,6 +147,7 @@ static const char * critical_blacklist[] =
        "cpu_topology_start_cpu",       
        "cpu_type", 
        "cpuid_cpu_display",
+       "cpuid_extfeatures",
        "handle_pending_TLB_flushes",
        "hw_compare_and_store",
        "machine_idle_cstate",
@@ -171,8 +175,8 @@ static const char * probe_ctx_closure[] =
        "IS_64BIT_PROCESS",
        "OSCompareAndSwap",
        "absolutetime_to_microtime",
+       "act_set_astbsd",
        "ast_pending",
-       "astbsd_on",
        "clock_get_calendar_nanotime_nowait",
        "copyin",
        "copyin_user",
@@ -213,8 +217,6 @@ static const char * probe_ctx_closure[] =
        "prf",
        "proc_is64bit",
        "proc_selfname",
-       "proc_selfpid",
-       "proc_selfppid",
        "psignal_lock",
        "rtc_nanotime_load",
        "rtc_nanotime_read",
@@ -257,42 +259,260 @@ static const void * bsearch(
        return (NULL);
 }
 
-#if defined(__i386__)
+/*
+ * Module validation
+ */ 
+static int
+is_module_valid(struct modctl* ctl)
+{
+       ASSERT(!MOD_FBT_PROBES_PROVIDED(ctl));
+       ASSERT(!MOD_FBT_INVALID(ctl));
+       
+       if (0 == ctl->mod_address || 0 == ctl->mod_size) {
+               return FALSE;
+       }
+       
+       if (0 == ctl->mod_loaded) {
+               return FALSE;
+       }
+       
+       if (strstr(ctl->mod_modname, "CHUD") != NULL)
+               return FALSE;
+       
+        /*
+        * If the user sets this, trust they know what they are doing.
+        */
+       if (gIgnoreFBTBlacklist)   /* per boot-arg set in fbt_init() */
+               return TRUE;
+
+       /*
+        * These drivers control low level functions that when traced
+        * cause problems often in the sleep/wake paths as well as 
+        * critical debug and panic paths.
+        * If somebody really wants to drill in on one of these kexts, then
+        * they can override blacklisting using the boot-arg above.
+        */
+
+       if (strstr(ctl->mod_modname, "AppleACPIEC") != NULL)
+               return FALSE;
+
+       if (strstr(ctl->mod_modname, "AppleACPIPlatform") != NULL)
+               return FALSE;   
+
+       if (strstr(ctl->mod_modname, "AppleRTC") != NULL)
+               return FALSE;
+
+       if (strstr(ctl->mod_modname, "IOACPIFamily") != NULL)
+               return FALSE;
+
+       if (strstr(ctl->mod_modname, "AppleIntelCPUPowerManagement") != NULL)
+               return FALSE;
+       
+       if (strstr(ctl->mod_modname, "AppleProfile") != NULL)
+               return FALSE;
+
+       if (strstr(ctl->mod_modname, "AppleIntelProfile") != NULL)
+               return FALSE;
+
+       if (strstr(ctl->mod_modname, "AppleEFI") != NULL)
+               return FALSE;
+
+       return TRUE;
+}
+
+/*
+ * FBT probe name validation
+ */
+static int
+is_symbol_valid(const char* name)
+{
+       /*
+        * If the user set this, trust they know what they are doing.
+        */
+       if (gIgnoreFBTBlacklist)
+               return TRUE;
+               
+       if (LIT_STRNSTART(name, "dtrace_") && !LIT_STRNSTART(name, "dtrace_safe_")) {
+               /*
+                * Anything beginning with "dtrace_" may be called
+                * from probe context unless it explitly indicates
+                * that it won't be called from probe context by
+                * using the prefix "dtrace_safe_".
+                */
+               return FALSE;
+       }
+       
+       if (LIT_STRNSTART(name, "fasttrap_") ||
+           LIT_STRNSTART(name, "fuword") ||
+           LIT_STRNSTART(name, "suword") ||
+           LIT_STRNEQL(name, "sprlock") ||
+           LIT_STRNEQL(name, "sprunlock") ||
+           LIT_STRNEQL(name, "uread") ||
+           LIT_STRNEQL(name, "uwrite")) {
+               return FALSE; /* Fasttrap inner-workings. */
+       }
+       
+       if (LIT_STRNSTART(name, "dsmos_")) 
+               return FALSE; /* Don't Steal Mac OS X! */
+       
+        if (LIT_STRNSTART(name, "_dtrace"))
+               return FALSE; /* Shims in dtrace.c */
+       
+       if (LIT_STRNSTART(name, "chud"))
+               return FALSE; /* Professional courtesy. */
+       
+       if (LIT_STRNSTART(name, "hibernate_"))
+               return FALSE; /* Let sleeping dogs lie. */
+
+       if (LIT_STRNEQL(name, "_ZNK6OSData14getBytesNoCopyEv"))
+               return FALSE;  /* Data::getBytesNoCopy, IOHibernateSystemWake path */
+       
+       if (LIT_STRNEQL(name, "_ZN9IOService14newTemperatureElPS_") || /* IOService::newTemperature */
+           LIT_STRNEQL(name, "_ZN9IOService26temperatureCriticalForZoneEPS_")) { /* IOService::temperatureCriticalForZone */
+               return FALSE; /* Per the fire code */
+       }
+       
+       /*
+        * Place no probes (illegal instructions) in the exception handling path!
+        */
+       if (LIT_STRNEQL(name, "t_invop") ||
+           LIT_STRNEQL(name, "enter_lohandler") ||
+           LIT_STRNEQL(name, "lo_alltraps") ||
+           LIT_STRNEQL(name, "kernel_trap") ||
+           LIT_STRNEQL(name, "interrupt") ||             
+           LIT_STRNEQL(name, "i386_astintr")) {
+               return FALSE;
+       }
+       
+       if (LIT_STRNEQL(name, "current_thread") ||
+           LIT_STRNEQL(name, "ast_pending") ||
+           LIT_STRNEQL(name, "fbt_perfCallback") ||
+           LIT_STRNEQL(name, "machine_thread_get_kern_state") ||
+           LIT_STRNEQL(name, "get_threadtask") ||
+           LIT_STRNEQL(name, "ml_set_interrupts_enabled") ||
+           LIT_STRNEQL(name, "dtrace_invop") ||
+           LIT_STRNEQL(name, "fbt_invop") ||
+           LIT_STRNEQL(name, "sdt_invop") ||
+           LIT_STRNEQL(name, "max_valid_stack_address")) {
+               return FALSE;
+       }
+       
+       /*
+        * Voodoo.
+        */
+       if (LIT_STRNSTART(name, "machine_stack_") ||
+           LIT_STRNSTART(name, "mapping_") ||
+           LIT_STRNEQL(name, "tmrCvt") ||
+           
+           LIT_STRNSTART(name, "tsc_") ||
+           
+           LIT_STRNSTART(name, "pmCPU") ||
+           LIT_STRNEQL(name, "pmKextRegister") ||
+           LIT_STRNEQL(name, "pmMarkAllCPUsOff") ||
+           LIT_STRNEQL(name, "pmSafeMode") ||
+           LIT_STRNEQL(name, "pmTimerSave") ||
+           LIT_STRNEQL(name, "pmTimerRestore") ||
+           LIT_STRNEQL(name, "pmUnRegister") ||
+           LIT_STRNSTART(name, "pms") ||
+           LIT_STRNEQL(name, "power_management_init") ||
+           LIT_STRNSTART(name, "usimple_") ||
+           LIT_STRNSTART(name, "lck_spin_lock") ||
+           LIT_STRNSTART(name, "lck_spin_unlock") ||             
+           
+           LIT_STRNSTART(name, "rtc_") ||
+           LIT_STRNSTART(name, "_rtc_") ||
+           LIT_STRNSTART(name, "rtclock_") ||
+           LIT_STRNSTART(name, "clock_") ||
+           LIT_STRNSTART(name, "absolutetime_to_") ||
+           LIT_STRNEQL(name, "setPop") ||
+           LIT_STRNEQL(name, "nanoseconds_to_absolutetime") ||
+           LIT_STRNEQL(name, "nanotime_to_absolutetime") ||
+           
+           LIT_STRNSTART(name, "etimer_") ||
+           
+           LIT_STRNSTART(name, "commpage_") ||
+           LIT_STRNSTART(name, "pmap_") ||
+           LIT_STRNSTART(name, "ml_") ||
+           LIT_STRNSTART(name, "PE_") ||
+           LIT_STRNEQL(name, "kprintf") ||
+           LIT_STRNSTART(name, "lapic_") ||
+           LIT_STRNSTART(name, "act_machine") ||
+           LIT_STRNSTART(name, "acpi_")  ||
+           LIT_STRNSTART(name, "pal_")){
+               return FALSE;
+       }
+
+       /*
+         * Avoid machine_ routines. PR_5346750.
+         */
+        if (LIT_STRNSTART(name, "machine_"))
+               return FALSE;
+       
+       if (LIT_STRNEQL(name, "handle_pending_TLB_flushes"))
+               return FALSE;
+       
+        /*
+         * Place no probes on critical routines. PR_5221096
+         */
+        if (bsearch( name, critical_blacklist, CRITICAL_BLACKLIST_COUNT, sizeof(name), _cmp ) != NULL)
+                return FALSE;
+       
+        /*
+        * Place no probes that could be hit in probe context.
+        */
+       if (bsearch( name, probe_ctx_closure, PROBE_CTX_CLOSURE_COUNT, sizeof(name), _cmp ) != NULL) {
+               return FALSE;
+       }
+       
+       /*
+        * Place no probes that could be hit on the way to the debugger.
+        */
+       if (LIT_STRNSTART(name, "kdp_") ||
+           LIT_STRNSTART(name, "kdb_") ||
+           LIT_STRNSTART(name, "kdbg_") ||
+           LIT_STRNSTART(name, "kdebug_") ||
+           LIT_STRNSTART(name, "kernel_debug") ||
+           LIT_STRNSTART(name, "debug_") ||
+           LIT_STRNEQL(name, "Debugger") ||
+           LIT_STRNEQL(name, "Call_DebuggerC") ||
+           LIT_STRNEQL(name, "lock_debugger") ||
+           LIT_STRNEQL(name, "unlock_debugger") ||
+           LIT_STRNEQL(name, "packA")  ||
+           LIT_STRNEQL(name, "unpackA")  ||
+           LIT_STRNEQL(name, "SysChoked"))  {
+               return FALSE;
+       }
+       
+       
+       /*
+        * Place no probes that could be hit on the way to a panic.
+        */
+       if (NULL != strstr(name, "panic_") ||
+           LIT_STRNEQL(name, "panic") ||
+           LIT_STRNEQL(name, "preemption_underflow_panic")) {
+               return FALSE;
+       }
+       
+       return TRUE;
+}
+
 int
-fbt_invop(uintptr_t addr, uintptr_t *stack, uintptr_t rval)
+fbt_invop(uintptr_t addr, uintptr_t *state, uintptr_t rval)
 {
-       uintptr_t stack0 = 0, stack1 = 0, stack2 = 0, stack3 = 0, stack4 = 0;
        fbt_probe_t *fbt = fbt_probetab[FBT_ADDR2NDX(addr)];
-
+       
        for (; fbt != NULL; fbt = fbt->fbtp_hashnext) {
                if ((uintptr_t)fbt->fbtp_patchpoint == addr) {
 
