xnu-6153.81.5.tar.gz

[apple/xnu.git] / osfmk / kern / stack.c

diff --git a/osfmk/kern/stack.c b/osfmk/kern/stack.c
index 400cedcf99491ea95e5dfdb2bbf0eaa54ce1147d..0481ddfdbf8f65681b257c07b408e90227abab68 100644 (file)
--- a/osfmk/kern/stack.c
+++ b/osfmk/kern/stack.c
@@ -1,8 +1,8 @@
 /*
 /*

- * Copyright (c) 2003-2007 Apple Inc. All rights reserved.
+ * Copyright (c) 2003-2019 Apple Inc. All rights reserved.

  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  *
  * @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
  * 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


@@ -11,10 +11,10 @@
  * 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.
  * 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.
  * 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,
  * 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,


@@ -22,7 +22,7 @@
  * 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.
  * 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@
  */
 /*
  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  */
 /*


@@ -34,6 +34,7 @@
 #include <mach/processor_set.h>
 
 #include <kern/kern_types.h>
 #include <mach/processor_set.h>
 
 #include <kern/kern_types.h>

+#include <kern/lock_group.h>

 #include <kern/mach_param.h>
 #include <kern/processor.h>
 #include <kern/thread.h>
 #include <kern/mach_param.h>
 #include <kern/processor.h>
 #include <kern/thread.h>


@@ -45,6 +46,7 @@
 #include <vm/vm_kern.h>
 
 #include <mach_debug.h>
 #include <vm/vm_kern.h>
 
 #include <mach_debug.h>

+#include <san/kasan.h>

 
 /*
  *     We allocate stacks from generic kernel VM.
 
 /*
  *     We allocate stacks from generic kernel VM.


@@ -53,101 +55,54 @@
  *     because stack_alloc_try/thread_invoke operate at splsched.
  */
 
  *     because stack_alloc_try/thread_invoke operate at splsched.
  */
 

-decl_simple_lock_data(static,stack_lock_data)
-#define stack_lock()           simple_lock(&stack_lock_data)
-#define stack_unlock()         simple_unlock(&stack_lock_data)
-
-#define STACK_CACHE_SIZE       2
-
-static vm_offset_t             stack_free_list;
-
-static unsigned int            stack_free_count, stack_free_hiwat;             /* free list count */
-static unsigned int            stack_hiwat;
-unsigned int                   stack_total;                            /* current total count */
-unsigned long long             stack_allocs;                           /* total count of allocations */
-
-static int                     stack_fake_zone_index = -1;     /* index in zone_info array */
-
-static unsigned int            stack_free_target;
-static int                             stack_free_delta;
-
-static unsigned int            stack_new_count;                                                /* total new stack allocations */
+decl_simple_lock_data(static, stack_lock_data);
+#define stack_lock()            simple_lock(&stack_lock_data, LCK_GRP_NULL)
+#define stack_unlock()          simple_unlock(&stack_lock_data)

 
 

-static vm_offset_t             stack_addr_mask;
+#define STACK_CACHE_SIZE        2

 
 

-unsigned int                   kernel_stack_pages;
-vm_offset_t                    kernel_stack_size;
-vm_offset_t                    kernel_stack_mask;
-vm_offset_t                    kernel_stack_depth_max;
+static vm_offset_t              stack_free_list;

 
 

-static inline void
-STACK_ZINFO_PALLOC(thread_t thread)
-{
-       task_t task;
-       zinfo_usage_t zinfo;
+static unsigned int             stack_free_count, stack_free_hiwat;             /* free list count */
+static unsigned int             stack_hiwat;
+unsigned int                    stack_total;                            /* current total count */
+unsigned long long              stack_allocs;                           /* total count of allocations */

 
 

-       ledger_credit(thread->t_ledger, task_ledgers.tkm_private, kernel_stack_size);
+static int                      stack_fake_zone_index = -1;     /* index in zone_info array */

