#include <mach_kdp.h>
#include <mach_ldebug.h>
#include <types.h>
#include <i386/eflags.h>
#include <i386/trap.h>
#include <i386/pmap.h>
#include <i386/fpu.h>
#include <i386/misc_protos.h>
#include <i386/lapic.h>
#include <mach/exception.h>
#include <mach/kern_return.h>
#include <mach/vm_param.h>
#include <mach/i386/thread_status.h>
#include <vm/vm_kern.h>
#include <vm/vm_fault.h>
#include <kern/kern_types.h>
#include <kern/processor.h>
#include <kern/thread.h>
#include <kern/task.h>
#include <kern/sched.h>
#include <kern/sched_prim.h>
#include <kern/exception.h>
#include <kern/spl.h>
#include <kern/misc_protos.h>
#include <kern/debug.h>
#if CONFIG_TELEMETRY
#include <kern/telemetry.h>
#endif
#include <sys/kdebug.h>
#include <kperf/kperf.h>
#include <prng/random.h>
#include <string.h>
#include <i386/postcode.h>
#include <i386/mp_desc.h>
#include <i386/proc_reg.h>
#if CONFIG_MCA
#include <i386/machine_check.h>
#endif
#include <mach/i386/syscall_sw.h>
#include <libkern/OSDebug.h>
#include <i386/cpu_threads.h>
#include <machine/pal_routines.h>
extern void throttle_lowpri_io(int);
extern void kprint_state(x86_saved_state64_t *saved_state);
static void user_page_fault_continue(kern_return_t kret);
static void panic_trap(x86_saved_state64_t *saved_state, uint32_t pl, kern_return_t fault_result) __dead2;
static void set_recovery_ip(x86_saved_state64_t *saved_state, vm_offset_t ip);
#if CONFIG_DTRACE
perfCallback tempDTraceTrapHook = NULL;
extern boolean_t dtrace_tally_fault(user_addr_t);
#endif
extern boolean_t pmap_smep_enabled;
extern boolean_t pmap_smap_enabled;
__attribute__((noreturn))
void
thread_syscall_return(
kern_return_t ret)
{
thread_t thr_act = current_thread();
boolean_t is_mach;
int code;
pal_register_cache_state(thr_act, DIRTY);
if (thread_is_64bit_addr(thr_act)) {
x86_saved_state64_t *regs;
regs = USER_REGS64(thr_act);
code = (int) (regs->rax & SYSCALL_NUMBER_MASK);
is_mach = (regs->rax & SYSCALL_CLASS_MASK)
== (SYSCALL_CLASS_MACH << SYSCALL_CLASS_SHIFT);
if (kdebug_enable && is_mach) {
KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE,
MACHDBG_CODE(DBG_MACH_EXCP_SC, code) | DBG_FUNC_END,
ret, 0, 0, 0, 0);
}
regs->rax = ret;
#if DEBUG
if (is_mach) {
DEBUG_KPRINT_SYSCALL_MACH(
"thread_syscall_return: 64-bit mach ret=%u\n",
ret);
} else {
DEBUG_KPRINT_SYSCALL_UNIX(
"thread_syscall_return: 64-bit unix ret=%u\n",
ret);
}
#endif
} else {
x86_saved_state32_t *regs;
regs = USER_REGS32(thr_act);
code = ((int) regs->eax);
is_mach = (code < 0);
if (kdebug_enable && is_mach) {
KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE,
MACHDBG_CODE(DBG_MACH_EXCP_SC, -code) | DBG_FUNC_END,
ret, 0, 0, 0, 0);
}
regs->eax = ret;
#if DEBUG
if (is_mach) {
DEBUG_KPRINT_SYSCALL_MACH(
"thread_syscall_return: 32-bit mach ret=%u\n",
ret);
} else {
DEBUG_KPRINT_SYSCALL_UNIX(
"thread_syscall_return: 32-bit unix ret=%u\n",
ret);
}
#endif
}
#if DEBUG || DEVELOPMENT
kern_allocation_name_t
prior __assert_only = thread_get_kernel_state(thr_act)->allocation_name;
assertf(prior == NULL, "thread_set_allocation_name(\"%s\") not cleared", kern_allocation_get_name(prior));
#endif
throttle_lowpri_io(1);
