[apple/xnu.git] / libkern / gen / OSDebug.cpp

/*
 * Copyright (c) 2005 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 * 
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */

// NOTE:  This file is only c++ so I can get static initialisers going
#include <libkern/OSDebug.h>

#include <sys/cdefs.h>

#include <stdarg.h>
#include <mach/mach_types.h>
#include <mach/kmod.h>
#include <kern/locks.h>

#include <libkern/libkern.h>	// From bsd's libkern directory
#include <mach/vm_param.h>

#include <sys/kdebug.h>
#include <kern/thread.h>

extern int etext;
__BEGIN_DECLS
// From osmfk/kern/thread.h but considered to be private
extern vm_offset_t min_valid_stack_address(void);
extern vm_offset_t max_valid_stack_address(void);

// From osfmk/kmod.c
extern void kmod_dump_log(vm_offset_t *addr, unsigned int cnt);

extern addr64_t kvtophys(vm_offset_t va);

__END_DECLS

extern lck_grp_t *IOLockGroup;

static lck_mtx_t *sOSReportLock = lck_mtx_alloc_init(IOLockGroup, LCK_ATTR_NULL);

/* Use kernel_debug() to log a backtrace */ 
void
trace_backtrace(uint32_t debugid, uint32_t debugid2, uintptr_t size, uintptr_t data) {
	void *bt[16];
	const unsigned cnt = sizeof(bt) / sizeof(bt[0]);
  	unsigned i;
	int found = 0;

	OSBacktrace(bt, cnt);	
  
	/* find first non-kernel frame */
  	for (i = 3; i < cnt && bt[i]; i++) {
 		if (bt[i] > (void*)&etext) {
			found = 1;
  			break;
		}
	}
	/* 
	 * if there are non-kernel frames, only log these
	 * otherwise, log everything but the first two
	 */
	if (!found) i=2;

#define safe_bt(a) (uintptr_t)(a<cnt ? bt[a] : 0)
	kernel_debug(debugid, data, size, safe_bt(i), safe_bt(i+1), 0);
	kernel_debug(debugid2, safe_bt(i+2), safe_bt(i+3), safe_bt(i+4), safe_bt(i+5), 0);
}

/* Report a message with a 4 entry backtrace - very slow */
void
OSReportWithBacktrace(const char *str, ...)
{
    char buf[128];
    void *bt[9];
    const unsigned cnt = sizeof(bt) / sizeof(bt[0]);
    va_list listp;

    // Ignore the our and our callers stackframes, skipping frames 0 & 1
    (void) OSBacktrace(bt, cnt);

    va_start(listp, str);
    vsnprintf(buf, sizeof(buf), str, listp);
    va_end(listp);

    lck_mtx_lock(sOSReportLock);
    {
        printf("%s\nBacktrace %p %p %p %p %p %p %p\n",
            buf, bt[2], bt[3], bt[4], bt[5], bt[6], bt[7], bt[8]);
        kmod_dump_log((vm_offset_t *) &bt[2], cnt - 2);
    }
    lck_mtx_unlock(sOSReportLock);
}

static vm_offset_t minstackaddr = min_valid_stack_address();
static vm_offset_t maxstackaddr = max_valid_stack_address();

#if __i386__
#define i386_RETURN_OFFSET 4

static unsigned int
i386_validate_stackptr(vm_offset_t stackptr)
{
	/* Existence and alignment check
	 */
	if (!stackptr || (stackptr & 0x3))
		return 0;
  
	/* Is a virtual->physical translation present?
	 */
	if (!kvtophys(stackptr))
		return 0;
  
	/* Check if the return address lies on the same page;
	 * If not, verify that a translation exists.
	 */
	if (((PAGE_SIZE - (stackptr & PAGE_MASK)) < i386_RETURN_OFFSET) &&
	    !kvtophys(stackptr + i386_RETURN_OFFSET))
		return 0;
	return 1;
}

static unsigned int
i386_validate_raddr(vm_offset_t raddr)
{
	return ((raddr > VM_MIN_KERNEL_AND_KEXT_ADDRESS) &&
	    (raddr < VM_MAX_KERNEL_ADDRESS));
}
#endif

#if __x86_64__
#define x86_64_RETURN_OFFSET 8
static unsigned int
x86_64_validate_raddr(vm_offset_t raddr)
{
	return ((raddr > VM_MIN_KERNEL_AND_KEXT_ADDRESS) &&
	    (raddr < VM_MAX_KERNEL_ADDRESS));
}
static unsigned int
x86_64_validate_stackptr(vm_offset_t stackptr)
{
	/* Existence and alignment check
	 */
	if (!stackptr || (stackptr & 0x7) || !x86_64_validate_raddr(stackptr))
		return 0;
  
