target/user: Add an #include directive
[linux/fpc-iii.git] / mm / kasan / kasan.c
blob0e9505f66ec133bd401d6ec9208d1a6f17b95fb7
1 /*
2 * This file contains shadow memory manipulation code.
4 * Copyright (c) 2014 Samsung Electronics Co., Ltd.
5 * Author: Andrey Ryabinin <ryabinin.a.a@gmail.com>
7 * Some code borrowed from https://github.com/xairy/kasan-prototype by
8 * Andrey Konovalov <adech.fo@gmail.com>
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
16 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
17 #define DISABLE_BRANCH_PROFILING
19 #include <linux/export.h>
20 #include <linux/interrupt.h>
21 #include <linux/init.h>
22 #include <linux/kasan.h>
23 #include <linux/kernel.h>
24 #include <linux/kmemleak.h>
25 #include <linux/linkage.h>
26 #include <linux/memblock.h>
27 #include <linux/memory.h>
28 #include <linux/mm.h>
29 #include <linux/module.h>
30 #include <linux/printk.h>
31 #include <linux/sched.h>
32 #include <linux/slab.h>
33 #include <linux/stacktrace.h>
34 #include <linux/string.h>
35 #include <linux/types.h>
36 #include <linux/vmalloc.h>
37 #include <linux/bug.h>
39 #include "kasan.h"
40 #include "../slab.h"
43 * Poisons the shadow memory for 'size' bytes starting from 'addr'.
44 * Memory addresses should be aligned to KASAN_SHADOW_SCALE_SIZE.
46 static void kasan_poison_shadow(const void *address, size_t size, u8 value)
48 void *shadow_start, *shadow_end;
50 shadow_start = kasan_mem_to_shadow(address);
51 shadow_end = kasan_mem_to_shadow(address + size);
53 memset(shadow_start, value, shadow_end - shadow_start);
56 void kasan_unpoison_shadow(const void *address, size_t size)
58 kasan_poison_shadow(address, size, 0);
60 if (size & KASAN_SHADOW_MASK) {
61 u8 *shadow = (u8 *)kasan_mem_to_shadow(address + size);
62 *shadow = size & KASAN_SHADOW_MASK;
66 static void __kasan_unpoison_stack(struct task_struct *task, const void *sp)
68 void *base = task_stack_page(task);
69 size_t size = sp - base;
71 kasan_unpoison_shadow(base, size);
74 /* Unpoison the entire stack for a task. */
75 void kasan_unpoison_task_stack(struct task_struct *task)
77 __kasan_unpoison_stack(task, task_stack_page(task) + THREAD_SIZE);
80 /* Unpoison the stack for the current task beyond a watermark sp value. */
81 asmlinkage void kasan_unpoison_task_stack_below(const void *watermark)
83 __kasan_unpoison_stack(current, watermark);
87 * Clear all poison for the region between the current SP and a provided
88 * watermark value, as is sometimes required prior to hand-crafted asm function
89 * returns in the middle of functions.
91 void kasan_unpoison_stack_above_sp_to(const void *watermark)
93 const void *sp = __builtin_frame_address(0);
94 size_t size = watermark - sp;
96 if (WARN_ON(sp > watermark))
97 return;
98 kasan_unpoison_shadow(sp, size);
102 * All functions below always inlined so compiler could
103 * perform better optimizations in each of __asan_loadX/__assn_storeX
104 * depending on memory access size X.
107 static __always_inline bool memory_is_poisoned_1(unsigned long addr)
109 s8 shadow_value = *(s8 *)kasan_mem_to_shadow((void *)addr);
111 if (unlikely(shadow_value)) {
112 s8 last_accessible_byte = addr & KASAN_SHADOW_MASK;
113 return unlikely(last_accessible_byte >= shadow_value);
116 return false;
119 static __always_inline bool memory_is_poisoned_2(unsigned long addr)
121 u16 *shadow_addr = (u16 *)kasan_mem_to_shadow((void *)addr);
123 if (unlikely(*shadow_addr)) {
124 if (memory_is_poisoned_1(addr + 1))
125 return true;
128 * If single shadow byte covers 2-byte access, we don't
129 * need to do anything more. Otherwise, test the first
130 * shadow byte.
