xnu-1699.22.73.tar.gz

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

diff --git a/libkern/gen/OSDebug.cpp b/libkern/gen/OSDebug.cpp
index f4c4d67605632e4cc1920ec9ec7227a3c946701e..3e67cfff8520f3732b668e7e840cd44f1ba8a2ee 100644 (file)
--- a/libkern/gen/OSDebug.cpp
+++ b/libkern/gen/OSDebug.cpp
@@ -28,16 +28,22 @@
 
 // NOTE:  This file is only c++ so I can get static initialisers going
 #include <libkern/OSDebug.h>
 
 // NOTE:  This file is only c++ so I can get static initialisers going
 #include <libkern/OSDebug.h>

+#include <IOKit/IOLib.h>

 
 #include <sys/cdefs.h>
 
 #include <stdarg.h>
 #include <mach/mach_types.h>
 #include <mach/kmod.h>
 
 #include <sys/cdefs.h>
 
 #include <stdarg.h>
 #include <mach/mach_types.h>
 #include <mach/kmod.h>

-#include <kern/lock.h>
+#include <kern/locks.h>

 
 #include <libkern/libkern.h>   // From bsd's libkern directory
 
 #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);
 __BEGIN_DECLS
 // From osmfk/kern/thread.h but considered to be private
 extern vm_offset_t min_valid_stack_address(void);


@@ -45,9 +51,42 @@ 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);
 
 // 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
 
 __END_DECLS
 

-static mutex_t *sOSReportLock = mutex_alloc(0);
+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
 
 /* Report a message with a 4 entry backtrace - very slow */
 void


@@ -65,112 +104,186 @@ OSReportWithBacktrace(const char *str, ...)
     vsnprintf(buf, sizeof(buf), str, listp);
     va_end(listp);
 
     vsnprintf(buf, sizeof(buf), str, listp);
     va_end(listp);
 

-    mutex_lock(sOSReportLock);
+    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);
+        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);

     }
     }

-    mutex_unlock(sOSReportLock);
+    lck_mtx_unlock(sOSReportLock);

 }
 
 static vm_offset_t minstackaddr = min_valid_stack_address();
 static vm_offset_t maxstackaddr = max_valid_stack_address();
 
 }
 
 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
+
+void
+OSPrintBacktrace(void)
+{
+       void * btbuf[20];
+       int tmp = OSBacktrace(btbuf, 20);
+       int i;
+       for(i=0;i<tmp;i++)
+       {
+               kprintf("bt[%.2d] = %p\n", i, btbuf[i]);
+       }
+}
+

 unsigned OSBacktrace(void **bt, unsigned maxAddrs)
 {
     unsigned frame;
 
 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_prev ^ stackptr) > 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 0 && __i386__    // Note that this should be ported for i386
-    // This function is not safe, we should get this code ported appropriately
-    if (maxAddrs > 16) {
-       for (frame = 16; frame < maxAddrs; frame++)
-           bt[frame] = __builtin_return_address(frame);
-       maxAddrs = 16;
-    }
+#if __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)); 

 
 

-    switch(maxAddrs) {
-    case 15+1: bt[15] = __builtin_return_address(15);
-    case 14+1: bt[14] = __builtin_return_address(14);
-    case 13+1: bt[13] = __builtin_return_address(13);
-    case 12+1: bt[12] = __builtin_return_address(12);
-    case 11+1: bt[11] = __builtin_return_address(11);
-    case 10+1: bt[10] = __builtin_return_address(10);
-    case  9+1: bt[ 9] = __builtin_return_address( 9);
-    case  8+1: bt[ 8] = __builtin_return_address( 8);
-    case  7+1: bt[ 7] = __builtin_return_address( 7);
-    case  6+1: bt[ 6] = __builtin_return_address( 6);
-    case  5+1: bt[ 5] = __builtin_return_address( 5);
-    case  4+1: bt[ 4] = __builtin_return_address( 4);
-    case  3+1: bt[ 3] = __builtin_return_address( 3);
-    case  2+1: bt[ 2] = __builtin_return_address( 2);
-    case  1+1: bt[ 1] = __builtin_return_address( 1);
-    case  0+1: bt[ 0] = __builtin_return_address( 0);
-    case 0: default: break;
-    }
+    if (!i386_validate_stackptr(stackptr))
+           goto pad;

 
 

-    frame = maxAddrs;
-#else
-    // This function is not safe, we should get this code ported appropriately
-    if (maxAddrs > 16) {
-       for (frame = 16; frame < maxAddrs; frame++)
-           bt[frame] = 0;
-       maxAddrs = 16;
+    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 */

 
 

-    switch (maxAddrs) {
-    case 15+1: bt[15] = __builtin_return_address(15);
-    case 14+1: bt[14] = __builtin_return_address(14);
-    case 13+1: bt[13] = __builtin_return_address(13);
-    case 12+1: bt[12] = __builtin_return_address(12);
-    case 11+1: bt[11] = __builtin_return_address(11);
-    case 10+1: bt[10] = __builtin_return_address(10);
-    case  9+1: bt[ 9] = __builtin_return_address( 9);
-    case  8+1: bt[ 8] = __builtin_return_address( 8);
-    case  7+1: bt[ 7] = __builtin_return_address( 7);
-    case  6+1: bt[ 6] = __builtin_return_address( 6);
-    case  5+1: bt[ 5] = __builtin_return_address( 5);
-    case  4+1: bt[ 4] = __builtin_return_address( 4);
-    case  3+1: bt[ 3] = __builtin_return_address( 3);
-    case  2+1: bt[ 2] = __builtin_return_address( 2);
-    case  1+1: bt[ 1] = __builtin_return_address( 1);
-    case  0+1: bt[ 0] = __builtin_return_address( 0);
-    case    0:
-    default  :
-       break;
+    __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;

 
 

-    frame = maxAddrs;
+    for ( ; frame_index < maxAddrs; frame_index++)
+           bt[frame_index] = (void *) 0;
+#else
+#error arch

 #endif
 #endif

-

     return frame;
 }
     return frame;
 }

+