 
 

-       if (stack_fake_zone_index != -1 &&
-           (task = thread->task) != NULL && (zinfo = task->tkm_zinfo) != NULL)
-               OSAddAtomic64(kernel_stack_size,
-                             (int64_t *)&zinfo[stack_fake_zone_index].alloc);
-}
+static unsigned int             stack_free_target;
+static int                              stack_free_delta;

 
 

-static inline void
-STACK_ZINFO_PFREE(thread_t thread)
-{
-       task_t task;
-       zinfo_usage_t zinfo;
+static unsigned int             stack_new_count;                                                /* total new stack allocations */

 
 

-       ledger_debit(thread->t_ledger, task_ledgers.tkm_private, kernel_stack_size);
-
-       if (stack_fake_zone_index != -1 &&
-           (task = thread->task) != NULL && (zinfo = task->tkm_zinfo) != NULL)
-               OSAddAtomic64(kernel_stack_size, 
-                             (int64_t *)&zinfo[stack_fake_zone_index].free);
-}
+static vm_offset_t              stack_addr_mask;

 
 

-static inline void
-STACK_ZINFO_HANDOFF(thread_t from, thread_t to)
-{
-       ledger_debit(from->t_ledger, task_ledgers.tkm_private, kernel_stack_size);
-       ledger_credit(to->t_ledger, task_ledgers.tkm_private, kernel_stack_size);
-
-       if (stack_fake_zone_index != -1) {
-               task_t task;
-               zinfo_usage_t zinfo;
-       
-               if ((task = from->task) != NULL && (zinfo = task->tkm_zinfo) != NULL)
-                       OSAddAtomic64(kernel_stack_size, 
-                                     (int64_t *)&zinfo[stack_fake_zone_index].free);
-
-               if ((task = to->task) != NULL && (zinfo = task->tkm_zinfo) != NULL)
-                       OSAddAtomic64(kernel_stack_size, 
-                                     (int64_t *)&zinfo[stack_fake_zone_index].alloc);
-       }
-}
+unsigned int                    kernel_stack_pages;
+vm_offset_t                     kernel_stack_size;
+vm_offset_t                     kernel_stack_mask;
+vm_offset_t                     kernel_stack_depth_max;

 
 /*
  *     The next field is at the base of the stack,
  *     so the low end is left unsullied.
  */
 
 /*
  *     The next field is at the base of the stack,
  *     so the low end is left unsullied.
  */

-#define stack_next(stack)      \
+#define stack_next(stack)       \

        (*((vm_offset_t *)((stack) + kernel_stack_size) - 1))
 
 static inline int
 log2(vm_offset_t size)
 {
        (*((vm_offset_t *)((stack) + kernel_stack_size) - 1))
 
 static inline int
 log2(vm_offset_t size)
 {

-       int     result;
-       for (result = 0; size > 0; result++)
+       int     result;
+       for (result = 0; size > 0; result++) {

                size >>= 1;
                size >>= 1;

+       }

        return result;
 }
 
 static inline vm_offset_t
 roundup_pow2(vm_offset_t size)
 {
        return result;
 }
 
 static inline vm_offset_t
 roundup_pow2(vm_offset_t size)
 {

-       return 1UL << (log2(size - 1) + 1); 
+       return 1UL << (log2(size - 1) + 1);

 }
 
 static vm_offset_t stack_alloc_internal(void);
 }
 
 static vm_offset_t stack_alloc_internal(void);


@@ -157,24 +112,25 @@ void
 stack_init(void)
 {
        simple_lock_init(&stack_lock_data, 0);
 stack_init(void)
 {
        simple_lock_init(&stack_lock_data, 0);