thread_exception_return();
}
static inline void
user_page_fault_continue(
kern_return_t kr)
{
thread_t thread = current_thread();
user_addr_t vaddr;
if (thread_is_64bit_addr(thread)) {
x86_saved_state64_t *uregs;
uregs = USER_REGS64(thread);
vaddr = (user_addr_t)uregs->cr2;
} else {
x86_saved_state32_t *uregs;
uregs = USER_REGS32(thread);
vaddr = uregs->cr2;
}
pal_dbg_page_fault( thread, vaddr, kr );
i386_exception(EXC_BAD_ACCESS, kr, vaddr);
}
struct recovery {
uintptr_t fault_addr;
uintptr_t recover_addr;
};
extern struct recovery recover_table[];
extern struct recovery recover_table_end[];
const char * trap_type[] = {TRAP_NAMES};
unsigned TRAP_TYPES = sizeof(trap_type) / sizeof(trap_type[0]);
extern void PE_incoming_interrupt(int interrupt);
#if defined(__x86_64__) && DEBUG
void
kprint_state(x86_saved_state64_t *saved_state)
{
kprintf("current_cpu_datap() 0x%lx\n", (uintptr_t)current_cpu_datap());
kprintf("Current GS base MSR 0x%llx\n", rdmsr64(MSR_IA32_GS_BASE));
kprintf("Kernel GS base MSR 0x%llx\n", rdmsr64(MSR_IA32_KERNEL_GS_BASE));
kprintf("state at 0x%lx:\n", (uintptr_t) saved_state);
kprintf(" rdi 0x%llx\n", saved_state->rdi);
kprintf(" rsi 0x%llx\n", saved_state->rsi);
kprintf(" rdx 0x%llx\n", saved_state->rdx);
kprintf(" r10 0x%llx\n", saved_state->r10);
kprintf(" r8 0x%llx\n", saved_state->r8);
kprintf(" r9 0x%llx\n", saved_state->r9);
kprintf(" cr2 0x%llx\n", saved_state->cr2);
kprintf("real cr2 0x%lx\n", get_cr2());
kprintf(" r15 0x%llx\n", saved_state->r15);
kprintf(" r14 0x%llx\n", saved_state->r14);
kprintf(" r13 0x%llx\n", saved_state->r13);
kprintf(" r12 0x%llx\n", saved_state->r12);
kprintf(" r11 0x%llx\n", saved_state->r11);
kprintf(" rbp 0x%llx\n", saved_state->rbp);
kprintf(" rbx 0x%llx\n", saved_state->rbx);
kprintf(" rcx 0x%llx\n", saved_state->rcx);
kprintf(" rax 0x%llx\n", saved_state->rax);
kprintf(" gs 0x%x\n", saved_state->gs);
kprintf(" fs 0x%x\n", saved_state->fs);
kprintf(" isf.trapno 0x%x\n", saved_state->isf.trapno);
kprintf(" isf._pad 0x%x\n", saved_state->isf._pad);
kprintf(" isf.trapfn 0x%llx\n", saved_state->isf.trapfn);
kprintf(" isf.err 0x%llx\n", saved_state->isf.err);
kprintf(" isf.rip 0x%llx\n", saved_state->isf.rip);
kprintf(" isf.cs 0x%llx\n", saved_state->isf.cs);
kprintf(" isf.rflags 0x%llx\n", saved_state->isf.rflags);
kprintf(" isf.rsp 0x%llx\n", saved_state->isf.rsp);
kprintf(" isf.ss 0x%llx\n", saved_state->isf.ss);
}
#endif
uint64_t interrupt_latency_cap = 0;
boolean_t ilat_assert = FALSE;
void
interrupt_latency_tracker_setup(void)
{
uint32_t ilat_cap_us;
if (PE_parse_boot_argn("interrupt_latency_cap_us", &ilat_cap_us, sizeof(ilat_cap_us))) {
interrupt_latency_cap = ilat_cap_us * NSEC_PER_USEC;
nanoseconds_to_absolutetime(interrupt_latency_cap, &interrupt_latency_cap);
} else {
interrupt_latency_cap = LockTimeOut;
}
PE_parse_boot_argn("-interrupt_latency_assert_enable", &ilat_assert, sizeof(ilat_assert));
}
void
interrupt_reset_latency_stats(void)
{
uint32_t i;
for (i = 0; i < real_ncpus; i++) {
cpu_data_ptr[i]->cpu_max_observed_int_latency =
cpu_data_ptr[i]->cpu_max_observed_int_latency_vector = 0;
}
}
void