	/* Is a virtual->physical translation present?
	 */
	if (!kvtophys(stackptr))
		return 0;
  
	/* Check if the return address lies on the same page;
	 * If not, verify that a translation exists.
	 */
	if (((PAGE_SIZE - (stackptr & PAGE_MASK)) < x86_64_RETURN_OFFSET) &&
	    !kvtophys(stackptr + x86_64_RETURN_OFFSET))
		return 0;
	return 1;
}
#endif


unsigned OSBacktrace(void **bt, unsigned maxAddrs)
{
    unsigned frame;

#if __ppc__
    vm_offset_t stackptr, stackptr_prev;
    const vm_offset_t * const mem = (vm_offset_t *) 0;
    unsigned i = 0;

    __asm__ volatile("mflr %0" : "=r" (stackptr)); 
    bt[i++] = (void *) stackptr;

    __asm__ volatile("mr %0,r1" : "=r" (stackptr)); 
    for ( ; i < maxAddrs; i++) {
	// Validate we have a reasonable stackptr
	if ( !(minstackaddr <= stackptr && stackptr < maxstackaddr)
	|| (stackptr & 3))
	    break;

	stackptr_prev = stackptr;
	stackptr = mem[stackptr_prev >> 2];
	if ((stackptr - stackptr_prev) > 8 * 1024)	// Sanity check
	    break;

	vm_offset_t addr = mem[(stackptr >> 2) + 2]; 
	if ((addr & 3) || (addr < 0x8000))	// More sanity checks
	    break;
	bt[i] = (void *) addr;
    }
    frame = i;

    for ( ; i < maxAddrs; i++)
	    bt[i] = (void *) 0;
#elif __i386__
#define SANE_i386_FRAME_SIZE (kernel_stack_size >> 1)
    vm_offset_t stackptr, stackptr_prev, raddr;
    unsigned frame_index = 0;
/* Obtain current frame pointer */
    __asm__ volatile("movl %%ebp, %0" : "=m" (stackptr)); 

    if (!i386_validate_stackptr(stackptr))
	    goto pad;

    raddr = *((vm_offset_t *) (stackptr + i386_RETURN_OFFSET));

    if (!i386_validate_raddr(raddr))
	    goto pad;

    bt[frame_index++] = (void *) raddr;

    for ( ; frame_index < maxAddrs; frame_index++) {
	    stackptr_prev = stackptr;
	    stackptr = *((vm_offset_t *) stackptr_prev);

	    if (!i386_validate_stackptr(stackptr))
		    break;
	/* Stack grows downwards */
	    if (stackptr < stackptr_prev)
		    break;

	    if ((stackptr - stackptr_prev) > SANE_i386_FRAME_SIZE)
		    break;

	    raddr = *((vm_offset_t *) (stackptr + i386_RETURN_OFFSET));

	    if (!i386_validate_raddr(raddr))
		    break;

	    bt[frame_index] = (void *) raddr;
    }
pad:
    frame = frame_index;

    for ( ; frame_index < maxAddrs; frame_index++)
	    bt[frame_index] = (void *) 0;
#elif __x86_64__
#define SANE_x86_64_FRAME_SIZE (kernel_stack_size >> 1)
    vm_offset_t stackptr, stackptr_prev, raddr;
    unsigned frame_index = 0;
/* Obtain current frame pointer */

    __asm__ volatile("movq %%rbp, %0" : "=m" (stackptr)); 

    if (!x86_64_validate_stackptr(stackptr))
	    goto pad;

    raddr = *((vm_offset_t *) (stackptr + x86_64_RETURN_OFFSET));

    if (!x86_64_validate_raddr(raddr))
	    goto pad;

    bt[frame_index++] = (void *) raddr;

    for ( ; frame_index < maxAddrs; frame_index++) {
	    stackptr_prev = stackptr;
	    stackptr = *((vm_offset_t *) stackptr_prev);

	    if (!x86_64_validate_stackptr(stackptr))
		    break;
	/* Stack grows downwards */
	    if (stackptr < stackptr_prev)
		    break;

	    if ((stackptr - stackptr_prev) > SANE_x86_64_FRAME_SIZE)
		    break;