                        if (fbt->fbtp_roffset == 0) {
-                               uintptr_t *stacktop;
-                               if (CPU_ON_INTR(CPU))
-                                       stacktop = (uintptr_t *)dtrace_get_cpu_int_stack_top();
-                               else
-                                       stacktop = (uintptr_t *)(dtrace_get_kernel_stack(current_thread()) + kernel_stack_size);
-
-                               stack += 1; /* skip over the target's pushl'd %ebp */
-
-                               if (stack <= stacktop)
-                                       CPU->cpu_dtrace_caller = *stack++;
-                               if (stack <= stacktop)
-                                       stack0 = *stack++;
-                               if (stack <= stacktop)
-                                       stack1 = *stack++;
-                               if (stack <= stacktop)
-                                       stack2 = *stack++;
-                               if (stack <= stacktop)
-                                       stack3 = *stack++;
-                               if (stack <= stacktop)
-                                       stack4 = *stack++;
-
-                               /* 32-bit ABI, arguments passed on stack. */
-                               dtrace_probe(fbt->fbtp_id, stack0, stack1, stack2, stack3, stack4);
+                               x86_saved_state64_t *regs = (x86_saved_state64_t *)state;
+
+                               CPU->cpu_dtrace_caller = *(uintptr_t *)(((uintptr_t)(regs->isf.rsp))+sizeof(uint64_t)); // 8(%rsp)
+                               /* 64-bit ABI, arguments passed in registers. */
+                               dtrace_probe(fbt->fbtp_id, regs->rdi, regs->rsi, regs->rdx, regs->rcx, regs->r8);
                                CPU->cpu_dtrace_caller = 0;
                        } else {
+
                                dtrace_probe(fbt->fbtp_id, fbt->fbtp_roffset, rval, 0, 0, 0);
                                CPU->cpu_dtrace_caller = 0;
                        }
@@ -304,7 +524,7 @@ fbt_invop(uintptr_t addr, uintptr_t *stack, uintptr_t rval)
        return (0);
 }
 
-#define IS_USER_TRAP(regs) (regs && (((regs)->cs & 3) != 0))
+#define IS_USER_TRAP(regs) (regs && (((regs)->isf.cs & 3) != 0))
 #define T_INVALID_OPCODE 6
 #define FBT_EXCEPTION_CODE T_INVALID_OPCODE
 #define T_PREEMPT       255
@@ -313,93 +533,95 @@ kern_return_t
 fbt_perfCallback(
                 int                    trapno,
                 x86_saved_state_t      *tagged_regs,
-                __unused int        unused1,
+               uintptr_t               *lo_spp,
                 __unused int        unused2)
 {
        kern_return_t retval = KERN_FAILURE;
-       x86_saved_state32_t *saved_state = saved_state32(tagged_regs);
-       struct x86_saved_state32_from_kernel *regs = (struct x86_saved_state32_from_kernel *)saved_state;
+       x86_saved_state64_t *saved_state = saved_state64(tagged_regs);
 
        if (FBT_EXCEPTION_CODE == trapno && !IS_USER_TRAP(saved_state)) {
-               boolean_t oldlevel, cpu_64bit;
-               uint32_t esp_probe, *ebp, edi, fp, *pDst, delta = 0;
+               boolean_t oldlevel;
+               uint64_t rsp_probe, fp, delta = 0;
+               uintptr_t old_sp;
+               uint32_t *pDst;
                int emul;
 
-               cpu_64bit = ml_is64bit();
+
                oldlevel = ml_set_interrupts_enabled(FALSE);
 
                /* Calculate where the stack pointer was when the probe instruction "fired." */
-               if (cpu_64bit) {
-                       esp_probe = saved_state->uesp; /* Easy, x86_64 establishes this value in idt64.s */
-               } else {
-                       esp_probe = (uint32_t)&(regs[1]); /* Nasty, infer the location above the save area */
-               }
+               rsp_probe = saved_state->isf.rsp; /* Easy, x86_64 establishes this value in idt64.s */
 
-               emul = dtrace_invop( saved_state->eip, (uintptr_t *)esp_probe, saved_state->eax );
-               __asm__ volatile(".globl _dtrace_invop_callsite");
-               __asm__ volatile("_dtrace_invop_callsite:");
+               __asm__ volatile(
+                       "Ldtrace_invop_callsite_pre_label:\n"
+                       ".data\n"
+                       ".private_extern _dtrace_invop_callsite_pre\n"
+                       "_dtrace_invop_callsite_pre:\n"
+                       "  .quad Ldtrace_invop_callsite_pre_label\n"
+                       ".text\n"
+                                );
+
+               emul = dtrace_invop( saved_state->isf.rip, (uintptr_t *)saved_state, saved_state->rax );
+
+               __asm__ volatile(
+                       "Ldtrace_invop_callsite_post_label:\n"
+                       ".data\n"
+                       ".private_extern _dtrace_invop_callsite_post\n"
+                       "_dtrace_invop_callsite_post:\n"
+                       "  .quad Ldtrace_invop_callsite_post_label\n"
+                       ".text\n"
+                                );             
 
                switch (emul) {
                case DTRACE_INVOP_NOP:
-                       saved_state->eip += DTRACE_INVOP_NOP_SKIP;      /* Skip over the patched NOP (planted by sdt.) */
+                       saved_state->isf.rip += DTRACE_INVOP_NOP_SKIP;  /* Skip over the patched NOP (planted by sdt). */
                        retval = KERN_SUCCESS;
                        break;
 
-               case DTRACE_INVOP_MOVL_ESP_EBP:
-                       saved_state->ebp = esp_probe;                                           /* Emulate patched movl %esp,%ebp */
-                       saved_state->eip += DTRACE_INVOP_MOVL_ESP_EBP_SKIP;     /* Skip over the bytes of the patched movl %esp,%ebp */
+               case DTRACE_INVOP_MOV_RSP_RBP:
+                       saved_state->rbp = rsp_probe;                                                   /* Emulate patched mov %rsp,%rbp */
+                       saved_state->isf.rip += DTRACE_INVOP_MOV_RSP_RBP_SKIP;  /* Skip over the bytes of the patched mov %rsp,%rbp */
                        retval = KERN_SUCCESS;
                        break;
 
-               case DTRACE_INVOP_POPL_EBP:
+               case DTRACE_INVOP_POP_RBP:
                case DTRACE_INVOP_LEAVE:
 /*
- * Emulate first micro-op of patched leave: movl %ebp,%esp
+ * Emulate first micro-op of patched leave: mov %rbp,%rsp
  * fp points just below the return address slot for target's ret 
  * and at the slot holding the frame pointer saved by the target's prologue.
  */
-                       fp = saved_state->ebp;
-/* Emulate second micro-op of patched leave: patched popl %ebp
- * savearea ebp is set for the frame of the caller to target
- * The *live* %esp will be adjusted below for pop increment(s)
+                       fp = saved_state->rbp;
+/* Emulate second micro-op of patched leave: patched pop %rbp
+ * savearea rbp is set for the frame of the caller to target
+ * The *live* %rsp will be adjusted below for pop increment(s)
  */
-                       saved_state->ebp = *(uint32_t *)fp;
+                       saved_state->rbp = *(uint64_t *)fp;
 /* Skip over the patched leave */
-                       saved_state->eip += DTRACE_INVOP_LEAVE_SKIP;
+                       saved_state->isf.rip += DTRACE_INVOP_LEAVE_SKIP;
 /*
  * Lift the stack to account for the emulated leave
  * Account for words local in this frame
  * (in "case DTRACE_INVOP_POPL_EBP:" this is zero.)
  */
-                       delta = ((uint32_t *)fp) - ((uint32_t *)esp_probe);
-/* Account for popping off the ebp (just accomplished by the emulation
+                       delta = ((uint32_t *)fp) - ((uint32_t *)rsp_probe); /* delta is a *word* increment */
+/* Account for popping off the rbp (just accomplished by the emulation
  * above...)
  */
-                       delta += 1;
-                       
-                       if (cpu_64bit)
-                               saved_state->uesp += (delta << 2);
-
-/* XXX Fragile in the extreme. Obtain the value of %edi that our caller pushed
- * (on behalf of its caller -- trap_from_kernel()). Ultimately,
- * trap_from_kernel's stack pointer is restored from this slot.
- * This is sensitive to the manner in which the compiler preserves %edi,
- * and trap_from_kernel()'s internals.
- */
-                       ebp = (uint32_t *)__builtin_frame_address(0);
-                       ebp = (uint32_t *)*ebp;
-                       edi = *(ebp - 1);
+                       delta += 2;
+                       saved_state->isf.rsp += (delta << 2);
+/* Obtain the stack pointer recorded by the trampolines */
+                       old_sp = *lo_spp;
 /* Shift contents of stack */
                        for (pDst = (uint32_t *)fp;
-                            pDst > (((uint32_t *)edi));
+                            pDst > (((uint32_t *)old_sp));
                                 pDst--)
                                *pDst = pDst[-delta];
 