132 if (likely(((addr + 1) & KASAN_SHADOW_MASK) != 0))
133 return false;
135 return unlikely(*(u8 *)shadow_addr);
138 return false;
141 static __always_inline bool memory_is_poisoned_4(unsigned long addr)
143 u16 *shadow_addr = (u16 *)kasan_mem_to_shadow((void *)addr);
145 if (unlikely(*shadow_addr)) {
146 if (memory_is_poisoned_1(addr + 3))
147 return true;
150 * If single shadow byte covers 4-byte access, we don't
151 * need to do anything more. Otherwise, test the first
152 * shadow byte.
154 if (likely(((addr + 3) & KASAN_SHADOW_MASK) >= 3))
155 return false;
157 return unlikely(*(u8 *)shadow_addr);
160 return false;
163 static __always_inline bool memory_is_poisoned_8(unsigned long addr)
165 u16 *shadow_addr = (u16 *)kasan_mem_to_shadow((void *)addr);
167 if (unlikely(*shadow_addr)) {
168 if (memory_is_poisoned_1(addr + 7))
169 return true;
172 * If single shadow byte covers 8-byte access, we don't
173 * need to do anything more. Otherwise, test the first
174 * shadow byte.
176 if (likely(IS_ALIGNED(addr, KASAN_SHADOW_SCALE_SIZE)))
177 return false;
179 return unlikely(*(u8 *)shadow_addr);
182 return false;
185 static __always_inline bool memory_is_poisoned_16(unsigned long addr)
187 u32 *shadow_addr = (u32 *)kasan_mem_to_shadow((void *)addr);
189 if (unlikely(*shadow_addr)) {
190 u16 shadow_first_bytes = *(u16 *)shadow_addr;
192 if (unlikely(shadow_first_bytes))
193 return true;
196 * If two shadow bytes covers 16-byte access, we don't
197 * need to do anything more. Otherwise, test the last
198 * shadow byte.
200 if (likely(IS_ALIGNED(addr, KASAN_SHADOW_SCALE_SIZE)))
201 return false;
203 return memory_is_poisoned_1(addr + 15);
206 return false;
209 static __always_inline unsigned long bytes_is_zero(const u8 *start,
210 size_t size)
212 while (size) {
213 if (unlikely(*start))
214 return (unsigned long)start;
215 start++;
216 size--;
219 return 0;
222 static __always_inline unsigned long memory_is_zero(const void *start,
223 const void *end)
225 unsigned int words;
226 unsigned long ret;
227 unsigned int prefix = (unsigned long)start % 8;
229 if (end - start <= 16)
230 return bytes_is_zero(start, end - start);
232 if (prefix) {
233 prefix = 8 - prefix;
234 ret = bytes_is_zero(start, prefix);
235 if (unlikely(ret))
236 return ret;
237 start += prefix;
240 words = (end - start) / 8;
241 while (words) {
242 if (unlikely(*(u64 *)start))
243 return bytes_is_zero(start, 8);
244 start += 8;
245 words--;
248 return bytes_is_zero(start, (end - start) % 8);
251 static __always_inline bool memory_is_poisoned_n(unsigned long addr,
252 size_t size)
254 unsigned long ret;
256 ret = memory_is_zero(kasan_mem_to_shadow((void *)addr),
257 kasan_mem_to_shadow((void *)addr + size - 1) + 1);
259 if (unlikely(ret)) {
260 unsigned long last_byte = addr + size - 1;
261 s8 *last_shadow = (s8 *)kasan_mem_to_shadow((void *)last_byte);
263 if (unlikely(ret != (unsigned long)last_shadow ||
264 ((long)(last_byte & KASAN_SHADOW_MASK) >= *last_shadow)))
265 return true;
267 return false;
270 static __always_inline bool memory_is_poisoned(unsigned long addr, size_t size)
272 if (__builtin_constant_p(size)) {
273 switch (size) {
274 case 1:
275 return memory_is_poisoned_1(addr);
276 case 2:
277 return memory_is_poisoned_2(addr);
278 case 4:
279 return memory_is_poisoned_4(addr);
280 case 8:
281 return memory_is_poisoned_8(addr);
282 case 16:
283 return memory_is_poisoned_16(addr);
284 default:
285 BUILD_BUG();
289 return memory_is_poisoned_n(addr, size);
292 static __always_inline void check_memory_region_inline(unsigned long addr,
293 size_t size, bool write,
294 unsigned long ret_ip)
296 if (unlikely(size == 0))