	    raddr = *((vm_offset_t *) (stackptr + x86_64_RETURN_OFFSET));

	    if (!x86_64_validate_raddr(raddr))
		    break;

	    bt[frame_index] = (void *) raddr;
    }
pad:
    frame = frame_index;

    for ( ; frame_index < maxAddrs; frame_index++)
	    bt[frame_index] = (void *) 0;
#else
#error arch
#endif
    return frame;
}
Commit	Line	Data
91447636 A	1	/*
	2	* Copyright (c) 2005 Apple Computer, Inc. All rights reserved.
	3	*
2d21ac55	4	* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
91447636	5	*
2d21ac55 A	6	* This file contains Original Code and/or Modifications of Original Code
	7	* as defined in and that are subject to the Apple Public Source License
	8	* Version 2.0 (the 'License'). You may not use this file except in
	9	* compliance with the License. The rights granted to you under the License
	10	* may not be used to create, or enable the creation or redistribution of,
	11	* unlawful or unlicensed copies of an Apple operating system, or to
	12	* circumvent, violate, or enable the circumvention or violation of, any
	13	* terms of an Apple operating system software license agreement.
8f6c56a5	14	*
2d21ac55 A	15	* Please obtain a copy of the License at
	16	* http://www.opensource.apple.com/apsl/ and read it before using this file.
	17	*
	18	* The Original Code and all software distributed under the License are
	19	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
8f6c56a5 A	20	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
8f6c56a5 A	21	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
2d21ac55 A	22	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	23	* Please see the License for the specific language governing rights and
	24	* limitations under the License.
8f6c56a5	25	*
2d21ac55	26	* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
91447636 A	27	*/
	28
	29	// NOTE: This file is only c++ so I can get static initialisers going
	30	#include <libkern/OSDebug.h>
	31
	32	#include <sys/cdefs.h>
	33
	34	#include <stdarg.h>
	35	#include <mach/mach_types.h>
	36	#include <mach/kmod.h>
b0d623f7	37	#include <kern/locks.h>
91447636 A	38
91447636 A	39	#include <libkern/libkern.h> // From bsd's libkern directory
0c530ab8	40	#include <mach/vm_param.h>
91447636	41
2d21ac55	42	#include <sys/kdebug.h>
b0d623f7 A	43	#include <kern/thread.h>
b0d623f7 A	44
2d21ac55	45	extern int etext;
91447636 A	46	__BEGIN_DECLS
	47	// From osmfk/kern/thread.h but considered to be private
	48	extern vm_offset_t min_valid_stack_address(void);
	49	extern vm_offset_t max_valid_stack_address(void);
	50
	51	// From osfmk/kmod.c
	52	extern void kmod_dump_log(vm_offset_t *addr, unsigned int cnt);
0c530ab8 A	53
0c530ab8 A	54	extern addr64_t kvtophys(vm_offset_t va);
2d21ac55	55
91447636 A	56	__END_DECLS
91447636 A	57
b0d623f7 A	58	extern lck_grp_t *IOLockGroup;
	59
	60	static lck_mtx_t *sOSReportLock = lck_mtx_alloc_init(IOLockGroup, LCK_ATTR_NULL);
91447636	61
2d21ac55 A	62	/* Use kernel_debug() to log a backtrace */
2d21ac55 A	63	void
b0d623f7	64	trace_backtrace(uint32_t debugid, uint32_t debugid2, uintptr_t size, uintptr_t data) {
2d21ac55 A	65	void *bt[16];
	66	const unsigned cnt = sizeof(bt) / sizeof(bt[0]);
	67	unsigned i;
	68	int found = 0;
	69
	70	OSBacktrace(bt, cnt);
	71
	72	/* find first non-kernel frame */
	73	for (i = 3; i < cnt && bt[i]; i++) {
	74	if (bt[i] > (void*)&etext) {