 /* Track the stack lift in "saved_state". */
-                       saved_state = (x86_saved_state32_t *) (((uintptr_t)saved_state) + (delta << 2));
-
-/* Now adjust the value of %edi in our caller (kernel_trap)'s frame */
-                       *(ebp - 1) = edi + (delta << 2);
+                       saved_state = (x86_saved_state64_t *) (((uintptr_t)saved_state) + (delta << 2));
+/* Adjust the stack pointer utilized by the trampolines */
+                       *lo_spp = old_sp + (delta << 2);
 
                        retval = KERN_SUCCESS;
                        break;
@@ -408,7 +630,7 @@ fbt_perfCallback(
                        retval = KERN_FAILURE;
                        break;
                }
-               saved_state->trapno = T_PREEMPT; /* Avoid call to i386_astintr()! */
+               saved_state->isf.trapno = T_PREEMPT; /* Avoid call to i386_astintr()! */
 
                ml_set_interrupts_enabled(oldlevel);
        }
@@ -418,47 +640,301 @@ fbt_perfCallback(
 
 /*ARGSUSED*/
 static void
-__fbt_provide_module(void *arg, struct modctl *ctl)
+__provide_probe_64(struct modctl *ctl, uintptr_t instrLow, uintptr_t instrHigh, char *modname, char* symbolName, machine_inst_t* symbolStart)
 {
-#pragma unused(arg)
-       kernel_mach_header_t            *mh;
-       struct load_command         *cmd;
-       kernel_segment_command_t        *orig_ts = NULL, *orig_le = NULL;
-       struct symtab_command       *orig_st = NULL;
-       struct nlist                *sym = NULL;
-       char                                            *strings;
-       uintptr_t                                       instrLow, instrHigh;
-       char                                            *modname;
-       unsigned int                            i, j;
-
-       int gIgnoreFBTBlacklist = 0;
-       PE_parse_boot_argn("IgnoreFBTBlacklist", &gIgnoreFBTBlacklist, sizeof (gIgnoreFBTBlacklist));
+       unsigned int                    j;
+       unsigned int                    doenable = 0;
+       dtrace_id_t                     thisid;
 
-       mh = (kernel_mach_header_t *)(ctl->address);
-       modname = ctl->mod_modname;
-
-       if (0 == ctl->address || 0 == ctl->size) /* Has the linker been jettisoned? */
+       fbt_probe_t *newfbt, *retfbt, *entryfbt;
+       machine_inst_t *instr, *limit, theInstr, i1, i2, i3;
+       int size;
+               
+       for (j = 0, instr = symbolStart, theInstr = 0;
+            (j < 4) && ((uintptr_t)instr >= instrLow) && (instrHigh > (uintptr_t)(instr + 2)); 
+            j++) {
+               theInstr = instr[0];
+               if (theInstr == FBT_PUSH_RBP || theInstr == FBT_RET || theInstr == FBT_RET_IMM16)
+                       break;
+               
+               if ((size = dtrace_instr_size(instr)) <= 0)
+                       break;
+               
+               instr += size;
+       }
+       
+       if (theInstr != FBT_PUSH_RBP)
                return;
-
+       
+       i1 = instr[1];
+       i2 = instr[2];
+       i3 = instr[3];
+       
+       limit = (machine_inst_t *)instrHigh;
+       
+       if (i1 == FBT_REX_RSP_RBP && i2 == FBT_MOV_RSP_RBP0 && i3 == FBT_MOV_RSP_RBP1) {
+               instr += 1; /* Advance to the mov %rsp,%rbp */
+               theInstr = i1;
+       } else {
+               return;
+       }
+#if 0
+       else {
+               /*
+                * Sometimes, the compiler will schedule an intervening instruction
+                * in the function prologue. Example:
+                *
+                * _mach_vm_read:
+                * 000006d8        pushl   %ebp
+                * 000006d9        movl    $0x00000004,%edx
+                * 000006de        movl    %esp,%ebp
+                * 
+                * Try the next instruction, to see if it is a movl %esp,%ebp
+                */
+               
+               instr += 1; /* Advance past the pushl %ebp */
+               if ((size = dtrace_instr_size(instr)) <= 0)
+                       return;
+               
+               instr += size;
+               
+               if ((instr + 1) >= limit)
+                       return;
+               
+               i1 = instr[0];
+               i2 = instr[1];
+               
+               if (!(i1 == FBT_MOVL_ESP_EBP0_V0 && i2 == FBT_MOVL_ESP_EBP1_V0) &&
+                   !(i1 == FBT_MOVL_ESP_EBP0_V1 && i2 == FBT_MOVL_ESP_EBP1_V1))
+                       return;
+               
+               /* instr already points at the movl %esp,%ebp */
+               theInstr = i1;
+       }
+#endif
+       thisid = dtrace_probe_lookup(fbt_id, modname, symbolName, FBT_ENTRY);
+       newfbt = kmem_zalloc(sizeof (fbt_probe_t), KM_SLEEP);
+       strlcpy( (char *)&(newfbt->fbtp_name), symbolName, MAX_FBTP_NAME_CHARS );
+       
+       if (thisid != 0) {
+               /*
+                * The dtrace_probe previously existed, so we have to hook
+                * the newfbt entry onto the end of the existing fbt's chain.
+                * If we find an fbt entry that was previously patched to
+                * fire, (as indicated by the current patched value), then
+                * we want to enable this newfbt on the spot.
+                */
+               entryfbt = dtrace_probe_arg (fbt_id, thisid);
+               ASSERT (entryfbt != NULL);
+               for(; entryfbt != NULL; entryfbt = entryfbt->fbtp_next) {
+                       if (entryfbt->fbtp_currentval == entryfbt->fbtp_patchval)
+                               doenable++;
+                       
+                       if (entryfbt->fbtp_next == NULL) {
+                               entryfbt->fbtp_next = newfbt;
+                               newfbt->fbtp_id = entryfbt->fbtp_id;
+                               break;
+                       }
+               }                   
+       }
+       else {
+               /*
+                * The dtrace_probe did not previously exist, so we
+                * create it and hook in the newfbt.  Since the probe is
+                * new, we obviously do not need to enable it on the spot.
+                */
+               newfbt->fbtp_id = dtrace_probe_create(fbt_id, modname, symbolName, FBT_ENTRY, FBT_AFRAMES_ENTRY, newfbt);
+               doenable = 0;
+       }
+       
+       newfbt->fbtp_patchpoint = instr;
+       newfbt->fbtp_ctl = ctl;
+       newfbt->fbtp_loadcnt = ctl->mod_loadcnt;
+       newfbt->fbtp_rval = DTRACE_INVOP_MOV_RSP_RBP;
+       newfbt->fbtp_savedval = theInstr;
+       newfbt->fbtp_patchval = FBT_PATCHVAL;
+       newfbt->fbtp_currentval = 0;
+       newfbt->fbtp_hashnext = fbt_probetab[FBT_ADDR2NDX(instr)];
+       fbt_probetab[FBT_ADDR2NDX(instr)] = newfbt;
+       
+       if (doenable)
+               fbt_enable(NULL, newfbt->fbtp_id, newfbt);
+       
        /*
-        * Employees of dtrace and their families are ineligible.  Void
-        * where prohibited.
+        * The fbt entry chain is in place, one entry point per symbol.
+        * The fbt return chain can have multiple return points per symbol.
+        * Here we find the end of the fbt return chain.
         */
-
-       if (LIT_STRNEQL(modname, "com.apple.driver.dtrace"))
+       
+       doenable=0;
+       
+       thisid = dtrace_probe_lookup(fbt_id, modname, symbolName, FBT_RETURN);
+       if (thisid != 0) {
+               /* The dtrace_probe previously existed, so we have to
+                * find the end of the existing fbt chain.  If we find
+                * an fbt return that was previously patched to fire,
+                * (as indicated by the currrent patched value), then
+                * we want to enable any new fbts on the spot.
+                */
+               retfbt = dtrace_probe_arg (fbt_id, thisid);
+               ASSERT(retfbt != NULL);
+               for (;  retfbt != NULL; retfbt =  retfbt->fbtp_next) {
+                       if (retfbt->fbtp_currentval == retfbt->fbtp_patchval)
+                               doenable++;
+                       if(retfbt->fbtp_next == NULL)
+                               break;
+               }
+       }
+       else {
+               doenable = 0;
+               retfbt = NULL;
+       }
+       
+again:
+       if (instr >= limit)
                return;
-
-       if (strstr(modname, "CHUD") != NULL)
+       
+       /*
+        * If this disassembly fails, then we've likely walked off into
+        * a jump table or some other unsuitable area.  Bail out of the
+        * disassembly now.
+        */
+       if ((size = dtrace_instr_size(instr)) <= 0)
                return;
-
-       if (mh->magic != MH_MAGIC)
+       
+       /*
+        * We (desperately) want to avoid erroneously instrumenting a
+        * jump table, especially given that our markers are pretty
+        * short:  two bytes on x86, and just one byte on amd64.  To
+        * determine if we're looking at a true instruction sequence
+        * or an inline jump table that happens to contain the same
+        * byte sequences, we resort to some heuristic sleeze:  we
+        * treat this instruction as being contained within a pointer,
+        * and see if that pointer points to within the body of the
+        * function.  If it does, we refuse to instrument it.
+        */
+       for (j = 0; j < sizeof (uintptr_t); j++) {
+               uintptr_t check = (uintptr_t)instr - j;
+               uint8_t *ptr;
+               
+               if (check < (uintptr_t)symbolStart)
+                       break;
+               
+               if (check + sizeof (uintptr_t) > (uintptr_t)limit)
+                       continue;
+               
+               ptr = *(uint8_t **)check;
+               
+               if (ptr >= (uint8_t *)symbolStart && ptr < limit) {
+                       instr += size;
+                       goto again;
+               }
+       }
+       
+       /*
+        * OK, it's an instruction.
+        */
+       theInstr = instr[0];
+       
+       /* Walked onto the start of the next routine? If so, bail out of this function. */
+       if (theInstr == FBT_PUSH_RBP)
+               return;
+       
+       if (!(size == 1 && (theInstr == FBT_POP_RBP || theInstr == FBT_LEAVE))) {
+               instr += size;
+               goto again;
+       }
+       
+       /*
+        * Found the pop %rbp; or leave.
+        */
+       machine_inst_t *patch_instr = instr;
+       
+       /*
+        * Scan forward for a "ret", or "jmp".
+        */
+       instr += size;
+       if (instr >= limit)
+               return;
+       
+       size = dtrace_instr_size(instr);
+       if (size <= 0) /* Failed instruction decode? */
+               return;
+       
+       theInstr = instr[0];
+       
+       if (!(size == FBT_RET_LEN && (theInstr == FBT_RET)) &&
+           !(size == FBT_RET_IMM16_LEN && (theInstr == FBT_RET_IMM16)) &&
+           !(size == FBT_JMP_SHORT_REL_LEN && (theInstr == FBT_JMP_SHORT_REL)) &&
+           !(size == FBT_JMP_NEAR_REL_LEN && (theInstr == FBT_JMP_NEAR_REL)) &&
+           !(size == FBT_JMP_FAR_ABS_LEN && (theInstr == FBT_JMP_FAR_ABS)))
                return;
+       
+       /*
+        * pop %rbp; ret; or leave; ret; or leave; jmp tailCalledFun; -- We have a winner!
+        */
+       newfbt = kmem_zalloc(sizeof (fbt_probe_t), KM_SLEEP);
+       strlcpy( (char *)&(newfbt->fbtp_name), symbolName, MAX_FBTP_NAME_CHARS );
+       
+       if (retfbt == NULL) {
+               newfbt->fbtp_id = dtrace_probe_create(fbt_id, modname,
+                                                     symbolName, FBT_RETURN, FBT_AFRAMES_RETURN, newfbt);
+       } else {
+               retfbt->fbtp_next = newfbt;
+               newfbt->fbtp_id = retfbt->fbtp_id;
+       }
+       
+       retfbt = newfbt;
+       newfbt->fbtp_patchpoint = patch_instr;
+       newfbt->fbtp_ctl = ctl;
+       newfbt->fbtp_loadcnt = ctl->mod_loadcnt;
+       
+       if (*patch_instr == FBT_POP_RBP) {
+               newfbt->fbtp_rval = DTRACE_INVOP_POP_RBP;
+       } else {
+               ASSERT(*patch_instr == FBT_LEAVE);
+               newfbt->fbtp_rval = DTRACE_INVOP_LEAVE;
+       }
+       newfbt->fbtp_roffset =
+       (uintptr_t)(patch_instr - (uint8_t *)symbolStart);
+       
+       newfbt->fbtp_savedval = *patch_instr;
+       newfbt->fbtp_patchval = FBT_PATCHVAL;
+       newfbt->fbtp_hashnext = fbt_probetab[FBT_ADDR2NDX(patch_instr)];
+       fbt_probetab[FBT_ADDR2NDX(patch_instr)] = newfbt;
+       
+       if (doenable)
+               fbt_enable(NULL, newfbt->fbtp_id, newfbt);
+       
+       instr += size;
+       goto again;
+}
 