-       
+

        kernel_stack_pages = KERNEL_STACK_SIZE / PAGE_SIZE;
        kernel_stack_size = KERNEL_STACK_SIZE;
        kernel_stack_mask = -KERNEL_STACK_SIZE;
        kernel_stack_depth_max = 0;
 
        if (PE_parse_boot_argn("kernel_stack_pages",
        kernel_stack_pages = KERNEL_STACK_SIZE / PAGE_SIZE;
        kernel_stack_size = KERNEL_STACK_SIZE;
        kernel_stack_mask = -KERNEL_STACK_SIZE;
        kernel_stack_depth_max = 0;
 
        if (PE_parse_boot_argn("kernel_stack_pages",

-                              &kernel_stack_pages,
-                              sizeof (kernel_stack_pages))) {
+           &kernel_stack_pages,
+           sizeof(kernel_stack_pages))) {

                kernel_stack_size = kernel_stack_pages * PAGE_SIZE;
                printf("stack_init: kernel_stack_pages=%d kernel_stack_size=%p\n",
                kernel_stack_size = kernel_stack_pages * PAGE_SIZE;
                printf("stack_init: kernel_stack_pages=%d kernel_stack_size=%p\n",

-                       kernel_stack_pages, (void *) kernel_stack_size);
+                   kernel_stack_pages, (void *) kernel_stack_size);

        }
 
        }
 

-       if (kernel_stack_size < round_page(kernel_stack_size))
+       if (kernel_stack_size < round_page(kernel_stack_size)) {

                panic("stack_init: stack size %p not a multiple of page size %d\n",
                panic("stack_init: stack size %p not a multiple of page size %d\n",

-                       (void *) kernel_stack_size, PAGE_SIZE);
-       
+                   (void *) kernel_stack_size, PAGE_SIZE);
+       }
+

        stack_addr_mask = roundup_pow2(kernel_stack_size) - 1;
        kernel_stack_mask = ~stack_addr_mask;
 }
        stack_addr_mask = roundup_pow2(kernel_stack_size) - 1;
        kernel_stack_mask = ~stack_addr_mask;
 }


@@ -186,12 +142,13 @@ stack_init(void)
  *     block.
  */
 
  *     block.
  */
 

-static vm_offset_t 
+static vm_offset_t

 stack_alloc_internal(void)
 {
 stack_alloc_internal(void)
 {

-       vm_offset_t             stack;
-       spl_t                   s;
-       int                     guard_flags;
+       vm_offset_t             stack = 0;
+       spl_t                   s;
+       int                     flags = 0;
+       kern_return_t           kr = KERN_SUCCESS;

 
        s = splsched();
        stack_lock();
 
        s = splsched();
        stack_lock();


@@ -200,32 +157,32 @@ stack_alloc_internal(void)
        if (stack != 0) {
                stack_free_list = stack_next(stack);
                stack_free_count--;
        if (stack != 0) {
                stack_free_list = stack_next(stack);
                stack_free_count--;

-       }
-       else {
-               if (++stack_total > stack_hiwat)
+       } else {
+               if (++stack_total > stack_hiwat) {

                        stack_hiwat = stack_total;
                        stack_hiwat = stack_total;

+               }

                stack_new_count++;
        }
        stack_free_delta--;
        stack_unlock();
        splx(s);
                stack_new_count++;
        }
        stack_free_delta--;
        stack_unlock();
        splx(s);

-               
-       if (stack == 0) {

 
 

+       if (stack == 0) {

                /*
                 * Request guard pages on either side of the stack.  Ask
                 * kernel_memory_allocate() for two extra pages to account
                 * for these.
                 */
 
                /*
                 * Request guard pages on either side of the stack.  Ask
                 * kernel_memory_allocate() for two extra pages to account
                 * for these.
                 */
 