interrupt_populate_latency_stats(char *buf, unsigned bufsize)
{
uint32_t i, tcpu = ~0;
uint64_t cur_max = 0;
for (i = 0; i < real_ncpus; i++) {
if (cur_max < cpu_data_ptr[i]->cpu_max_observed_int_latency) {
cur_max = cpu_data_ptr[i]->cpu_max_observed_int_latency;
tcpu = i;
}
}
if (tcpu < real_ncpus) {
snprintf(buf, bufsize, "0x%x 0x%x 0x%llx", tcpu, cpu_data_ptr[tcpu]->cpu_max_observed_int_latency_vector, cpu_data_ptr[tcpu]->cpu_max_observed_int_latency);
}
}
uint32_t interrupt_timer_coalescing_enabled = 1;
uint64_t interrupt_coalesced_timers;
void
interrupt(x86_saved_state_t *state)
{
uint64_t rip;
uint64_t rsp;
int interrupt_num;
boolean_t user_mode = FALSE;
int ipl;
int cnum = cpu_number();
cpu_data_t *cdp = cpu_data_ptr[cnum];
int itype = DBG_INTR_TYPE_UNKNOWN;
int handled;
x86_saved_state64_t *state64 = saved_state64(state);
rip = state64->isf.rip;
rsp = state64->isf.rsp;
interrupt_num = state64->isf.trapno;
if (state64->isf.cs & 0x03) {
user_mode = TRUE;
}
if (cpu_data_ptr[cnum]->lcpu.package->num_idle == topoParms.nLThreadsPerPackage) {
cpu_data_ptr[cnum]->cpu_hwIntpexits[interrupt_num]++;
}
if (interrupt_num == (LAPIC_DEFAULT_INTERRUPT_BASE + LAPIC_INTERPROCESSOR_INTERRUPT)) {
itype = DBG_INTR_TYPE_IPI;
} else if (interrupt_num == (LAPIC_DEFAULT_INTERRUPT_BASE + LAPIC_TIMER_INTERRUPT)) {
itype = DBG_INTR_TYPE_TIMER;
} else {
itype = DBG_INTR_TYPE_OTHER;
}
KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE,
MACHDBG_CODE(DBG_MACH_EXCP_INTR, 0) | DBG_FUNC_START,
interrupt_num,
(user_mode ? rip : VM_KERNEL_UNSLIDE(rip)),
user_mode, itype, 0);
SCHED_STATS_INTERRUPT(current_processor());
#if CONFIG_TELEMETRY
if (telemetry_needs_record) {
telemetry_mark_curthread(user_mode, FALSE);
}
#endif
ipl = get_preemption_level();
handled = lapic_interrupt(interrupt_num, state);
if (!handled) {
if (interrupt_num == (LAPIC_DEFAULT_INTERRUPT_BASE + LAPIC_CMCI_INTERRUPT)) {
PE_incoming_interrupt(interrupt_num);
} else if (cnum <= lapic_max_interrupt_cpunum) {
PE_incoming_interrupt((cnum << 8) | interrupt_num);
}
}
if (__improbable(get_preemption_level() != ipl)) {
panic("Preemption level altered by interrupt vector 0x%x: initial 0x%x, final: 0x%x\n", interrupt_num, ipl, get_preemption_level());
}
if (__improbable(cdp->cpu_nested_istack)) {
cdp->cpu_nested_istack_events++;
} else {
uint64_t ctime = mach_absolute_time();
uint64_t int_latency = ctime - cdp->cpu_int_event_time;
uint64_t esdeadline, ehdeadline;
#define TCOAL_ILAT_THRESHOLD (30000ULL)
if ((int_latency < TCOAL_ILAT_THRESHOLD) &&
interrupt_timer_coalescing_enabled) {
esdeadline = cdp->rtclock_timer.queue.earliest_soft_deadline;
ehdeadline = cdp->rtclock_timer.deadline;
if ((ctime >= esdeadline) && (ctime < ehdeadline)) {
interrupt_coalesced_timers++;
TCOAL_DEBUG(0x88880000 | DBG_FUNC_START, ctime, esdeadline, ehdeadline, interrupt_coalesced_timers, 0);
rtclock_intr(state);
TCOAL_DEBUG(0x88880000 | DBG_FUNC_END, ctime, esdeadline, interrupt_coalesced_timers, 0, 0);
} else {
TCOAL_DEBUG(0x77770000, ctime, cdp->rtclock_timer.queue.earliest_soft_deadline, cdp->rtclock_timer.deadline, interrupt_coalesced_timers, 0);
}
}