+static void
+__kernel_syms_provide_module(void *arg, struct modctl *ctl)
+{
+#pragma unused(arg)
+       kernel_mach_header_t            *mh;
+       struct load_command             *cmd;
+       kernel_segment_command_t        *orig_ts = NULL, *orig_le = NULL;
+       struct symtab_command           *orig_st = NULL;
+       kernel_nlist_t                  *sym = NULL;
+       char                            *strings;
+       uintptr_t                       instrLow, instrHigh;
+       char                            *modname;
+       unsigned int                    i;
+       
+       mh = (kernel_mach_header_t *)(ctl->mod_address);
+       modname = ctl->mod_modname;
+       
+       if (mh->magic != MH_MAGIC_KERNEL)
+               return;
+       
        cmd = (struct load_command *) &mh[1];
        for (i = 0; i < mh->ncmds; i++) {
                if (cmd->cmd == LC_SEGMENT_KERNEL) {
                        kernel_segment_command_t *orig_sg = (kernel_segment_command_t *) cmd;
-
+                       
                        if (LIT_STRNEQL(orig_sg->segname, SEG_TEXT))
                                orig_ts = orig_sg;
                        else if (LIT_STRNEQL(orig_sg->segname, SEG_LINKEDIT))
@@ -468,950 +944,110 @@ __fbt_provide_module(void *arg, struct modctl *ctl)
                }
                else if (cmd->cmd == LC_SYMTAB)
                        orig_st = (struct symtab_command *) cmd;
-
+               
                cmd = (struct load_command *) ((caddr_t) cmd + cmd->cmdsize);
        }
-
+       
        if ((orig_ts == NULL) || (orig_st == NULL) || (orig_le == NULL))
                return;
-
-       sym = (struct nlist *)(orig_le->vmaddr + orig_st->symoff - orig_le->fileoff);
+       
+       sym = (kernel_nlist_t *)(orig_le->vmaddr + orig_st->symoff - orig_le->fileoff);
        strings = (char *)(orig_le->vmaddr + orig_st->stroff - orig_le->fileoff);
-
+       
        /* Find extent of the TEXT section */
        instrLow = (uintptr_t)orig_ts->vmaddr;
        instrHigh = (uintptr_t)(orig_ts->vmaddr + orig_ts->vmsize);
-
+       
        for (i = 0; i < orig_st->nsyms; i++) {
-               fbt_probe_t *fbt, *retfbt;
-               machine_inst_t *instr, *limit, theInstr, i1, i2;
                uint8_t n_type = sym[i].n_type & (N_TYPE | N_EXT);
                char *name = strings + sym[i].n_un.n_strx;
-               int size;
-
+               
                /* Check that the symbol is a global and that it has a name. */
                if (((N_SECT | N_EXT) != n_type && (N_ABS | N_EXT) != n_type))
                        continue;
-
+               
                if (0 == sym[i].n_un.n_strx) /* iff a null, "", name. */
                        continue;
                
                /* Lop off omnipresent leading underscore. */                   
                if (*name == '_')
                        name += 1;
-
-               if (LIT_STRNSTART(name, "dtrace_") && !LIT_STRNSTART(name, "dtrace_safe_")) {
-                       /*
-                        * Anything beginning with "dtrace_" may be called
-                        * from probe context unless it explitly indicates
-                        * that it won't be called from probe context by
-                        * using the prefix "dtrace_safe_".
-                        */
-                       continue;
-               }
-
-               if (LIT_STRNSTART(name, "dsmos_")) 
-                       continue; /* Don't Steal Mac OS X! */
-
-        if (LIT_STRNSTART(name, "_dtrace"))
-                       continue; /* Shims in dtrace.c */
-
-               if (LIT_STRNSTART(name, "chud"))
-                       continue; /* Professional courtesy. */
-               
-               if (LIT_STRNSTART(name, "hibernate_"))
-                       continue; /* Let sleeping dogs lie. */
                
