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* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
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* may not be used to create, or enable the creation or redistribution of,
* unlawful or unlicensed copies of an Apple operating system, or to
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*
* Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this file.
*
* The Original Code and all software distributed under the License are
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*/
/*
* file: pe_kprintf.c
* i386 platform expert debugging output initialization.
*/
#include <stdarg.h>
#include <machine/machine_routines.h>
#include <pexpert/pexpert.h>
#include <kern/debug.h>
#include <kern/simple_lock.h>
#include <i386/machine_cpu.h>
#include <i386/mp.h>
#include <machine/pal_routines.h>
#include <i386/proc_reg.h>
#include <os/log_private.h>
#include <libkern/section_keywords.h>
#include <kern/processor.h>
#include <kern/clock.h>
#include <mach/clock_types.h>
extern uint64_t LockTimeOut;
/* Globals */
typedef void (*PE_kputc_t)(char);
#if XNU_TARGET_OS_OSX
PE_kputc_t PE_kputc;
#else
SECURITY_READ_ONLY_LATE(PE_kputc_t) PE_kputc;
#endif
#if DEVELOPMENT || DEBUG
/* DEBUG kernel starts with true serial, but
* may later disable or switch to video
* console */
SECURITY_READ_ONLY_LATE(bool) disable_serial_output = false;
#else
SECURITY_READ_ONLY_LATE(bool) disable_serial_output = true;
#endif
SECURITY_READ_ONLY_LATE(bool) disable_iolog_serial_output = false;
SECURITY_READ_ONLY_LATE(bool) enable_dklog_serial_output = false;
static SIMPLE_LOCK_DECLARE(kprintf_lock, 0);
__startup_func
static void
PE_init_kprintf(void)
{
if (PE_state.initialized == FALSE) {
panic("Platform Expert not initialized");
}
bool new_disable_serial_output = true;
if (debug_boot_arg & DB_KPRT) {
new_disable_serial_output = false;
}
/* If we are newly enabling serial, make sure we only
* call pal_serial_init() if our previous state was
* not enabled */
if (!new_disable_serial_output && (!disable_serial_output || pal_serial_init())) {
PE_kputc = pal_serial_putc;
} else {
PE_kputc = console_write_unbuffered;
}
disable_serial_output = new_disable_serial_output;
}
STARTUP(KPRINTF, STARTUP_RANK_FIRST, PE_init_kprintf);
#if CONFIG_NO_KPRINTF_STRINGS
/* Prevent CPP from breaking the definition below */
#undef kprintf
#endif
#ifdef MP_DEBUG
static void
_kprintf(const char *format, ...)
{
va_list listp;
va_start(listp, format);
_doprnt(format, &listp, PE_kputc, 16);
va_end(listp);
}
#define MP_DEBUG_KPRINTF(x...) _kprintf(x)
#else /* MP_DEBUG */
#define MP_DEBUG_KPRINTF(x...)
#endif /* MP_DEBUG */
static int cpu_last_locked = 0;
#define KPRINTF_LOCKWAIT_PATIENT (LockTimeOut)
#define KPRINTF_LOCKWAIT_IMPATIENT (LockTimeOut >> 4)
__attribute__((noinline, not_tail_called))
void
kprintf(const char *fmt, ...)
{
va_list listp;
va_list listp2;
boolean_t state;
boolean_t in_panic_context = FALSE;
unsigned int kprintf_lock_grabbed;
void *caller = __builtin_return_address(0);
if (!disable_serial_output) {
boolean_t early = FALSE;
uint64_t gsbase = rdmsr64(MSR_IA32_GS_BASE);
if (gsbase == EARLY_GSBASE_MAGIC || gsbase == 0) {
early = TRUE;
}
/* If PE_kputc has not yet been initialized, don't
* take any locks, just dump to serial */
if (!PE_kputc || early) {
va_start(listp, fmt);
va_copy(listp2, listp);
_doprnt_log(fmt, &listp, pal_serial_putc, 16);
va_end(listp);
// If interrupts are enabled
if (ml_get_interrupts_enabled()) {
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wformat-nonliteral"
os_log_with_args(OS_LOG_DEFAULT, OS_LOG_TYPE_DEFAULT, fmt, listp2, caller);
#pragma clang diagnostic pop
}
va_end(listp2);
return;
}
va_start(listp, fmt);
va_copy(listp2, listp);
state = ml_set_interrupts_enabled(FALSE);
pal_preemption_assert();
in_panic_context = debug_is_current_cpu_in_panic_state();
// If current CPU is in panic context, be a little more impatient.
kprintf_lock_grabbed = simple_lock_try_lock_mp_signal_safe_loop_duration(&kprintf_lock,
in_panic_context ? KPRINTF_LOCKWAIT_IMPATIENT : KPRINTF_LOCKWAIT_PATIENT,
LCK_GRP_NULL);
if (cpu_number() != cpu_last_locked) {
MP_DEBUG_KPRINTF("[cpu%d...]\n", cpu_number());
cpu_last_locked = cpu_number();
}
_doprnt(fmt, &listp, PE_kputc, 16);
if (kprintf_lock_grabbed) {
simple_unlock(&kprintf_lock);
}
ml_set_interrupts_enabled(state);
va_end(listp);
// If interrupts are enabled
if (ml_get_interrupts_enabled()) {
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wformat-nonliteral"
os_log_with_args(OS_LOG_DEFAULT, OS_LOG_TYPE_DEFAULT, fmt, listp2, caller);
#pragma clang diagnostic pop
}
va_end(listp2);
} else {
if (ml_get_interrupts_enabled()) {
va_start(listp, fmt);
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wformat-nonliteral"
os_log_with_args(OS_LOG_DEFAULT, OS_LOG_TYPE_DEFAULT, fmt, listp, caller);
#pragma clang diagnostic pop
va_end(listp);
}
}
}
extern void kprintf_break_lock(void);
void
kprintf_break_lock(void)
{
simple_lock_init(&kprintf_lock, 0);
}