-               guard_flags = KMA_GUARD_FIRST | KMA_GUARD_LAST;
-               if (kernel_memory_allocate(kernel_map, &stack,
-                                          kernel_stack_size + (2*PAGE_SIZE),
-                                          stack_addr_mask,
-                                          KMA_KSTACK | KMA_KOBJECT | guard_flags,
-                                          VM_KERN_MEMORY_STACK)
-                   != KERN_SUCCESS)
-                       panic("stack_alloc: kernel_memory_allocate");
+               flags = KMA_GUARD_FIRST | KMA_GUARD_LAST | KMA_KSTACK | KMA_KOBJECT | KMA_ZERO;
+               kr = kernel_memory_allocate(kernel_map, &stack,
+                   kernel_stack_size + (2 * PAGE_SIZE),
+                   stack_addr_mask,
+                   flags,
+                   VM_KERN_MEMORY_STACK);
+               if (kr != KERN_SUCCESS) {
+                       panic("stack_alloc: kernel_memory_allocate(size:0x%llx, mask: 0x%llx, flags: 0x%x) failed with %d\n", (uint64_t)(kernel_stack_size + (2 * PAGE_SIZE)), (uint64_t)stack_addr_mask, flags, kr);
+               }

 
                /*
                 * The stack address that comes back is the address of the lower
 
                /*
                 * The stack address that comes back is the address of the lower


@@ -239,12 +196,10 @@ stack_alloc_internal(void)
 
 void
 stack_alloc(
 
 void
 stack_alloc(

-       thread_t        thread)
+       thread_t        thread)

 {
 {

-

        assert(thread->kernel_stack == 0);
        machine_stack_attach(thread, stack_alloc_internal());
        assert(thread->kernel_stack == 0);
        machine_stack_attach(thread, stack_alloc_internal());

-       STACK_ZINFO_PALLOC(thread);

 }
 
 void
 }
 
 void


@@ -252,7 +207,6 @@ stack_handoff(thread_t from, thread_t to)
 {
        assert(from == current_thread());
        machine_stack_handoff(from, to);
 {
        assert(from == current_thread());
        machine_stack_handoff(from, to);

-       STACK_ZINFO_HANDOFF(from, to);

 }
 
 /*
 }
 
 /*


@@ -262,33 +216,36 @@ stack_handoff(thread_t from, thread_t to)
  */
 void
 stack_free(
  */
 void
 stack_free(

-       thread_t        thread)
+       thread_t        thread)

 {
 {

-    vm_offset_t                stack = machine_stack_detach(thread);
+       vm_offset_t         stack = machine_stack_detach(thread);

 
        assert(stack);
        if (stack != thread->reserved_stack) {
 
        assert(stack);
        if (stack != thread->reserved_stack) {

-               STACK_ZINFO_PFREE(thread);

                stack_free_stack(stack);
        }
 }
 
 void
 stack_free_reserved(
                stack_free_stack(stack);
        }
 }
 
 void
 stack_free_reserved(

-       thread_t        thread)
+       thread_t        thread)

 {
        if (thread->reserved_stack != thread->kernel_stack) {
                stack_free_stack(thread->reserved_stack);
 {
        if (thread->reserved_stack != thread->kernel_stack) {
                stack_free_stack(thread->reserved_stack);

-               STACK_ZINFO_PFREE(thread);

        }
 }
 
 static void
 stack_free_stack(
        }
 }
 
 static void
 stack_free_stack(

-       vm_offset_t             stack)
+       vm_offset_t             stack)

 {
 {

-       struct stack_cache      *cache;
-       spl_t                           s;
+       struct stack_cache      *cache;
+       spl_t                           s;
+
+#if KASAN_DEBUG
+       /* Sanity check - stack should be unpoisoned by now */
+       assert(kasan_check_shadow(stack, kernel_stack_size, 0));
+#endif

 
        s = splsched();
        cache = &PROCESSOR_DATA(current_processor(), stack_cache);
 
        s = splsched();
        cache = &PROCESSOR_DATA(current_processor(), stack_cache);


@@ -296,13 +253,13 @@ stack_free_stack(
                stack_next(stack) = cache->free;
                cache->free = stack;
                cache->count++;
                stack_next(stack) = cache->free;
                cache->free = stack;
                cache->count++;