	75	found = 1;
	76	break;
	77	}
	78	}
	79	/*
	80	* if there are non-kernel frames, only log these
	81	* otherwise, log everything but the first two
	82	*/
	83	if (!found) i=2;
	84
b0d623f7	85	#define safe_bt(a) (uintptr_t)(a<cnt ? bt[a] : 0)
2d21ac55 A	86	kernel_debug(debugid, data, size, safe_bt(i), safe_bt(i+1), 0);
	87	kernel_debug(debugid2, safe_bt(i+2), safe_bt(i+3), safe_bt(i+4), safe_bt(i+5), 0);
	88	}
	89
91447636 A	90	/* Report a message with a 4 entry backtrace - very slow */
	91	void
	92	OSReportWithBacktrace(const char *str, ...)
	93	{
	94	char buf[128];
	95	void *bt[9];
	96	const unsigned cnt = sizeof(bt) / sizeof(bt[0]);
	97	va_list listp;
	98
	99	// Ignore the our and our callers stackframes, skipping frames 0 & 1
	100	(void) OSBacktrace(bt, cnt);
	101
	102	va_start(listp, str);
	103	vsnprintf(buf, sizeof(buf), str, listp);
	104	va_end(listp);
	105
b0d623f7	106	lck_mtx_lock(sOSReportLock);
91447636	107	{
b0d623f7 A	108	printf("%s\nBacktrace %p %p %p %p %p %p %p\n",
	109	buf, bt[2], bt[3], bt[4], bt[5], bt[6], bt[7], bt[8]);
	110	kmod_dump_log((vm_offset_t *) &bt[2], cnt - 2);
91447636	111	}
b0d623f7	112	lck_mtx_unlock(sOSReportLock);
91447636 A	113	}
	114
	115	static vm_offset_t minstackaddr = min_valid_stack_address();
	116	static vm_offset_t maxstackaddr = max_valid_stack_address();
	117
0c530ab8 A	118	#if __i386__
	119	#define i386_RETURN_OFFSET 4
	120
	121	static unsigned int
	122	i386_validate_stackptr(vm_offset_t stackptr)
	123	{
	124	/* Existence and alignment check
	125	*/
	126	if (!stackptr \|\| (stackptr & 0x3))
	127	return 0;
	128
	129	/* Is a virtual->physical translation present?
	130	*/
	131	if (!kvtophys(stackptr))
	132	return 0;
	133
	134	/* Check if the return address lies on the same page;
	135	* If not, verify that a translation exists.
	136	*/
	137	if (((PAGE_SIZE - (stackptr & PAGE_MASK)) < i386_RETURN_OFFSET) &&
	138	!kvtophys(stackptr + i386_RETURN_OFFSET))
	139	return 0;
	140	return 1;
	141	}
	142
	143	static unsigned int
	144	i386_validate_raddr(vm_offset_t raddr)
	145	{
b0d623f7 A	146	return ((raddr > VM_MIN_KERNEL_AND_KEXT_ADDRESS) &&
	147	(raddr < VM_MAX_KERNEL_ADDRESS));
	148	}
	149	#endif
	150
	151	#if __x86_64__
	152	#define x86_64_RETURN_OFFSET 8
	153	static unsigned int
	154	x86_64_validate_raddr(vm_offset_t raddr)
	155	{
	156	return ((raddr > VM_MIN_KERNEL_AND_KEXT_ADDRESS) &&
0c530ab8 A	157	(raddr < VM_MAX_KERNEL_ADDRESS));
0c530ab8 A	158	}
b0d623f7 A	159	static unsigned int
	160	x86_64_validate_stackptr(vm_offset_t stackptr)
	161	{
	162	/* Existence and alignment check
	163	*/
	164	if (!stackptr \|\| (stackptr & 0x7) \|\| !x86_64_validate_raddr(stackptr))
	165	return 0;
	166
	167	/* Is a virtual->physical translation present?
	168	*/
	169	if (!kvtophys(stackptr))
	170	return 0;
	171
	172	/* Check if the return address lies on the same page;
	173	* If not, verify that a translation exists.
	174	*/
	175	if (((PAGE_SIZE - (stackptr & PAGE_MASK)) < x86_64_RETURN_OFFSET) &&
	176	!kvtophys(stackptr + x86_64_RETURN_OFFSET))
	177	return 0;
	178	return 1;
	179	}
0c530ab8 A	180	#endif
0c530ab8 A	181
b0d623f7	182
91447636 A	183	unsigned OSBacktrace(void **bt, unsigned maxAddrs)
	184	{
	185	unsigned frame;
	186
	187	#if __ppc__
	188	vm_offset_t stackptr, stackptr_prev;
	189	const vm_offset_t * const mem = (vm_offset_t *) 0;
	190	unsigned i = 0;