if (__improbable(ilat_assert && (int_latency > interrupt_latency_cap) && !machine_timeout_suspended())) {
panic("Interrupt vector 0x%x exceeded interrupt latency threshold, 0x%llx absolute time delta, prior signals: 0x%x, current signals: 0x%x", interrupt_num, int_latency, cdp->cpu_prior_signals, cdp->cpu_signals);
}
if (__improbable(int_latency > cdp->cpu_max_observed_int_latency)) {
cdp->cpu_max_observed_int_latency = int_latency;
cdp->cpu_max_observed_int_latency_vector = interrupt_num;
}
}
if (!user_mode) {
uint64_t depth = cdp->cpu_kernel_stack
+ sizeof(struct thread_kernel_state)
+ sizeof(struct i386_exception_link *)
- rsp;
if (__improbable(depth > kernel_stack_depth_max)) {
kernel_stack_depth_max = (vm_offset_t)depth;
KERNEL_DEBUG_CONSTANT(
MACHDBG_CODE(DBG_MACH_SCHED, MACH_STACK_DEPTH),
(long) depth, (long) VM_KERNEL_UNSLIDE(rip), 0, 0, 0);
}
}
if (cnum == master_cpu) {
ml_entropy_collect();
}
#if KPERF
kperf_interrupt();
#endif
KDBG_RELEASE(MACHDBG_CODE(DBG_MACH_EXCP_INTR, 0) | DBG_FUNC_END,
interrupt_num);
assert(ml_get_interrupts_enabled() == FALSE);
}
static inline void
reset_dr7(void)
{
long dr7 = 0x400;
__asm__ volatile ("mov %0,%%dr7" : : "r" (dr7));
}
#if MACH_KDP
unsigned kdp_has_active_watchpoints = 0;
#define NO_WATCHPOINTS (!kdp_has_active_watchpoints)
#else
#define NO_WATCHPOINTS 1
#endif
void
kernel_trap(
x86_saved_state_t *state,
uintptr_t *lo_spp)
{
x86_saved_state64_t *saved_state;
int code;
user_addr_t vaddr;
int type;
vm_map_t map = 0;
kern_return_t result = KERN_FAILURE;
kern_return_t fault_result = KERN_SUCCESS;
thread_t thread;
boolean_t intr;
vm_prot_t prot;
struct recovery *rp;
vm_offset_t kern_ip;
#if NCOPY_WINDOWS > 0
int fault_in_copy_window = -1;
#endif
int is_user;
int trap_pl = get_preemption_level();
thread = current_thread();
if (__improbable(is_saved_state32(state))) {
panic("kernel_trap(%p) with 32-bit state", state);
}
saved_state = saved_state64(state);
saved_state->isf.cpu = cpu_number();
vaddr = (user_addr_t)saved_state->cr2;
type = saved_state->isf.trapno;
code = (int)(saved_state->isf.err & 0xffff);
intr = (saved_state->isf.rflags & EFL_IF) != 0;
kern_ip = (vm_offset_t)saved_state->isf.rip;
is_user = (vaddr < VM_MAX_USER_PAGE_ADDRESS);
#if CONFIG_DTRACE
if (__improbable(tempDTraceTrapHook != NULL)) {
if (tempDTraceTrapHook(type, state, lo_spp, 0) == KERN_SUCCESS) {
return;
}
}
#endif
if (__improbable(T_PREEMPT == type)) {
ast_taken_kernel();
KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE,
(MACHDBG_CODE(DBG_MACH_EXCP_KTRAP_x86, type)) | DBG_FUNC_NONE,
0, 0, 0, VM_KERNEL_UNSLIDE(kern_ip), 0);
return;
}
user_addr_t kd_vaddr = is_user ? vaddr : VM_KERNEL_UNSLIDE(vaddr);
KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE,
(MACHDBG_CODE(DBG_MACH_EXCP_KTRAP_x86, type)) | DBG_FUNC_NONE,
(unsigned)(kd_vaddr >> 32), (unsigned)kd_vaddr, is_user,
VM_KERNEL_UNSLIDE(kern_ip), 0);
if (T_PAGE_FAULT == type) {
map = kernel_map;
if (__probable(thread != THREAD_NULL && thread->map != kernel_map)) {
#if NCOPY_WINDOWS > 0
vm_offset_t copy_window_base;
vm_offset_t kvaddr;
int window_index;
kvaddr = (vm_offset_t)vaddr;
copy_window_base = current_cpu_datap()->cpu_copywindow_base;