-               if (LIT_STRNEQL(name, "_ZN9IOService14newTemperatureElPS_") || /* IOService::newTemperature */
-                       LIT_STRNEQL(name, "_ZN9IOService26temperatureCriticalForZoneEPS_")) /* IOService::temperatureCriticalForZone */
-                       continue; /* Per the fire code */
-
-               /*
-                * Place no probes (illegal instructions) in the exception handling path!
-                */
-               if (LIT_STRNEQL(name, "t_invop") ||
-                       LIT_STRNEQL(name, "enter_lohandler") ||
-                       LIT_STRNEQL(name, "lo_alltraps") ||
-                       LIT_STRNEQL(name, "kernel_trap") ||
-                       LIT_STRNEQL(name, "interrupt") ||                 
-                       LIT_STRNEQL(name, "i386_astintr"))
-                       continue;
-
-               if (LIT_STRNEQL(name, "current_thread") ||
-                       LIT_STRNEQL(name, "ast_pending") ||
-                       LIT_STRNEQL(name, "fbt_perfCallback") ||
-                       LIT_STRNEQL(name, "machine_thread_get_kern_state") ||
-                       LIT_STRNEQL(name, "get_threadtask") ||
-                       LIT_STRNEQL(name, "ml_set_interrupts_enabled") ||
-                       LIT_STRNEQL(name, "dtrace_invop") ||
-                       LIT_STRNEQL(name, "fbt_invop") ||
-                       LIT_STRNEQL(name, "sdt_invop") ||
-                       LIT_STRNEQL(name, "max_valid_stack_address"))
-                       continue;
-
-               /*
-                * Voodoo.
-                */
-               if (LIT_STRNSTART(name, "machine_stack_") ||
-                       LIT_STRNSTART(name, "mapping_") ||
-                       LIT_STRNEQL(name, "tmrCvt") ||
-
-                       LIT_STRNSTART(name, "tsc_") ||
-
-                       LIT_STRNSTART(name, "pmCPU") ||
-                       LIT_STRNEQL(name, "pmKextRegister") ||
-                       LIT_STRNEQL(name, "pmMarkAllCPUsOff") ||
-                       LIT_STRNEQL(name, "pmSafeMode") ||
-                       LIT_STRNEQL(name, "pmTimerSave") ||
-                       LIT_STRNEQL(name, "pmTimerRestore") ||
-                       LIT_STRNEQL(name, "pmUnRegister") ||
-                       LIT_STRNSTART(name, "pms") ||
-                       LIT_STRNEQL(name, "power_management_init") ||
-                       LIT_STRNSTART(name, "usimple_") ||
-                       LIT_STRNEQL(name, "lck_spin_lock") ||
-                       LIT_STRNEQL(name, "lck_spin_unlock") ||           
-
-                       LIT_STRNSTART(name, "rtc_") ||
-                       LIT_STRNSTART(name, "_rtc_") ||
-                       LIT_STRNSTART(name, "rtclock_") ||
-                       LIT_STRNSTART(name, "clock_") ||
-                       LIT_STRNSTART(name, "absolutetime_to_") ||
-                       LIT_STRNEQL(name, "setPop") ||
-                       LIT_STRNEQL(name, "nanoseconds_to_absolutetime") ||
-                       LIT_STRNEQL(name, "nanotime_to_absolutetime") ||
-
-                       LIT_STRNSTART(name, "etimer_") ||
-
-                       LIT_STRNSTART(name, "commpage_") ||
-                       LIT_STRNSTART(name, "pmap_") ||
-                       LIT_STRNSTART(name, "ml_") ||
-                       LIT_STRNSTART(name, "PE_") ||
-                       LIT_STRNEQL(name, "kprintf") ||
-                       LIT_STRNSTART(name, "lapic_") ||
-                       LIT_STRNSTART(name, "acpi_"))
-                       continue;
-
-        /*
-         * Avoid machine_ routines. PR_5346750.
-         */
-        if (LIT_STRNSTART(name, "machine_"))
-            continue;
-
-               if (LIT_STRNEQL(name, "handle_pending_TLB_flushes"))
-                       continue;
-
-        /*
-         * Place no probes on critical routines. PR_5221096
-         */
-        if (!gIgnoreFBTBlacklist &&
-            bsearch( name, critical_blacklist, CRITICAL_BLACKLIST_COUNT, sizeof(name), _cmp ) != NULL)
-                continue;
-
-        /*
-                * Place no probes that could be hit in probe context.
-                */
-               if (!gIgnoreFBTBlacklist && 
-                       bsearch( name, probe_ctx_closure, PROBE_CTX_CLOSURE_COUNT, sizeof(name), _cmp ) != NULL)
-                       continue;
-
                /*
-                * Place no probes that could be hit on the way to the debugger.
+                * We're only blacklisting functions in the kernel for now.
                 */
-               if (LIT_STRNSTART(name, "kdp_") ||
-                       LIT_STRNSTART(name, "kdb_") ||
-                       LIT_STRNSTART(name, "kdbg_") ||
-                       LIT_STRNSTART(name, "kdebug_") ||
-                       LIT_STRNEQL(name, "kernel_debug") ||
-                       LIT_STRNEQL(name, "Debugger") ||
-                       LIT_STRNEQL(name, "Call_DebuggerC") ||
-                       LIT_STRNEQL(name, "lock_debugger") ||
-                       LIT_STRNEQL(name, "unlock_debugger") ||
-                       LIT_STRNEQL(name, "SysChoked")) 
-                       continue;
-
-               /*
-                * Place no probes that could be hit on the way to a panic.
-                */
-               if (NULL != strstr(name, "panic_") ||
-                       LIT_STRNEQL(name, "panic") ||
-                       LIT_STRNEQL(name, "handleMck") ||
-                       LIT_STRNEQL(name, "unresolved_kernel_trap"))
+               if (MOD_IS_MACH_KERNEL(ctl) && !is_symbol_valid(name))
                        continue;
                