297 return;
299 if (unlikely((void *)addr <
300 kasan_shadow_to_mem((void *)KASAN_SHADOW_START))) {
301 kasan_report(addr, size, write, ret_ip);
302 return;
305 if (likely(!memory_is_poisoned(addr, size)))
306 return;
308 kasan_report(addr, size, write, ret_ip);
311 static void check_memory_region(unsigned long addr,
312 size_t size, bool write,
313 unsigned long ret_ip)
315 check_memory_region_inline(addr, size, write, ret_ip);
318 void kasan_check_read(const void *p, unsigned int size)
320 check_memory_region((unsigned long)p, size, false, _RET_IP_);
322 EXPORT_SYMBOL(kasan_check_read);
324 void kasan_check_write(const void *p, unsigned int size)
326 check_memory_region((unsigned long)p, size, true, _RET_IP_);
328 EXPORT_SYMBOL(kasan_check_write);
330 #undef memset
331 void *memset(void *addr, int c, size_t len)
333 check_memory_region((unsigned long)addr, len, true, _RET_IP_);
335 return __memset(addr, c, len);
338 #undef memmove
339 void *memmove(void *dest, const void *src, size_t len)
341 check_memory_region((unsigned long)src, len, false, _RET_IP_);
342 check_memory_region((unsigned long)dest, len, true, _RET_IP_);
344 return __memmove(dest, src, len);
347 #undef memcpy
348 void *memcpy(void *dest, const void *src, size_t len)
350 check_memory_region((unsigned long)src, len, false, _RET_IP_);
351 check_memory_region((unsigned long)dest, len, true, _RET_IP_);
353 return __memcpy(dest, src, len);
356 void kasan_alloc_pages(struct page *page, unsigned int order)
358 if (likely(!PageHighMem(page)))
359 kasan_unpoison_shadow(page_address(page), PAGE_SIZE << order);
362 void kasan_free_pages(struct page *page, unsigned int order)
364 if (likely(!PageHighMem(page)))
365 kasan_poison_shadow(page_address(page),
366 PAGE_SIZE << order,
367 KASAN_FREE_PAGE);
371 * Adaptive redzone policy taken from the userspace AddressSanitizer runtime.
372 * For larger allocations larger redzones are used.
374 static size_t optimal_redzone(size_t object_size)
376 int rz =
377 object_size <= 64 - 16 ? 16 :
378 object_size <= 128 - 32 ? 32 :
379 object_size <= 512 - 64 ? 64 :
380 object_size <= 4096 - 128 ? 128 :
381 object_size <= (1 << 14) - 256 ? 256 :
382 object_size <= (1 << 15) - 512 ? 512 :
383 object_size <= (1 << 16) - 1024 ? 1024 : 2048;
384 return rz;
387 void kasan_cache_create(struct kmem_cache *cache, size_t *size,
388 unsigned long *flags)
390 int redzone_adjust;
391 int orig_size = *size;
393 /* Add alloc meta. */
394 cache->kasan_info.alloc_meta_offset = *size;
395 *size += sizeof(struct kasan_alloc_meta);
397 /* Add free meta. */
398 if (cache->flags & SLAB_DESTROY_BY_RCU || cache->ctor ||
399 cache->object_size < sizeof(struct kasan_free_meta)) {
400 cache->kasan_info.free_meta_offset = *size;
401 *size += sizeof(struct kasan_free_meta);
403 redzone_adjust = optimal_redzone(cache->object_size) -
404 (*size - cache->object_size);
406 if (redzone_adjust > 0)
407 *size += redzone_adjust;
409 *size = min(KMALLOC_MAX_SIZE, max(*size, cache->object_size +
410 optimal_redzone(cache->object_size)));
413 * If the metadata doesn't fit, don't enable KASAN at all.
415 if (*size <= cache->kasan_info.alloc_meta_offset ||
416 *size <= cache->kasan_info.free_meta_offset) {
417 cache->kasan_info.alloc_meta_offset = 0;
418 cache->kasan_info.free_meta_offset = 0;
419 *size = orig_size;
420 return;
423 *flags |= SLAB_KASAN;
426 void kasan_cache_shrink(struct kmem_cache *cache)
428 quarantine_remove_cache(cache);
431 void kasan_cache_destroy(struct kmem_cache *cache)
433 quarantine_remove_cache(cache);
436 size_t kasan_metadata_size(struct kmem_cache *cache)
438 return (cache->kasan_info.alloc_meta_offset ?