if (kvaddr >= copy_window_base && kvaddr < (copy_window_base + (NBPDE * NCOPY_WINDOWS))) {
window_index = (int)((kvaddr - copy_window_base) / NBPDE);
if (thread->machine.copy_window[window_index].user_base != (user_addr_t)-1) {
kvaddr -= (copy_window_base + (NBPDE * window_index));
vaddr = thread->machine.copy_window[window_index].user_base + kvaddr;
map = thread->map;
fault_in_copy_window = window_index;
}
}
#else
if (__probable(vaddr < VM_MAX_USER_PAGE_ADDRESS)) {
map = thread->map;
if (__improbable((code == (T_PF_PROT | T_PF_EXECUTE)) &&
(pmap_smep_enabled) && (saved_state->isf.rip == vaddr))) {
goto debugger_entry;
}
if (__improbable(code & T_PF_PROT &&
pmap_smap_enabled &&
(saved_state->isf.rflags & EFL_AC) == 0)) {
goto debugger_entry;
}
if (no_shared_cr3 &&
(thread->machine.specFlags & CopyIOActive) &&
map->pmap->pm_cr3 != get_cr3_base()) {
pmap_assert(current_cpu_datap()->cpu_pmap_pcid_enabled == FALSE);
set_cr3_raw(map->pmap->pm_cr3);
return;
}
if (__improbable(vaddr < PAGE_SIZE) &&
((thread->machine.specFlags & CopyIOActive) == 0)) {
goto debugger_entry;
}
}
#endif
}
}
(void) ml_set_interrupts_enabled(intr);
switch (type) {
case T_NO_FPU:
fpnoextflt();
return;
case T_FPU_FAULT:
fpextovrflt();
return;
case T_FLOATING_POINT_ERROR:
fpexterrflt();
return;
case T_SSE_FLOAT_ERROR:
fpSSEexterrflt();
return;
case T_INVALID_OPCODE:
fpUDflt(kern_ip);
goto debugger_entry;
case T_DEBUG:
if ((saved_state->isf.rflags & EFL_TF) == 0 && NO_WATCHPOINTS) {
reset_dr7();
return;
}
goto debugger_entry;
case T_INT3:
goto debugger_entry;
case T_PAGE_FAULT:
#if CONFIG_DTRACE
if (thread != THREAD_NULL && thread->t_dtrace_inprobe) {
if (dtrace_tally_fault(vaddr)) {
goto FALL_THROUGH;
}
}
#endif
prot = VM_PROT_READ;
if (code & T_PF_WRITE) {
prot |= VM_PROT_WRITE;
}
if (code & T_PF_EXECUTE) {
prot |= VM_PROT_EXECUTE;
}
fault_result = result = vm_fault(map,
vaddr,
prot,
FALSE, VM_KERN_MEMORY_NONE,
THREAD_UNINT, NULL, 0);
if (result == KERN_SUCCESS) {
#if NCOPY_WINDOWS > 0
if (fault_in_copy_window != -1) {
ml_set_interrupts_enabled(FALSE);
copy_window_fault(thread, map,
fault_in_copy_window);
(void) ml_set_interrupts_enabled(intr);
}
#endif
return;
}
#if CONFIG_DTRACE
FALL_THROUGH:
#endif
case T_GENERAL_PROTECTION:
for (rp = recover_table; rp < recover_table_end; rp++) {
if (kern_ip == rp->fault_addr) {
set_recovery_ip(saved_state, rp->recover_addr);
return;
}
}
if (thread != THREAD_NULL && thread->recover) {
set_recovery_ip(saved_state, thread->recover);
thread->recover = 0;
return;
}
default:
if (type == 15) {
kprintf("kernel_trap() ignoring spurious trap 15\n");
return;
}
debugger_entry:
sync_iss_to_iks(state);
#if MACH_KDP
if (kdp_i386_trap(type, saved_state, result, (vm_offset_t)vaddr)) {
return;
}
#endif
}
pal_cli();
panic_trap(saved_state, trap_pl, fault_result);
}
static void
set_recovery_ip(x86_saved_state64_t *saved_state, vm_offset_t ip)
{
saved_state->isf.rip = ip;
}
static void
panic_trap(x86_saved_state64_t *regs, uint32_t pl, kern_return_t fault_result)
{
const char *trapname = "Unknown";
pal_cr_t cr0, cr2, cr3, cr4;
boolean_t potential_smep_fault = FALSE, potential_kernel_NX_fault = FALSE;