-               if (dtrace_probe_lookup(fbt_id, modname, name, NULL) != 0)
-                       continue;
-
-               for (j = 0, instr = (machine_inst_t *)sym[i].n_value, theInstr = 0;
-                        (j < 4) && ((uintptr_t)instr >= instrLow) && (instrHigh > (uintptr_t)(instr + 2)); 
-                        j++) {
-                       theInstr = instr[0];
-                       if (theInstr == FBT_PUSHL_EBP || theInstr == FBT_RET || theInstr == FBT_RET_IMM16)
-                               break;
-
-                       if ((size = dtrace_instr_size(instr)) <= 0)
-                               break;
-                       instr += size;
-               }
-
-               if (theInstr != FBT_PUSHL_EBP)
-                       continue;
-
-               i1 = instr[1];
-               i2 = instr[2];
-
-               limit = (machine_inst_t *)instrHigh;
-
-               if ((i1 == FBT_MOVL_ESP_EBP0_V0 && i2 == FBT_MOVL_ESP_EBP1_V0) ||
-                       (i1 == FBT_MOVL_ESP_EBP0_V1 && i2 == FBT_MOVL_ESP_EBP1_V1)) {
-                               instr += 1; /* Advance to the movl %esp,%ebp */
-                               theInstr = i1;
-               } else {
-                       /*
-                        * Sometimes, the compiler will schedule an intervening instruction
-                        * in the function prologue. Example:
-                        *
-                        * _mach_vm_read:
-                        * 000006d8        pushl   %ebp
-                        * 000006d9        movl    $0x00000004,%edx
-                        * 000006de        movl    %esp,%ebp
-                        * 
-                        * Try the next instruction, to see if it is a movl %esp,%ebp
-                        */
-
-                       instr += 1; /* Advance past the pushl %ebp */
-                       if ((size = dtrace_instr_size(instr)) <= 0)
-                               continue;
-                       instr += size;
-
-                       if ((instr + 1) >= limit)
-                               continue;
-
-                       i1 = instr[0];
-                       i2 = instr[1];
-
-                       if (!(i1 == FBT_MOVL_ESP_EBP0_V0 && i2 == FBT_MOVL_ESP_EBP1_V0) &&
-                               !(i1 == FBT_MOVL_ESP_EBP0_V1 && i2 == FBT_MOVL_ESP_EBP1_V1))
-                               continue;
-
-                       /* instr already points at the movl %esp,%ebp */
-                       theInstr = i1;
-               }
-
-               fbt = kmem_zalloc(sizeof (fbt_probe_t), KM_SLEEP);
-               strlcpy( (char *)&(fbt->fbtp_name), name, MAX_FBTP_NAME_CHARS );
-               fbt->fbtp_id = dtrace_probe_create(fbt_id, modname, name, FBT_ENTRY, FBT_AFRAMES_ENTRY, fbt);
-               fbt->fbtp_patchpoint = instr;
-               fbt->fbtp_ctl = ctl;
-               fbt->fbtp_loadcnt = ctl->mod_loadcnt;
-               fbt->fbtp_rval = DTRACE_INVOP_MOVL_ESP_EBP;
-               fbt->fbtp_savedval = theInstr;
-               fbt->fbtp_patchval = FBT_PATCHVAL;
-
-               fbt->fbtp_hashnext = fbt_probetab[FBT_ADDR2NDX(instr)];
-               fbt->fbtp_symndx = i;
-               fbt_probetab[FBT_ADDR2NDX(instr)] = fbt;
-
-               retfbt = NULL;
-again:
-               if (instr >= limit)
-                       continue;
-
-               /*
-                * If this disassembly fails, then we've likely walked off into
-                * a jump table or some other unsuitable area.  Bail out of the
-                * disassembly now.
-                */
-               if ((size = dtrace_instr_size(instr)) <= 0)
-                       continue;
-
-               /*
-                * We (desperately) want to avoid erroneously instrumenting a
-                * jump table, especially given that our markers are pretty
-                * short:  two bytes on x86, and just one byte on amd64.  To
-                * determine if we're looking at a true instruction sequence
-                * or an inline jump table that happens to contain the same
-                * byte sequences, we resort to some heuristic sleeze:  we
-                * treat this instruction as being contained within a pointer,
-                * and see if that pointer points to within the body of the
-                * function.  If it does, we refuse to instrument it.
-                */
-               for (j = 0; j < sizeof (uintptr_t); j++) {
-                       uintptr_t check = (uintptr_t)instr - j;
-                       uint8_t *ptr;
-
-                       if (check < sym[i].n_value)
-                               break;
-
-                       if (check + sizeof (uintptr_t) > (uintptr_t)limit)
-                               continue;
-
-                       ptr = *(uint8_t **)check;
-
-                       if (ptr >= (uint8_t *)sym[i].n_value && ptr < limit) {
-                               instr += size;
-                               goto again;
-                       }
-               }
-
-               /*
-                * OK, it's an instruction.
-                */
-               theInstr = instr[0];
-
-               /* Walked onto the start of the next routine? If so, bail out of this function. */
-               if (theInstr == FBT_PUSHL_EBP)
-                       continue;
-
-               if (!(size == 1 && (theInstr == FBT_POPL_EBP || theInstr == FBT_LEAVE))) {
-                       instr += size;
-                       goto again;
-               }
-
-               /*
-                * Found the popl %ebp; or leave.
-                */
-               machine_inst_t *patch_instr = instr;
-
-               /*
-                * Scan forward for a "ret", or "jmp".
-                */
-               instr += size;
-               if (instr >= limit)
-                       continue;
-
-               size = dtrace_instr_size(instr);
-               if (size <= 0) /* Failed instruction decode? */
-                       continue;
-
-               theInstr = instr[0];
-
-               if (!(size == FBT_RET_LEN && (theInstr == FBT_RET)) &&
-                       !(size == FBT_RET_IMM16_LEN && (theInstr == FBT_RET_IMM16)) &&
-                       !(size == FBT_JMP_SHORT_REL_LEN && (theInstr == FBT_JMP_SHORT_REL)) &&
-                       !(size == FBT_JMP_NEAR_REL_LEN && (theInstr == FBT_JMP_NEAR_REL)) &&
-                       !(size == FBT_JMP_FAR_ABS_LEN && (theInstr == FBT_JMP_FAR_ABS)))
-                       continue;
-
-               /*
-                * popl %ebp; ret; or leave; ret; or leave; jmp tailCalledFun; -- We have a winner!
-                */
-               fbt = kmem_zalloc(sizeof (fbt_probe_t), KM_SLEEP);
-               strlcpy( (char *)&(fbt->fbtp_name), name, MAX_FBTP_NAME_CHARS );
-
-               if (retfbt == NULL) {
-                       fbt->fbtp_id = dtrace_probe_create(fbt_id, modname,
-                           name, FBT_RETURN, FBT_AFRAMES_RETURN, fbt);
-               } else {
-                       retfbt->fbtp_next = fbt;
-                       fbt->fbtp_id = retfbt->fbtp_id;
-               }
-
-               retfbt = fbt;
-               fbt->fbtp_patchpoint = patch_instr;
-               fbt->fbtp_ctl = ctl;
-               fbt->fbtp_loadcnt = ctl->mod_loadcnt;
-
-               if (*patch_instr == FBT_POPL_EBP) {
-                       fbt->fbtp_rval = DTRACE_INVOP_POPL_EBP;
-               } else {
-                       ASSERT(*patch_instr == FBT_LEAVE);
-                       fbt->fbtp_rval = DTRACE_INVOP_LEAVE;
-               }
-               fbt->fbtp_roffset =
-                   (uintptr_t)(patch_instr - (uint8_t *)sym[i].n_value);
-
-               fbt->fbtp_savedval = *patch_instr;
-               fbt->fbtp_patchval = FBT_PATCHVAL;
-               fbt->fbtp_hashnext = fbt_probetab[FBT_ADDR2NDX(patch_instr)];
-               fbt->fbtp_symndx = i;
-               fbt_probetab[FBT_ADDR2NDX(patch_instr)] = fbt;
-
-               instr += size;
-               goto again;
-       }
-}
-#elif defined(__x86_64__)
-int
-fbt_invop(uintptr_t addr, uintptr_t *state, uintptr_t rval)
-{
-       fbt_probe_t *fbt = fbt_probetab[FBT_ADDR2NDX(addr)];
-       
-       for (; fbt != NULL; fbt = fbt->fbtp_hashnext) {
-               if ((uintptr_t)fbt->fbtp_patchpoint == addr) {
-
-                       if (fbt->fbtp_roffset == 0) {
-                               x86_saved_state64_t *regs = (x86_saved_state64_t *)state;
-
-                               CPU->cpu_dtrace_caller = *(uintptr_t *)(((uintptr_t)(regs->isf.rsp))+sizeof(uint64_t)); // 8(%rsp)
-                               /* 64-bit ABI, arguments passed in registers. */
-                               dtrace_probe(fbt->fbtp_id, regs->rdi, regs->rsi, regs->rdx, regs->rcx, regs->r8);
-                               CPU->cpu_dtrace_caller = 0;
-                       } else {
-
-                               dtrace_probe(fbt->fbtp_id, fbt->fbtp_roffset, rval, 0, 0, 0);
-                               CPU->cpu_dtrace_caller = 0;
-                       }
-
-                       return (fbt->fbtp_rval);
-               }
-       }
-
-       return (0);
-}
-
-#define IS_USER_TRAP(regs) (regs && (((regs)->isf.cs & 3) != 0))
-#define T_INVALID_OPCODE 6
-#define FBT_EXCEPTION_CODE T_INVALID_OPCODE
-#define T_PREEMPT       255
-
-kern_return_t
-fbt_perfCallback(
-                int                    trapno,
-                x86_saved_state_t      *tagged_regs,
-                __unused int        unused1,
-                __unused int        unused2)
-{
-       kern_return_t retval = KERN_FAILURE;
-       x86_saved_state64_t *saved_state = saved_state64(tagged_regs);
-
-       if (FBT_EXCEPTION_CODE == trapno && !IS_USER_TRAP(saved_state)) {
-               boolean_t oldlevel;
-               uint64_t rsp_probe, *rbp, r12, fp, delta = 0;
-               uint32_t *pDst;
-               int emul;
-
-               oldlevel = ml_set_interrupts_enabled(FALSE);
-
-               /* Calculate where the stack pointer was when the probe instruction "fired." */
-               rsp_probe = saved_state->isf.rsp; /* Easy, x86_64 establishes this value in idt64.s */
-
-               emul = dtrace_invop( saved_state->isf.rip, (uintptr_t *)saved_state, saved_state->rax );
-               __asm__ volatile(".globl _dtrace_invop_callsite");
-               __asm__ volatile("_dtrace_invop_callsite:");
-
-               switch (emul) {
-               case DTRACE_INVOP_NOP:
-                       saved_state->isf.rip += DTRACE_INVOP_NOP_SKIP;  /* Skip over the patched NOP (planted by sdt). */
-                       retval = KERN_SUCCESS;
-                       break;
-
-               case DTRACE_INVOP_MOV_RSP_RBP:
-                       saved_state->rbp = rsp_probe;                                                   /* Emulate patched mov %rsp,%rbp */
-                       saved_state->isf.rip += DTRACE_INVOP_MOV_RSP_RBP_SKIP;  /* Skip over the bytes of the patched mov %rsp,%rbp */
-                       retval = KERN_SUCCESS;
-                       break;
-
-               case DTRACE_INVOP_POP_RBP:
-               case DTRACE_INVOP_LEAVE:
-/*
- * Emulate first micro-op of patched leave: mov %rbp,%rsp
- * fp points just below the return address slot for target's ret 
- * and at the slot holding the frame pointer saved by the target's prologue.
- */
-                       fp = saved_state->rbp;
-/* Emulate second micro-op of patched leave: patched pop %rbp
- * savearea rbp is set for the frame of the caller to target
- * The *live* %rsp will be adjusted below for pop increment(s)
- */
-                       saved_state->rbp = *(uint64_t *)fp;
-/* Skip over the patched leave */
-                       saved_state->isf.rip += DTRACE_INVOP_LEAVE_SKIP;
-/*
- * Lift the stack to account for the emulated leave
- * Account for words local in this frame
- * (in "case DTRACE_INVOP_POPL_EBP:" this is zero.)
- */
-                       delta = ((uint32_t *)fp) - ((uint32_t *)rsp_probe); /* delta is a *word* increment */
-/* Account for popping off the rbp (just accomplished by the emulation
- * above...)
- */
-                       delta += 2;
-                       saved_state->isf.rsp += (delta << 2);
-
-/* XXX Fragile in the extreme. 
- * This is sensitive to trap_from_kernel()'s internals.
- */
-                       rbp = (uint64_t *)__builtin_frame_address(0);
-                       rbp = (uint64_t *)*rbp;
-                       r12 = *(rbp - 4);
-
-/* Shift contents of stack */
-                       for (pDst = (uint32_t *)fp;
-                            pDst > (((uint32_t *)r12));
-                                pDst--)
-                               *pDst = pDst[-delta];
-
-/* Track the stack lift in "saved_state". */
-                       saved_state = (x86_saved_state64_t *) (((uintptr_t)saved_state) + (delta << 2));
-
-/* Now adjust the value of %r12 in our caller (kernel_trap)'s frame */
-                       *(rbp - 4) = r12 + (delta << 2);
-
-                       retval = KERN_SUCCESS;
-                       break;
-                       
-               default:
-                       retval = KERN_FAILURE;
-                       break;
-               }
-               saved_state->isf.trapno = T_PREEMPT; /* Avoid call to i386_astintr()! */
-
-               ml_set_interrupts_enabled(oldlevel);
+               __provide_probe_64(ctl, instrLow, instrHigh, modname, name, (machine_inst_t*)sym[i].n_value);
        }
-
-       return retval;
 }
 
-/*ARGSUSED*/
 static void
-__fbt_provide_module(void *arg, struct modctl *ctl)
+__user_syms_provide_module(void *arg, struct modctl *ctl)
 {
 #pragma unused(arg)
-       kernel_mach_header_t            *mh;
-       struct load_command         *cmd;
-       kernel_segment_command_t        *orig_ts = NULL, *orig_le = NULL;
-       struct symtab_command       *orig_st = NULL;
-       struct nlist_64             *sym = NULL;
-       char                                            *strings;
-       uintptr_t                                       instrLow, instrHigh;
-       char                                            *modname;
-       unsigned int                            i, j;
-
-       int gIgnoreFBTBlacklist = 0;
-       PE_parse_boot_argn("IgnoreFBTBlacklist", &gIgnoreFBTBlacklist, sizeof (gIgnoreFBTBlacklist));
-
-       mh = (kernel_mach_header_t *)(ctl->address);
+       char                            *modname;
+       unsigned int                    i;
+       
        modname = ctl->mod_modname;
+       
+       dtrace_module_symbols_t* module_symbols = ctl->mod_user_symbols;
+       if (module_symbols) {
+               for (i=0; i<module_symbols->dtmodsyms_count; i++) {
 