439 sizeof(struct kasan_alloc_meta) : 0) +
440 (cache->kasan_info.free_meta_offset ?
441 sizeof(struct kasan_free_meta) : 0);
444 void kasan_poison_slab(struct page *page)
446 kasan_poison_shadow(page_address(page),
447 PAGE_SIZE << compound_order(page),
448 KASAN_KMALLOC_REDZONE);
451 void kasan_unpoison_object_data(struct kmem_cache *cache, void *object)
453 kasan_unpoison_shadow(object, cache->object_size);
456 void kasan_poison_object_data(struct kmem_cache *cache, void *object)
458 kasan_poison_shadow(object,
459 round_up(cache->object_size, KASAN_SHADOW_SCALE_SIZE),
460 KASAN_KMALLOC_REDZONE);
463 static inline int in_irqentry_text(unsigned long ptr)
465 return (ptr >= (unsigned long)&__irqentry_text_start &&
466 ptr < (unsigned long)&__irqentry_text_end) ||
467 (ptr >= (unsigned long)&__softirqentry_text_start &&
468 ptr < (unsigned long)&__softirqentry_text_end);
471 static inline void filter_irq_stacks(struct stack_trace *trace)
473 int i;
475 if (!trace->nr_entries)
476 return;
477 for (i = 0; i < trace->nr_entries; i++)
478 if (in_irqentry_text(trace->entries[i])) {
479 /* Include the irqentry function into the stack. */
480 trace->nr_entries = i + 1;
481 break;
485 static inline depot_stack_handle_t save_stack(gfp_t flags)
487 unsigned long entries[KASAN_STACK_DEPTH];
488 struct stack_trace trace = {
489 .nr_entries = 0,
490 .entries = entries,
491 .max_entries = KASAN_STACK_DEPTH,
492 .skip = 0
495 save_stack_trace(&trace);
496 filter_irq_stacks(&trace);
497 if (trace.nr_entries != 0 &&
498 trace.entries[trace.nr_entries-1] == ULONG_MAX)
499 trace.nr_entries--;
501 return depot_save_stack(&trace, flags);
504 static inline void set_track(struct kasan_track *track, gfp_t flags)
506 track->pid = current->pid;
507 track->stack = save_stack(flags);
510 struct kasan_alloc_meta *get_alloc_info(struct kmem_cache *cache,
511 const void *object)
513 BUILD_BUG_ON(sizeof(struct kasan_alloc_meta) > 32);
514 return (void *)object + cache->kasan_info.alloc_meta_offset;
517 struct kasan_free_meta *get_free_info(struct kmem_cache *cache,
518 const void *object)
520 BUILD_BUG_ON(sizeof(struct kasan_free_meta) > 32);
521 return (void *)object + cache->kasan_info.free_meta_offset;
524 void kasan_init_slab_obj(struct kmem_cache *cache, const void *object)
526 struct kasan_alloc_meta *alloc_info;
528 if (!(cache->flags & SLAB_KASAN))
529 return;
531 alloc_info = get_alloc_info(cache, object);
532 __memset(alloc_info, 0, sizeof(*alloc_info));
535 void kasan_slab_alloc(struct kmem_cache *cache, void *object, gfp_t flags)
537 kasan_kmalloc(cache, object, cache->object_size, flags);
540 static void kasan_poison_slab_free(struct kmem_cache *cache, void *object)
542 unsigned long size = cache->object_size;
543 unsigned long rounded_up_size = round_up(size, KASAN_SHADOW_SCALE_SIZE);
545 /* RCU slabs could be legally used after free within the RCU period */
546 if (unlikely(cache->flags & SLAB_DESTROY_BY_RCU))
547 return;
549 kasan_poison_shadow(object, rounded_up_size, KASAN_KMALLOC_FREE);
552 bool kasan_slab_free(struct kmem_cache *cache, void *object)
554 s8 shadow_byte;
556 /* RCU slabs could be legally used after free within the RCU period */
557 if (unlikely(cache->flags & SLAB_DESTROY_BY_RCU))
558 return false;
560 shadow_byte = READ_ONCE(*(s8 *)kasan_mem_to_shadow(object));