boolean_t potential_smap_fault = FALSE;
pal_get_control_registers( &cr0, &cr2, &cr3, &cr4 );
assert(ml_get_interrupts_enabled() == FALSE);
current_cpu_datap()->cpu_fatal_trap_state = regs;
panic_io_port_read();
kprintf("CPU %d panic trap number 0x%x, rip 0x%016llx\n",
cpu_number(), regs->isf.trapno, regs->isf.rip);
kprintf("cr0 0x%016llx cr2 0x%016llx cr3 0x%016llx cr4 0x%016llx\n",
cr0, cr2, cr3, cr4);
if (regs->isf.trapno < TRAP_TYPES) {
trapname = trap_type[regs->isf.trapno];
}
if ((regs->isf.trapno == T_PAGE_FAULT) && (regs->isf.err == (T_PF_PROT | T_PF_EXECUTE)) && (regs->isf.rip == regs->cr2)) {
if (pmap_smep_enabled && (regs->isf.rip < VM_MAX_USER_PAGE_ADDRESS)) {
potential_smep_fault = TRUE;
} else if (regs->isf.rip >= VM_MIN_KERNEL_AND_KEXT_ADDRESS) {
potential_kernel_NX_fault = TRUE;
}
} else if (pmap_smap_enabled &&
regs->isf.trapno == T_PAGE_FAULT &&
regs->isf.err & T_PF_PROT &&
regs->cr2 < VM_MAX_USER_PAGE_ADDRESS &&
regs->isf.rip >= VM_MIN_KERNEL_AND_KEXT_ADDRESS) {
potential_smap_fault = TRUE;
}
#undef panic
panic("Kernel trap at 0x%016llx, type %d=%s, registers:\n"
"CR0: 0x%016llx, CR2: 0x%016llx, CR3: 0x%016llx, CR4: 0x%016llx\n"
"RAX: 0x%016llx, RBX: 0x%016llx, RCX: 0x%016llx, RDX: 0x%016llx\n"
"RSP: 0x%016llx, RBP: 0x%016llx, RSI: 0x%016llx, RDI: 0x%016llx\n"
"R8: 0x%016llx, R9: 0x%016llx, R10: 0x%016llx, R11: 0x%016llx\n"
"R12: 0x%016llx, R13: 0x%016llx, R14: 0x%016llx, R15: 0x%016llx\n"
"RFL: 0x%016llx, RIP: 0x%016llx, CS: 0x%016llx, SS: 0x%016llx\n"
"Fault CR2: 0x%016llx, Error code: 0x%016llx, Fault CPU: 0x%x%s%s%s%s, PL: %d, VF: %d\n",
regs->isf.rip, regs->isf.trapno, trapname,
cr0, cr2, cr3, cr4,
regs->rax, regs->rbx, regs->rcx, regs->rdx,
regs->isf.rsp, regs->rbp, regs->rsi, regs->rdi,
regs->r8, regs->r9, regs->r10, regs->r11,
regs->r12, regs->r13, regs->r14, regs->r15,
regs->isf.rflags, regs->isf.rip, regs->isf.cs & 0xFFFF,
regs->isf.ss & 0xFFFF, regs->cr2, regs->isf.err, regs->isf.cpu,
virtualized ? " VMM" : "",
potential_kernel_NX_fault ? " Kernel NX fault" : "",
potential_smep_fault ? " SMEP/User NX fault" : "",
potential_smap_fault ? " SMAP fault" : "",
pl,
fault_result);
}
#if CONFIG_DTRACE
extern kern_return_t dtrace_user_probe(x86_saved_state_t *);
#endif
#if DEBUG
uint32_t fsigs[2];
uint32_t fsigns, fsigcs;
#endif
void
user_trap(
x86_saved_state_t *saved_state)
{
int exc;
int err;
mach_exception_code_t code;
mach_exception_subcode_t subcode;
int type;
user_addr_t vaddr;
vm_prot_t prot;
thread_t thread = current_thread();
kern_return_t kret;
user_addr_t rip;
unsigned long dr6 = 0;
assert((is_saved_state32(saved_state) && !thread_is_64bit_addr(thread)) ||
(is_saved_state64(saved_state) && thread_is_64bit_addr(thread)));
if (is_saved_state64(saved_state)) {
x86_saved_state64_t *regs;
regs = saved_state64(saved_state);
regs->isf.cpu = cpu_number();
type = regs->isf.trapno;
err = (int)regs->isf.err & 0xffff;
vaddr = (user_addr_t)regs->cr2;
rip = (user_addr_t)regs->isf.rip;
} else {
x86_saved_state32_t *regs;
regs = saved_state32(saved_state);
regs->cpu = cpu_number();
type = regs->trapno;
err = regs->err & 0xffff;
vaddr = (user_addr_t)regs->cr2;