-       if (0 == ctl->address || 0 == ctl->size) /* Has the linker been jettisoned? */
-               return;
-
-       /*
-        * Employees of dtrace and their families are ineligible.  Void
-        * where prohibited.
-        */
-
-       if (LIT_STRNEQL(modname, "com.apple.driver.dtrace"))
-               return;
-
-       if (strstr(modname, "CHUD") != NULL)
-               return;
-
-       if (mh->magic != MH_MAGIC_64)
-               return;
-
-       cmd = (struct load_command *) &mh[1];
-       for (i = 0; i < mh->ncmds; i++) {
-               if (cmd->cmd == LC_SEGMENT_KERNEL) {
-                       kernel_segment_command_t *orig_sg = (kernel_segment_command_t *) cmd;
-
-                       if (LIT_STRNEQL(orig_sg->segname, SEG_TEXT))
-                               orig_ts = orig_sg;
-                       else if (LIT_STRNEQL(orig_sg->segname, SEG_LINKEDIT))
-                               orig_le = orig_sg;
-                       else if (LIT_STRNEQL(orig_sg->segname, ""))
-                               orig_ts = orig_sg; /* kexts have a single unnamed segment */
-               }
-               else if (cmd->cmd == LC_SYMTAB)
-                       orig_st = (struct symtab_command *) cmd;
-
-               cmd = (struct load_command *) ((caddr_t) cmd + cmd->cmdsize);
-       }
-
-       if ((orig_ts == NULL) || (orig_st == NULL) || (orig_le == NULL))
-               return;
-
-       sym = (struct nlist_64 *)(orig_le->vmaddr + orig_st->symoff - orig_le->fileoff);
-       strings = (char *)(orig_le->vmaddr + orig_st->stroff - orig_le->fileoff);
-
-       /* Find extent of the TEXT section */
-       instrLow = (uintptr_t)orig_ts->vmaddr;
-       instrHigh = (uintptr_t)(orig_ts->vmaddr + orig_ts->vmsize);
-
-       for (i = 0; i < orig_st->nsyms; i++) {
-               fbt_probe_t *fbt, *retfbt;
-               machine_inst_t *instr, *limit, theInstr, i1, i2, i3;
-               uint8_t n_type = sym[i].n_type & (N_TYPE | N_EXT);
-               char *name = strings + sym[i].n_un.n_strx;
-               int size;
-
-               /* Check that the symbol is a global and that it has a name. */
-               if (((N_SECT | N_EXT) != n_type && (N_ABS | N_EXT) != n_type))
-                       continue;
-
-               if (0 == sym[i].n_un.n_strx) /* iff a null, "", name. */
-                       continue;
-               
-               /* Lop off omnipresent leading underscore. */                   
-               if (*name == '_')
-                       name += 1;
-
-               if (LIT_STRNSTART(name, "dtrace_") && !LIT_STRNSTART(name, "dtrace_safe_")) {
-                       /*
-                        * Anything beginning with "dtrace_" may be called
-                        * from probe context unless it explitly indicates
-                        * that it won't be called from probe context by
-                        * using the prefix "dtrace_safe_".
+                       /* 
+                        * symbol->dtsym_addr (the symbol address) passed in from
+                        * user space, is already slid for both kexts and kernel.
                         */
-                       continue;
-               }
-
-               if (LIT_STRNSTART(name, "fasttrap_") ||
-                   LIT_STRNSTART(name, "fuword") ||
-                   LIT_STRNSTART(name, "suword") ||
-                       LIT_STRNEQL(name, "sprlock") ||
-                       LIT_STRNEQL(name, "sprunlock") ||
-                       LIT_STRNEQL(name, "uread") ||
-                       LIT_STRNEQL(name, "uwrite"))
-                       continue; /* Fasttrap inner-workings. */
-
-               if (LIT_STRNSTART(name, "dsmos_")) 
-                       continue; /* Don't Steal Mac OS X! */
-
-        if (LIT_STRNSTART(name, "_dtrace"))
-                       continue; /* Shims in dtrace.c */
-
-               if (LIT_STRNSTART(name, "chud"))
-                       continue; /* Professional courtesy. */
-               
-               if (LIT_STRNSTART(name, "hibernate_"))
-                       continue; /* Let sleeping dogs lie. */
-               
-               if (LIT_STRNEQL(name, "ZN9IOService14newTemperatureElPS_") || /* IOService::newTemperature */
-                       LIT_STRNEQL(name, "ZN9IOService26temperatureCriticalForZoneEPS_")) /* IOService::temperatureCriticalForZone */
-                       continue; /* Per the fire code */
-
-               /*
-                * Place no probes (illegal instructions) in the exception handling path!
-                */
-               if (LIT_STRNEQL(name, "t_invop") ||
-                       LIT_STRNEQL(name, "enter_lohandler") ||
-                       LIT_STRNEQL(name, "lo_alltraps") ||
-                       LIT_STRNEQL(name, "kernel_trap") ||
-                       LIT_STRNEQL(name, "interrupt") ||                 
-                       LIT_STRNEQL(name, "i386_astintr"))
-                       continue;
-
-               if (LIT_STRNEQL(name, "current_thread") ||
-                       LIT_STRNEQL(name, "ast_pending") ||
-                       LIT_STRNEQL(name, "fbt_perfCallback") ||
-                       LIT_STRNEQL(name, "machine_thread_get_kern_state") ||
-                       LIT_STRNEQL(name, "get_threadtask") ||
-                       LIT_STRNEQL(name, "ml_set_interrupts_enabled") ||
-                       LIT_STRNEQL(name, "dtrace_invop") ||
-                       LIT_STRNEQL(name, "fbt_invop") ||
-                       LIT_STRNEQL(name, "sdt_invop") ||
-                       LIT_STRNEQL(name, "max_valid_stack_address"))
-                       continue;
-
-               /*
-                * Voodoo.
-                */
-               if (LIT_STRNSTART(name, "machine_stack_") ||
-                       LIT_STRNSTART(name, "mapping_") ||
-                       LIT_STRNEQL(name, "tmrCvt") ||
-
-                       LIT_STRNSTART(name, "tsc_") ||
-
-                       LIT_STRNSTART(name, "pmCPU") ||
-                       LIT_STRNEQL(name, "pmKextRegister") ||
-                       LIT_STRNEQL(name, "pmMarkAllCPUsOff") || 
-                       LIT_STRNEQL(name, "pmSafeMode") ||
-                       LIT_STRNEQL(name, "pmTimerSave") ||
-                       LIT_STRNEQL(name, "pmTimerRestore") ||            
-                       LIT_STRNEQL(name, "pmUnRegister") ||
-                       LIT_STRNSTART(name, "pms") ||
-                       LIT_STRNEQL(name, "power_management_init") ||
-                       LIT_STRNSTART(name, "usimple_") ||
-                       LIT_STRNSTART(name, "lck_spin_lock") ||
-                       LIT_STRNSTART(name, "lck_spin_unlock") ||
-
-                       LIT_STRNSTART(name, "rtc_") ||
-                       LIT_STRNSTART(name, "_rtc_") ||
-                       LIT_STRNSTART(name, "rtclock_") ||
-                       LIT_STRNSTART(name, "clock_") ||
-                       LIT_STRNSTART(name, "absolutetime_to_") ||
-                       LIT_STRNEQL(name, "setPop") ||
-                       LIT_STRNEQL(name, "nanoseconds_to_absolutetime") ||
-                       LIT_STRNEQL(name, "nanotime_to_absolutetime") ||
-
-                       LIT_STRNSTART(name, "etimer_") ||
-
-                       LIT_STRNSTART(name, "commpage_") ||
-                       LIT_STRNSTART(name, "pmap_") ||
-                       LIT_STRNSTART(name, "ml_") ||
-                       LIT_STRNSTART(name, "PE_") ||
-                       LIT_STRNEQL(name, "kprintf") ||
-                       LIT_STRNSTART(name, "lapic_") ||
-                       LIT_STRNSTART(name, "acpi_"))
-                       continue;
-
-        /*
-         * Avoid machine_ routines. PR_5346750.
-         */
-        if (LIT_STRNSTART(name, "machine_"))
-            continue;
-
-               if (LIT_STRNEQL(name, "handle_pending_TLB_flushes"))
-                       continue;
+                       dtrace_symbol_t* symbol = &module_symbols->dtmodsyms_symbols[i];
 