-       }
-       else {
+       } else {

                stack_lock();
                stack_next(stack) = stack_free_list;
                stack_free_list = stack;
                stack_lock();
                stack_next(stack) = stack_free_list;
                stack_free_list = stack;

-               if (++stack_free_count > stack_free_hiwat)
+               if (++stack_free_count > stack_free_hiwat) {

                        stack_free_hiwat = stack_free_count;
                        stack_free_hiwat = stack_free_count;

+               }

                stack_free_delta++;
                stack_unlock();
        }
                stack_free_delta++;
                stack_unlock();
        }


@@ -321,24 +278,21 @@ stack_free_stack(
  */
 boolean_t
 stack_alloc_try(
  */
 boolean_t
 stack_alloc_try(

-       thread_t                thread)
+       thread_t                thread)

 {
 {

-       struct stack_cache      *cache;
-       vm_offset_t                     stack;
+       struct stack_cache      *cache;
+       vm_offset_t                     stack;

 
        cache = &PROCESSOR_DATA(current_processor(), stack_cache);
        stack = cache->free;
        if (stack != 0) {
 
        cache = &PROCESSOR_DATA(current_processor(), stack_cache);
        stack = cache->free;
        if (stack != 0) {

-               STACK_ZINFO_PALLOC(thread);

                cache->free = stack_next(stack);
                cache->count--;
                cache->free = stack_next(stack);
                cache->count--;

-       }
-       else {
+       } else {

                if (stack_free_list != 0) {
                        stack_lock();
                        stack = stack_free_list;
                        if (stack != 0) {
                if (stack_free_list != 0) {
                        stack_lock();
                        stack = stack_free_list;
                        if (stack != 0) {

-                               STACK_ZINFO_PALLOC(thread);

                                stack_free_list = stack_next(stack);
                                stack_free_count--;
                                stack_free_delta--;
                                stack_free_list = stack_next(stack);
                                stack_free_count--;
                                stack_free_delta--;


@@ -349,13 +303,13 @@ stack_alloc_try(
 
        if (stack != 0 || (stack = thread->reserved_stack) != 0) {
                machine_stack_attach(thread, stack);
 
        if (stack != 0 || (stack = thread->reserved_stack) != 0) {
                machine_stack_attach(thread, stack);

-               return (TRUE);
+               return TRUE;

        }
 
        }
 

-       return (FALSE);
+       return FALSE;

 }
 
 }
 

-static unsigned int            stack_collect_tick, last_stack_tick;
+static unsigned int             stack_collect_tick, last_stack_tick;

 
 /*
  *     stack_collect:
 
 /*
  *     stack_collect:


@@ -367,9 +321,9 @@ void
 stack_collect(void)
 {
        if (stack_collect_tick != last_stack_tick) {
 stack_collect(void)
 {
        if (stack_collect_tick != last_stack_tick) {

-               unsigned int    target;
-               vm_offset_t             stack;
-               spl_t                   s;
+               unsigned int    target;
+               vm_offset_t             stack;
+               spl_t                   s;

 
                s = splsched();
                stack_lock();
 
                s = splsched();
                stack_lock();


@@ -399,10 +353,11 @@ stack_collect(void)
                        if (vm_map_remove(
                                    kernel_map,
                                    stack,
                        if (vm_map_remove(
                                    kernel_map,
                                    stack,

-                                   stack + kernel_stack_size+(2*PAGE_SIZE),
+                                   stack + kernel_stack_size + (2 * PAGE_SIZE),

                                    VM_MAP_REMOVE_KUNWIRE)
                                    VM_MAP_REMOVE_KUNWIRE)

-                           != KERN_SUCCESS)
+                           != KERN_SUCCESS) {

                                panic("stack_collect: vm_map_remove");
                                panic("stack_collect: vm_map_remove");