rip = (user_addr_t)regs->eip;
}
if ((type == T_DEBUG) && thread->machine.ids) {
unsigned long clear = 0;
__asm__ volatile ("mov %%db6, %0" : "=r" (dr6));
__asm__ volatile ("mov %0, %%db6" : : "r" (clear));
}
pal_sti();
KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE,
(MACHDBG_CODE(DBG_MACH_EXCP_UTRAP_x86, type)) | DBG_FUNC_NONE,
(unsigned)(vaddr >> 32), (unsigned)vaddr,
(unsigned)(rip >> 32), (unsigned)rip, 0);
code = 0;
subcode = 0;
exc = 0;
#if CONFIG_DTRACE
#endif
DEBUG_KPRINT_SYSCALL_MASK(1,
"user_trap: type=0x%x(%s) err=0x%x cr2=%p rip=%p\n",
type, trap_type[type], err, (void *)(long) vaddr, (void *)(long) rip);
switch (type) {
case T_DIVIDE_ERROR:
exc = EXC_ARITHMETIC;
code = EXC_I386_DIV;
break;
case T_DEBUG:
{
pcb_t pcb;
pcb = THREAD_TO_PCB(thread);
if (pcb->ids) {
if (thread_is_64bit_addr(thread)) {
x86_debug_state64_t *ids = pcb->ids;
ids->dr6 = dr6;
} else {
x86_debug_state32_t *ids = pcb->ids;
ids->dr6 = (uint32_t) dr6;
}
}
exc = EXC_BREAKPOINT;
code = EXC_I386_SGL;
break;
}
case T_INT3:
#if CONFIG_DTRACE
if (dtrace_user_probe(saved_state) == KERN_SUCCESS) {
return;
}
#endif
exc = EXC_BREAKPOINT;
code = EXC_I386_BPT;
break;
case T_OVERFLOW:
exc = EXC_ARITHMETIC;
code = EXC_I386_INTO;
break;
case T_OUT_OF_BOUNDS:
exc = EXC_SOFTWARE;
code = EXC_I386_BOUND;
break;
case T_INVALID_OPCODE:
#if !defined(RC_HIDE_XNU_J137)
fpUDflt(rip);
#endif
exc = EXC_BAD_INSTRUCTION;
code = EXC_I386_INVOP;
break;
case T_NO_FPU:
fpnoextflt();
return;
case T_FPU_FAULT:
fpextovrflt();
return;
case T_INVALID_TSS:
exc = EXC_BAD_INSTRUCTION;
code = EXC_I386_INVTSSFLT;
subcode = err;
break;
case T_SEGMENT_NOT_PRESENT:
exc = EXC_BAD_INSTRUCTION;
code = EXC_I386_SEGNPFLT;
subcode = err;
break;
case T_STACK_FAULT:
exc = EXC_BAD_INSTRUCTION;
code = EXC_I386_STKFLT;
subcode = err;
break;
case T_GENERAL_PROTECTION:
exc = EXC_BAD_ACCESS;
code = EXC_I386_GPFLT;
subcode = err;
break;
case T_PAGE_FAULT:
{
prot = VM_PROT_READ;
if (err & T_PF_WRITE) {
prot |= VM_PROT_WRITE;
}
if (__improbable(err & T_PF_EXECUTE)) {
prot |= VM_PROT_EXECUTE;
}
#if DEVELOPMENT || DEBUG
uint32_t fsig = 0;
fsig = thread_fpsimd_hash(thread);
#if DEBUG
fsigs[0] = fsig;
#endif
#endif
kret = vm_fault(thread->map,
vaddr,
prot, FALSE, VM_KERN_MEMORY_NONE,
THREAD_ABORTSAFE, NULL, 0);
#if DEVELOPMENT || DEBUG
if (fsig) {
uint32_t fsig2 = thread_fpsimd_hash(thread);
#if DEBUG
fsigcs++;
fsigs[1] = fsig2;
#endif
if (fsig != fsig2) {
panic("FP/SIMD state hash mismatch across fault thread: %p 0x%x->0x%x", thread, fsig, fsig2);
}
} else {
#if DEBUG
fsigns++;
#endif
}
#endif
if (__probable((kret == KERN_SUCCESS) || (kret == KERN_ABORTED))) {
thread_exception_return();
}
if (__improbable(kret == KERN_FAILURE)) {
panic("vm_fault() KERN_FAILURE from user fault on thread %p", thread);
}
user_page_fault_continue(kret);
}
break;
case T_SSE_FLOAT_ERROR:
fpSSEexterrflt();
return;
case T_FLOATING_POINT_ERROR:
fpexterrflt();
return;
case T_DTRACE_RET:
#if CONFIG_DTRACE
if (dtrace_user_probe(saved_state) == KERN_SUCCESS) {
return;
}
#endif
exc = EXC_BAD_INSTRUCTION;
code = EXC_I386_INVOP;
break;
default:
panic("Unexpected user trap, type %d", type);
}