	191
	192	__asm__ volatile("mflr %0" : "=r" (stackptr));
	193	bt[i++] = (void *) stackptr;
	194
	195	__asm__ volatile("mr %0,r1" : "=r" (stackptr));
	196	for ( ; i < maxAddrs; i++) {
	197	// Validate we have a reasonable stackptr
	198	if ( !(minstackaddr <= stackptr && stackptr < maxstackaddr)
	199	\|\| (stackptr & 3))
	200	break;
	201
	202	stackptr_prev = stackptr;
	203	stackptr = mem[stackptr_prev >> 2];
b0d623f7	204	if ((stackptr - stackptr_prev) > 8 * 1024) // Sanity check
91447636 A	205	break;
	206
	207	vm_offset_t addr = mem[(stackptr >> 2) + 2];
	208	if ((addr & 3) \|\| (addr < 0x8000)) // More sanity checks
	209	break;
	210	bt[i] = (void *) addr;
	211	}
	212	frame = i;
	213
	214	for ( ; i < maxAddrs; i++)
	215	bt[i] = (void *) 0;
0c530ab8	216	#elif __i386__
b0d623f7	217	#define SANE_i386_FRAME_SIZE (kernel_stack_size >> 1)
0c530ab8 A	218	vm_offset_t stackptr, stackptr_prev, raddr;
	219	unsigned frame_index = 0;
	220	/* Obtain current frame pointer */
	221	__asm__ volatile("movl %%ebp, %0" : "=m" (stackptr));
4452a7af	222
0c530ab8 A	223	if (!i386_validate_stackptr(stackptr))
0c530ab8 A	224	goto pad;
4452a7af	225
0c530ab8 A	226	raddr = ((vm_offset_t ) (stackptr + i386_RETURN_OFFSET));
	227
	228	if (!i386_validate_raddr(raddr))
	229	goto pad;
	230
	231	bt[frame_index++] = (void *) raddr;
	232
	233	for ( ; frame_index < maxAddrs; frame_index++) {
	234	stackptr_prev = stackptr;
	235	stackptr = ((vm_offset_t ) stackptr_prev);
	236
	237	if (!i386_validate_stackptr(stackptr))
	238	break;
	239	/* Stack grows downwards */
	240	if (stackptr < stackptr_prev)
	241	break;
4452a7af	242
b0d623f7	243	if ((stackptr - stackptr_prev) > SANE_i386_FRAME_SIZE)
0c530ab8 A	244	break;
	245
	246	raddr = ((vm_offset_t ) (stackptr + i386_RETURN_OFFSET));
	247
	248	if (!i386_validate_raddr(raddr))
	249	break;
	250
	251	bt[frame_index] = (void *) raddr;
91447636	252	}
0c530ab8 A	253	pad:
0c530ab8 A	254	frame = frame_index;
91447636	255
b0d623f7 A	256	for ( ; frame_index < maxAddrs; frame_index++)
	257	bt[frame_index] = (void *) 0;
	258	#elif __x86_64__
	259	#define SANE_x86_64_FRAME_SIZE (kernel_stack_size >> 1)
	260	vm_offset_t stackptr, stackptr_prev, raddr;
	261	unsigned frame_index = 0;
	262	/* Obtain current frame pointer */
	263
	264	__asm__ volatile("movq %%rbp, %0" : "=m" (stackptr));
	265
	266	if (!x86_64_validate_stackptr(stackptr))
	267	goto pad;
	268
	269	raddr = ((vm_offset_t ) (stackptr + x86_64_RETURN_OFFSET));
	270
	271	if (!x86_64_validate_raddr(raddr))
	272	goto pad;
	273
	274	bt[frame_index++] = (void *) raddr;
	275
	276	for ( ; frame_index < maxAddrs; frame_index++) {
	277	stackptr_prev = stackptr;
	278	stackptr = ((vm_offset_t ) stackptr_prev);
	279
	280	if (!x86_64_validate_stackptr(stackptr))
	281	break;
	282	/* Stack grows downwards */
	283	if (stackptr < stackptr_prev)
	284	break;
	285
	286	if ((stackptr - stackptr_prev) > SANE_x86_64_FRAME_SIZE)
	287	break;
	288
	289	raddr = ((vm_offset_t ) (stackptr + x86_64_RETURN_OFFSET));
	290
	291	if (!x86_64_validate_raddr(raddr))
	292	break;
	293
	294	bt[frame_index] = (void *) raddr;
	295	}
	296	pad:
	297	frame = frame_index;
	298
0c530ab8 A	299	for ( ; frame_index < maxAddrs; frame_index++)
	300	bt[frame_index] = (void *) 0;
	301	#else
	302	#error arch
91447636	303	#endif
91447636 A	304	return frame;
91447636 A	305	}
b0d623f7	306