+                       }

                        stack = 0;
 
                        s = splsched();
                        stack = 0;
 
                        s = splsched();


@@ -430,18 +385,18 @@ stack_collect(void)
  */
 void
 compute_stack_target(
  */
 void
 compute_stack_target(

-__unused void          *arg)
+       __unused void           *arg)

 {
 {

-       spl_t           s;
+       spl_t           s;

 
        s = splsched();
        stack_lock();
 
 
        s = splsched();
        stack_lock();
 

-       if (stack_free_target > 5)
+       if (stack_free_target > 5) {

                stack_free_target = (4 * stack_free_target) / 5;
                stack_free_target = (4 * stack_free_target) / 5;

-       else
-       if (stack_free_target > 0)
+       } else if (stack_free_target > 0) {

                stack_free_target--;
                stack_free_target--;

+       }

 
        stack_free_target += (stack_free_delta >= 0)? stack_free_delta: -stack_free_delta;
 
 
        stack_free_target += (stack_free_delta >= 0)? stack_free_delta: -stack_free_delta;
 


@@ -459,13 +414,13 @@ stack_fake_zone_init(int zone_index)
 }
 
 void
 }
 
 void

-stack_fake_zone_info(int *count, 
-                    vm_size_t *cur_size, vm_size_t *max_size, vm_size_t *elem_size, vm_size_t *alloc_size,
-                    uint64_t *sum_size, int *collectable, int *exhaustable, int *caller_acct)
+stack_fake_zone_info(int *count,
+    vm_size_t *cur_size, vm_size_t *max_size, vm_size_t *elem_size, vm_size_t *alloc_size,
+    uint64_t *sum_size, int *collectable, int *exhaustable, int *caller_acct)

 {
 {

-       unsigned int    total, hiwat, free;
+       unsigned int    total, hiwat, free;

        unsigned long long all;
        unsigned long long all;

-       spl_t                   s;
+       spl_t                   s;

 
        s = splsched();
        stack_lock();
 
        s = splsched();
        stack_lock();


@@ -489,12 +444,12 @@ stack_fake_zone_info(int *count,
 }
 
 /* OBSOLETE */
 }
 
 /* OBSOLETE */

-void   stack_privilege(
-                       thread_t        thread);
+void    stack_privilege(
+       thread_t        thread);

 
 void
 stack_privilege(
 
 void
 stack_privilege(

-       __unused thread_t       thread)
+       __unused thread_t       thread)

 {
        /* OBSOLETE */
 }
 {
        /* OBSOLETE */
 }


@@ -504,31 +459,32 @@ stack_privilege(
  */
 kern_return_t
 processor_set_stack_usage(
  */
 kern_return_t
 processor_set_stack_usage(

-       processor_set_t pset,
-       unsigned int    *totalp,
-       vm_size_t       *spacep,
-       vm_size_t       *residentp,
-       vm_size_t       *maxusagep,
-       vm_offset_t     *maxstackp)
+       processor_set_t pset,
+       unsigned int    *totalp,
+       vm_size_t       *spacep,
+       vm_size_t       *residentp,
+       vm_size_t       *maxusagep,
+       vm_offset_t     *maxstackp)

 {
 #if !MACH_DEBUG
 {
 #if !MACH_DEBUG

-        return KERN_NOT_SUPPORTED;
+       return KERN_NOT_SUPPORTED;

 #else
        unsigned int total;
        vm_size_t maxusage;
        vm_offset_t maxstack;
 
 #else
        unsigned int total;
        vm_size_t maxusage;
        vm_offset_t maxstack;
 

-       register thread_t *thread_list;
-       register thread_t thread;
+       thread_t *thread_list;
+       thread_t thread;

 
 

-       unsigned int actual;    /* this many things */
+       unsigned int actual;    /* this many things */

        unsigned int i;
 
        vm_size_t size, size_needed;
        void *addr;
 
        unsigned int i;
 
        vm_size_t size, size_needed;
        void *addr;
 