i386_exception(exc, code, subcode);
}
void
i386_exception(
int exc,
mach_exception_code_t code,
mach_exception_subcode_t subcode)
{
mach_exception_data_type_t codes[EXCEPTION_CODE_MAX];
DEBUG_KPRINT_SYSCALL_MACH("i386_exception: exc=%d code=0x%llx subcode=0x%llx\n",
exc, code, subcode);
codes[0] = code;
codes[1] = subcode;
exception_triage(exc, codes, 2);
}
void
sync_iss_to_iks(x86_saved_state_t *saved_state)
{
struct x86_kernel_state *iks = NULL;
vm_offset_t kstack;
boolean_t record_active_regs = FALSE;
if (saved_state && saved_state->flavor == THREAD_STATE_NONE) {
pal_get_kern_regs( saved_state );
}
if (current_thread() != NULL &&
(kstack = current_thread()->kernel_stack) != 0) {
x86_saved_state64_t *regs = saved_state64(saved_state);
iks = STACK_IKS(kstack);
if (saved_state == NULL ||
regs == USER_REGS64(current_thread())) {
record_active_regs = TRUE;
} else {
iks->k_rbx = regs->rbx;
iks->k_rsp = regs->isf.rsp;
iks->k_rbp = regs->rbp;
iks->k_r12 = regs->r12;
iks->k_r13 = regs->r13;
iks->k_r14 = regs->r14;
iks->k_r15 = regs->r15;
iks->k_rip = regs->isf.rip;
}
}
if (record_active_regs == TRUE) {
__asm__ volatile ("movq %%rbx, %0" : "=m" (iks->k_rbx));
__asm__ volatile ("movq %%rsp, %0" : "=m" (iks->k_rsp));
__asm__ volatile ("movq %%rbp, %0" : "=m" (iks->k_rbp));
__asm__ volatile ("movq %%r12, %0" : "=m" (iks->k_r12));
__asm__ volatile ("movq %%r13, %0" : "=m" (iks->k_r13));
__asm__ volatile ("movq %%r14, %0" : "=m" (iks->k_r14));
__asm__ volatile ("movq %%r15, %0" : "=m" (iks->k_r15));
__asm__ volatile ("leaq 1f(%%rip), %%rax; mov %%rax, %0\n1:"
: "=m" (iks->k_rip)
:
: "rax");
}
}
void
sync_iss_to_iks_unconditionally(__unused x86_saved_state_t *saved_state)
{
struct x86_kernel_state *iks;
vm_offset_t kstack;
if ((kstack = current_thread()->kernel_stack) != 0) {
iks = STACK_IKS(kstack);
__asm__ volatile ("movq %%rbx, %0" : "=m" (iks->k_rbx));
__asm__ volatile ("movq %%rsp, %0" : "=m" (iks->k_rsp));
__asm__ volatile ("movq %%rbp, %0" : "=m" (iks->k_rbp));
__asm__ volatile ("movq %%r12, %0" : "=m" (iks->k_r12));
__asm__ volatile ("movq %%r13, %0" : "=m" (iks->k_r13));
__asm__ volatile ("movq %%r14, %0" : "=m" (iks->k_r14));
__asm__ volatile ("movq %%r15, %0" : "=m" (iks->k_r15));
__asm__ volatile ("leaq 1f(%%rip), %%rax; mov %%rax, %0\n1:" : "=m" (iks->k_rip)::"rax");
}
}
#if DEBUG
#define TERI 1
#endif
#if TERI
extern void thread_exception_return_internal(void) __dead2;
void
thread_exception_return(void)
{
thread_t thread = current_thread();
ml_set_interrupts_enabled(FALSE);
if (thread_is_64bit_addr(thread) != task_has_64Bit_addr(thread->task)) {
panic("Task/thread bitness mismatch %p %p, task: %d, thread: %d", thread, thread->task, thread_is_64bit_addr(thread), task_has_64Bit_addr(thread->task));
}
if (thread_is_64bit_addr(thread)) {
if ((gdt_desc_p(USER64_CS)->access & ACC_PL_U) == 0) {
panic("64-GDT mismatch %p, descriptor: %p", thread, gdt_desc_p(USER64_CS));
}
} else {
if ((gdt_desc_p(USER_CS)->access & ACC_PL_U) == 0) {
panic("32-GDT mismatch %p, descriptor: %p", thread, gdt_desc_p(USER_CS));
}
}
assert(get_preemption_level() == 0);
thread_exception_return_internal();
}
#endif