561 if (shadow_byte < 0 || shadow_byte >= KASAN_SHADOW_SCALE_SIZE) {
562 kasan_report_double_free(cache, object, shadow_byte);
563 return true;
566 kasan_poison_slab_free(cache, object);
568 if (unlikely(!(cache->flags & SLAB_KASAN)))
569 return false;
571 set_track(&get_alloc_info(cache, object)->free_track, GFP_NOWAIT);
572 quarantine_put(get_free_info(cache, object), cache);
573 return true;
576 void kasan_kmalloc(struct kmem_cache *cache, const void *object, size_t size,
577 gfp_t flags)
579 unsigned long redzone_start;
580 unsigned long redzone_end;
582 if (gfpflags_allow_blocking(flags))
583 quarantine_reduce();
585 if (unlikely(object == NULL))
586 return;
588 redzone_start = round_up((unsigned long)(object + size),
589 KASAN_SHADOW_SCALE_SIZE);
590 redzone_end = round_up((unsigned long)object + cache->object_size,
591 KASAN_SHADOW_SCALE_SIZE);
593 kasan_unpoison_shadow(object, size);
594 kasan_poison_shadow((void *)redzone_start, redzone_end - redzone_start,
595 KASAN_KMALLOC_REDZONE);
597 if (cache->flags & SLAB_KASAN)
598 set_track(&get_alloc_info(cache, object)->alloc_track, flags);
600 EXPORT_SYMBOL(kasan_kmalloc);
602 void kasan_kmalloc_large(const void *ptr, size_t size, gfp_t flags)
604 struct page *page;
605 unsigned long redzone_start;
606 unsigned long redzone_end;
608 if (gfpflags_allow_blocking(flags))
609 quarantine_reduce();
611 if (unlikely(ptr == NULL))
612 return;
614 page = virt_to_page(ptr);
615 redzone_start = round_up((unsigned long)(ptr + size),
616 KASAN_SHADOW_SCALE_SIZE);
617 redzone_end = (unsigned long)ptr + (PAGE_SIZE << compound_order(page));
619 kasan_unpoison_shadow(ptr, size);
620 kasan_poison_shadow((void *)redzone_start, redzone_end - redzone_start,
621 KASAN_PAGE_REDZONE);
624 void kasan_krealloc(const void *object, size_t size, gfp_t flags)
626 struct page *page;
628 if (unlikely(object == ZERO_SIZE_PTR))
629 return;
631 page = virt_to_head_page(object);
633 if (unlikely(!PageSlab(page)))
634 kasan_kmalloc_large(object, size, flags);
635 else
636 kasan_kmalloc(page->slab_cache, object, size, flags);
639 void kasan_poison_kfree(void *ptr)
641 struct page *page;
643 page = virt_to_head_page(ptr);
645 if (unlikely(!PageSlab(page)))
646 kasan_poison_shadow(ptr, PAGE_SIZE << compound_order(page),
647 KASAN_FREE_PAGE);
648 else
649 kasan_poison_slab_free(page->slab_cache, ptr);
652 void kasan_kfree_large(const void *ptr)
654 struct page *page = virt_to_page(ptr);
656 kasan_poison_shadow(ptr, PAGE_SIZE << compound_order(page),
657 KASAN_FREE_PAGE);
660 int kasan_module_alloc(void *addr, size_t size)
662 void *ret;
663 size_t shadow_size;
664 unsigned long shadow_start;
666 shadow_start = (unsigned long)kasan_mem_to_shadow(addr);
667 shadow_size = round_up(size >> KASAN_SHADOW_SCALE_SHIFT,
668 PAGE_SIZE);
670 if (WARN_ON(!PAGE_ALIGNED(shadow_start)))
671 return -EINVAL;
673 ret = __vmalloc_node_range(shadow_size, 1, shadow_start,
674 shadow_start + shadow_size,
675 GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO,
676 PAGE_KERNEL, VM_NO_GUARD, NUMA_NO_NODE,
677 __builtin_return_address(0));
679 if (ret) {
680 find_vm_area(addr)->flags |= VM_KASAN;
681 kmemleak_ignore(ret);
682 return 0;
685 return -ENOMEM;
688 void kasan_free_shadow(const struct vm_struct *vm)