-        /*
-         * Place no probes on critical routines. PR_5221096
-         */
-        if (!gIgnoreFBTBlacklist &&
-            bsearch( name, critical_blacklist, CRITICAL_BLACKLIST_COUNT, sizeof(name), _cmp ) != NULL)
-                continue;
-
-        /*
-                * Place no probes that could be hit in probe context.
-                */
-               if (!gIgnoreFBTBlacklist && 
-                       bsearch( name, probe_ctx_closure, PROBE_CTX_CLOSURE_COUNT, sizeof(name), _cmp ) != NULL)
-                       continue;
-
-               /*
-                * Place no probes that could be hit on the way to the debugger.
-                */
-               if (LIT_STRNSTART(name, "kdp_") ||
-                       LIT_STRNSTART(name, "kdb_") ||
-                       LIT_STRNSTART(name, "kdbg_") ||
-                       LIT_STRNSTART(name, "kdebug_") ||
-                       LIT_STRNEQL(name, "kernel_debug") ||
-                       LIT_STRNEQL(name, "Debugger") ||
-                       LIT_STRNEQL(name, "Call_DebuggerC") ||
-                       LIT_STRNEQL(name, "lock_debugger") ||
-                       LIT_STRNEQL(name, "unlock_debugger") ||
-                       LIT_STRNEQL(name, "SysChoked")) 
-                       continue;
-
-               /*
-                * Place no probes that could be hit on the way to a panic.
-                */
-               if (NULL != strstr(name, "panic_") ||
-                       LIT_STRNEQL(name, "panic") ||
-                       LIT_STRNEQL(name, "handleMck") ||
-                       LIT_STRNEQL(name, "unresolved_kernel_trap"))
-                       continue;
-               
-               if (dtrace_probe_lookup(fbt_id, modname, name, NULL) != 0)
-                       continue;
-
-               for (j = 0, instr = (machine_inst_t *)sym[i].n_value, theInstr = 0;
-                        (j < 4) && ((uintptr_t)instr >= instrLow) && (instrHigh > (uintptr_t)(instr + 2)); 
-                        j++) {
-                       theInstr = instr[0];
-                       if (theInstr == FBT_PUSH_RBP || theInstr == FBT_RET || theInstr == FBT_RET_IMM16)
-                               break;
-
-                       if ((size = dtrace_instr_size(instr)) <= 0)
-                               break;
-                       instr += size;
-               }
-
-               if (theInstr != FBT_PUSH_RBP)
-                       continue;
-
-               i1 = instr[1];
-               i2 = instr[2];
-               i3 = instr[3];
-
-               limit = (machine_inst_t *)instrHigh;
-
-               if (i1 == FBT_REX_RSP_RBP && i2 == FBT_MOV_RSP_RBP0 && i3 == FBT_MOV_RSP_RBP1) {
-                               instr += 1; /* Advance to the mov %rsp,%rbp */
-                               theInstr = i1;
-               } else {
-                       continue;
-               }
-#if 0
-               else {
+                       char* name = symbol->dtsym_name;
+                       
+                       /* Lop off omnipresent leading underscore. */                   
+                       if (*name == '_')
+                               name += 1;
+                       
                        /*
-                        * Sometimes, the compiler will schedule an intervening instruction
-                        * in the function prologue. Example:
-                        *
-                        * _mach_vm_read:
-                        * 000006d8        pushl   %ebp
-                        * 000006d9        movl    $0x00000004,%edx
-                        * 000006de        movl    %esp,%ebp
-                        * 
-                        * Try the next instruction, to see if it is a movl %esp,%ebp
+                        * We're only blacklisting functions in the kernel for now.
                         */
-
-                       instr += 1; /* Advance past the pushl %ebp */
-                       if ((size = dtrace_instr_size(instr)) <= 0)
-                               continue;
-                       instr += size;
-
-                       if ((instr + 1) >= limit)
-                               continue;
-
-                       i1 = instr[0];
-                       i2 = instr[1];
-
-                       if (!(i1 == FBT_MOVL_ESP_EBP0_V0 && i2 == FBT_MOVL_ESP_EBP1_V0) &&
-                               !(i1 == FBT_MOVL_ESP_EBP0_V1 && i2 == FBT_MOVL_ESP_EBP1_V1))
-                               continue;
-
-                       /* instr already points at the movl %esp,%ebp */
-                       theInstr = i1;
-               }
-#endif
-
-               fbt = kmem_zalloc(sizeof (fbt_probe_t), KM_SLEEP);
-               strlcpy( (char *)&(fbt->fbtp_name), name, MAX_FBTP_NAME_CHARS );
-               fbt->fbtp_id = dtrace_probe_create(fbt_id, modname, name, FBT_ENTRY, FBT_AFRAMES_ENTRY, fbt);
-               fbt->fbtp_patchpoint = instr;
-               fbt->fbtp_ctl = ctl;
-               fbt->fbtp_loadcnt = ctl->mod_loadcnt;
-               fbt->fbtp_rval = DTRACE_INVOP_MOV_RSP_RBP;
-               fbt->fbtp_savedval = theInstr;
-               fbt->fbtp_patchval = FBT_PATCHVAL;
-
-               fbt->fbtp_hashnext = fbt_probetab[FBT_ADDR2NDX(instr)];
-               fbt->fbtp_symndx = i;
-               fbt_probetab[FBT_ADDR2NDX(instr)] = fbt;
-
-               retfbt = NULL;
-again:
-               if (instr >= limit)
-                       continue;
-
-               /*
-                * If this disassembly fails, then we've likely walked off into
-                * a jump table or some other unsuitable area.  Bail out of the
-                * disassembly now.
-                */
-               if ((size = dtrace_instr_size(instr)) <= 0)
-                       continue;
-
-               /*
-                * We (desperately) want to avoid erroneously instrumenting a
-                * jump table, especially given that our markers are pretty
-                * short:  two bytes on x86, and just one byte on amd64.  To
-                * determine if we're looking at a true instruction sequence
-                * or an inline jump table that happens to contain the same
-                * byte sequences, we resort to some heuristic sleeze:  we
-                * treat this instruction as being contained within a pointer,
-                * and see if that pointer points to within the body of the
-                * function.  If it does, we refuse to instrument it.
-                */
-               for (j = 0; j < sizeof (uintptr_t); j++) {
-                       uintptr_t check = (uintptr_t)instr - j;
-                       uint8_t *ptr;
-
-                       if (check < sym[i].n_value)
-                               break;
-
-                       if (check + sizeof (uintptr_t) > (uintptr_t)limit)
-                               continue;
-
-                       ptr = *(uint8_t **)check;
-
-                       if (ptr >= (uint8_t *)sym[i].n_value && ptr < limit) {
-                               instr += size;
-                               goto again;
-                       }
-               }
-
-               /*
-                * OK, it's an instruction.
-                */
-               theInstr = instr[0];
-
-               /* Walked onto the start of the next routine? If so, bail out of this function. */
-               if (theInstr == FBT_PUSH_RBP)
-                       continue;
-
-               if (!(size == 1 && (theInstr == FBT_POP_RBP || theInstr == FBT_LEAVE))) {
-                       instr += size;
-                       goto again;
-               }
-
-               /*
-                * Found the pop %rbp; or leave.
-                */
-               machine_inst_t *patch_instr = instr;
-
-               /*
-                * Scan forward for a "ret", or "jmp".
-                */
-               instr += size;
-               if (instr >= limit)
-                       continue;
-
-               size = dtrace_instr_size(instr);
-               if (size <= 0) /* Failed instruction decode? */
-                       continue;
-
-               theInstr = instr[0];
-
-               if (!(size == FBT_RET_LEN && (theInstr == FBT_RET)) &&
-                       !(size == FBT_RET_IMM16_LEN && (theInstr == FBT_RET_IMM16)) &&
-                       !(size == FBT_JMP_SHORT_REL_LEN && (theInstr == FBT_JMP_SHORT_REL)) &&
-                       !(size == FBT_JMP_NEAR_REL_LEN && (theInstr == FBT_JMP_NEAR_REL)) &&
-                       !(size == FBT_JMP_FAR_ABS_LEN && (theInstr == FBT_JMP_FAR_ABS)))
-                       continue;
-
-               /*
-                * pop %rbp; ret; or leave; ret; or leave; jmp tailCalledFun; -- We have a winner!
-                */
-               fbt = kmem_zalloc(sizeof (fbt_probe_t), KM_SLEEP);
-               strlcpy( (char *)&(fbt->fbtp_name), name, MAX_FBTP_NAME_CHARS );
-
-               if (retfbt == NULL) {
-                       fbt->fbtp_id = dtrace_probe_create(fbt_id, modname,
-                           name, FBT_RETURN, FBT_AFRAMES_RETURN, fbt);
-               } else {
-                       retfbt->fbtp_next = fbt;
-                       fbt->fbtp_id = retfbt->fbtp_id;
-               }
-
-               retfbt = fbt;
-               fbt->fbtp_patchpoint = patch_instr;
-               fbt->fbtp_ctl = ctl;
-               fbt->fbtp_loadcnt = ctl->mod_loadcnt;
-
-               if (*patch_instr == FBT_POP_RBP) {
-                       fbt->fbtp_rval = DTRACE_INVOP_POP_RBP;
-               } else {
-                       ASSERT(*patch_instr == FBT_LEAVE);
-                       fbt->fbtp_rval = DTRACE_INVOP_LEAVE;
+                        if (MOD_IS_MACH_KERNEL(ctl) && !is_symbol_valid(name))
+                               continue;
+                       
+                       __provide_probe_64(ctl, (uintptr_t)symbol->dtsym_addr, (uintptr_t)(symbol->dtsym_addr + symbol->dtsym_size), modname, name, (machine_inst_t*)(uintptr_t)symbol->dtsym_addr);
                }
-               fbt->fbtp_roffset =
-                   (uintptr_t)(patch_instr - (uint8_t *)sym[i].n_value);
-
-               fbt->fbtp_savedval = *patch_instr;
-               fbt->fbtp_patchval = FBT_PATCHVAL;
-               fbt->fbtp_hashnext = fbt_probetab[FBT_ADDR2NDX(patch_instr)];
-               fbt->fbtp_symndx = i;
-               fbt_probetab[FBT_ADDR2NDX(patch_instr)] = fbt;
-
-               instr += size;
-               goto again;
        }
 }
-#else
-#error Unknown arch
-#endif
 
-extern struct modctl g_fbt_kernctl;
-#undef kmem_alloc /* from its binding to dt_kmem_alloc glue */
-#undef kmem_free /* from its binding to dt_kmem_free glue */
-#include <vm/vm_kern.h>
+extern int dtrace_kernel_symbol_mode;
 
 /*ARGSUSED*/
 void
 fbt_provide_module(void *arg, struct modctl *ctl)
 {
-#pragma unused(ctl)
-       __fbt_provide_module(arg, &g_fbt_kernctl);
+       ASSERT(ctl != NULL);
+       ASSERT(dtrace_kernel_symbol_mode != DTRACE_KERNEL_SYMBOLS_NEVER);
+       lck_mtx_assert(&mod_lock, LCK_MTX_ASSERT_OWNED);
 
-       if ( (vm_offset_t)g_fbt_kernctl.address != (vm_offset_t )NULL )
-           kmem_free(kernel_map, (vm_offset_t)g_fbt_kernctl.address, round_page(g_fbt_kernctl.size));
-       g_fbt_kernctl.address = 0;
-       g_fbt_kernctl.size = 0;
+       if (MOD_FBT_DONE(ctl))
+               return;
+       
+       if (!is_module_valid(ctl)) {
+               ctl->mod_flags |= MODCTL_FBT_INVALID;
+               return;
+       }
+       
+       if (MOD_HAS_KERNEL_SYMBOLS(ctl)) {
+               __kernel_syms_provide_module(arg, ctl);
+               ctl->mod_flags |= MODCTL_FBT_PROBES_PROVIDED;
+               return;
+       }
+       
+       if (MOD_HAS_USERSPACE_SYMBOLS(ctl)) {
+               __user_syms_provide_module(arg, ctl);
+               ctl->mod_flags |= MODCTL_FBT_PROBES_PROVIDED;
+               if (MOD_FBT_PROVIDE_PRIVATE_PROBES(ctl))
+                       ctl->mod_flags |= MODCTL_FBT_PRIVATE_PROBES_PROVIDED;
+               return;
+       }       
 }