-       if (pset == PROCESSOR_SET_NULL || pset != &pset0)
+       if (pset == PROCESSOR_SET_NULL || pset != &pset0) {

                return KERN_INVALID_ARGUMENT;
                return KERN_INVALID_ARGUMENT;

+       }

 
        size = 0;
        addr = NULL;
 
        size = 0;
        addr = NULL;


@@ -541,27 +497,30 @@ processor_set_stack_usage(
                /* do we have the memory we need? */
 
                size_needed = actual * sizeof(thread_t);
                /* do we have the memory we need? */
 
                size_needed = actual * sizeof(thread_t);

-               if (size_needed <= size)
+               if (size_needed <= size) {

                        break;
                        break;

+               }

 
                lck_mtx_unlock(&tasks_threads_lock);
 
 
                lck_mtx_unlock(&tasks_threads_lock);
 

-               if (size != 0)
+               if (size != 0) {

                        kfree(addr, size);
                        kfree(addr, size);

+               }

 
                assert(size_needed > 0);
                size = size_needed;
 
                addr = kalloc(size);
 
                assert(size_needed > 0);
                size = size_needed;
 
                addr = kalloc(size);

-               if (addr == 0)
+               if (addr == 0) {

                        return KERN_RESOURCE_SHORTAGE;
                        return KERN_RESOURCE_SHORTAGE;

+               }

        }
 
        /* OK, have memory and list is locked */
        thread_list = (thread_t *) addr;
        for (i = 0, thread = (thread_t)(void *) queue_first(&threads);
        }
 
        /* OK, have memory and list is locked */
        thread_list = (thread_t *) addr;
        for (i = 0, thread = (thread_t)(void *) queue_first(&threads);

-                                       !queue_end(&threads, (queue_entry_t) thread);
-                                       thread = (thread_t)(void *) queue_next(&thread->threads)) {
+           !queue_end(&threads, (queue_entry_t) thread);
+           thread = (thread_t)(void *) queue_next(&thread->threads)) {

                thread_reference_internal(thread);
                thread_list[i++] = thread;
        }
                thread_reference_internal(thread);
                thread_list[i++] = thread;
        }


@@ -577,14 +536,16 @@ processor_set_stack_usage(
        while (i > 0) {
                thread_t threadref = thread_list[--i];
 
        while (i > 0) {
                thread_t threadref = thread_list[--i];
 

-               if (threadref->kernel_stack != 0)
+               if (threadref->kernel_stack != 0) {

                        total++;
                        total++;

+               }

 
                thread_deallocate(threadref);
        }
 
 
                thread_deallocate(threadref);
        }
 

-       if (size != 0)
+       if (size != 0) {

                kfree(addr, size);
                kfree(addr, size);

+       }

 
        *totalp = total;
        *residentp = *spacep = total * round_page(kernel_stack_size);
 
        *totalp = total;
        *residentp = *spacep = total * round_page(kernel_stack_size);


@@ -592,15 +553,17 @@ processor_set_stack_usage(
        *maxstackp = maxstack;
        return KERN_SUCCESS;
 
        *maxstackp = maxstack;
        return KERN_SUCCESS;
 

-#endif /* MACH_DEBUG */
+#endif  /* MACH_DEBUG */

 }
 
 }
 

-vm_offset_t min_valid_stack_address(void)
+vm_offset_t
+min_valid_stack_address(void)

 {
        return (vm_offset_t)vm_map_min(kernel_map);
 }
 
 {
        return (vm_offset_t)vm_map_min(kernel_map);
 }
 

-vm_offset_t max_valid_stack_address(void)
+vm_offset_t
+max_valid_stack_address(void)

 {
        return (vm_offset_t)vm_map_max(kernel_map);
 }
 {
        return (vm_offset_t)vm_map_max(kernel_map);
 }