690 if (vm->flags & VM_KASAN)
691 vfree(kasan_mem_to_shadow(vm->addr));
694 static void register_global(struct kasan_global *global)
696 size_t aligned_size = round_up(global->size, KASAN_SHADOW_SCALE_SIZE);
698 kasan_unpoison_shadow(global->beg, global->size);
700 kasan_poison_shadow(global->beg + aligned_size,
701 global->size_with_redzone - aligned_size,
702 KASAN_GLOBAL_REDZONE);
705 void __asan_register_globals(struct kasan_global *globals, size_t size)
707 int i;
709 for (i = 0; i < size; i++)
710 register_global(&globals[i]);
712 EXPORT_SYMBOL(__asan_register_globals);
714 void __asan_unregister_globals(struct kasan_global *globals, size_t size)
717 EXPORT_SYMBOL(__asan_unregister_globals);
719 #define DEFINE_ASAN_LOAD_STORE(size) \
720 void __asan_load##size(unsigned long addr) \
722 check_memory_region_inline(addr, size, false, _RET_IP_);\
724 EXPORT_SYMBOL(__asan_load##size); \
725 __alias(__asan_load##size) \
726 void __asan_load##size##_noabort(unsigned long); \
727 EXPORT_SYMBOL(__asan_load##size##_noabort); \
728 void __asan_store##size(unsigned long addr) \
730 check_memory_region_inline(addr, size, true, _RET_IP_); \
732 EXPORT_SYMBOL(__asan_store##size); \
733 __alias(__asan_store##size) \
734 void __asan_store##size##_noabort(unsigned long); \
735 EXPORT_SYMBOL(__asan_store##size##_noabort)
737 DEFINE_ASAN_LOAD_STORE(1);
738 DEFINE_ASAN_LOAD_STORE(2);
739 DEFINE_ASAN_LOAD_STORE(4);
740 DEFINE_ASAN_LOAD_STORE(8);
741 DEFINE_ASAN_LOAD_STORE(16);
743 void __asan_loadN(unsigned long addr, size_t size)
745 check_memory_region(addr, size, false, _RET_IP_);
747 EXPORT_SYMBOL(__asan_loadN);
749 __alias(__asan_loadN)
750 void __asan_loadN_noabort(unsigned long, size_t);
751 EXPORT_SYMBOL(__asan_loadN_noabort);
753 void __asan_storeN(unsigned long addr, size_t size)
755 check_memory_region(addr, size, true, _RET_IP_);
757 EXPORT_SYMBOL(__asan_storeN);
759 __alias(__asan_storeN)
760 void __asan_storeN_noabort(unsigned long, size_t);
761 EXPORT_SYMBOL(__asan_storeN_noabort);
763 /* to shut up compiler complaints */
764 void __asan_handle_no_return(void) {}
765 EXPORT_SYMBOL(__asan_handle_no_return);
767 /* Emitted by compiler to poison large objects when they go out of scope. */
768 void __asan_poison_stack_memory(const void *addr, size_t size)
771 * Addr is KASAN_SHADOW_SCALE_SIZE-aligned and the object is surrounded
772 * by redzones, so we simply round up size to simplify logic.
774 kasan_poison_shadow(addr, round_up(size, KASAN_SHADOW_SCALE_SIZE),
775 KASAN_USE_AFTER_SCOPE);
777 EXPORT_SYMBOL(__asan_poison_stack_memory);
779 /* Emitted by compiler to unpoison large objects when they go into scope. */
780 void __asan_unpoison_stack_memory(const void *addr, size_t size)
782 kasan_unpoison_shadow(addr, size);
784 EXPORT_SYMBOL(__asan_unpoison_stack_memory);
786 #ifdef CONFIG_MEMORY_HOTPLUG
787 static int kasan_mem_notifier(struct notifier_block *nb,
788 unsigned long action, void *data)
790 return (action == MEM_GOING_ONLINE) ? NOTIFY_BAD : NOTIFY_OK;
793 static int __init kasan_memhotplug_init(void)
795 pr_info("WARNING: KASAN doesn't support memory hot-add\n");
796 pr_info("Memory hot-add will be disabled\n");
798 hotplug_memory_notifier(kasan_mem_notifier, 0);
800 return 0;
803 module_init(kasan_memhotplug_init);
804 #endif