2 * Handle caching attributes in page tables (PAT)
4 * Authors: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
5 * Suresh B Siddha <suresh.b.siddha@intel.com>
7 * Loosely based on earlier PAT patchset from Eric Biederman and Andi Kleen.
10 #include <linux/seq_file.h>
11 #include <linux/bootmem.h>
12 #include <linux/debugfs.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/gfp.h>
18 #include <linux/rbtree.h>
20 #include <asm/cacheflush.h>
21 #include <asm/processor.h>
22 #include <asm/tlbflush.h>
23 #include <asm/x86_init.h>
24 #include <asm/pgtable.h>
25 #include <asm/fcntl.h>
33 #include "pat_internal.h"
36 int __read_mostly pat_enabled = 1;
38 static inline void pat_disable(const char *reason)
41 printk(KERN_INFO "%s\n", reason);
44 static int __init nopat(char *str)
46 pat_disable("PAT support disabled.");
49 early_param("nopat", nopat);
51 static inline void pat_disable(const char *reason)
60 static int __init pat_debug_setup(char *str)
65 __setup("debugpat", pat_debug_setup);
67 static u64 __read_mostly boot_pat_state;
70 PAT_UC = 0, /* uncached */
71 PAT_WC = 1, /* Write combining */
72 PAT_WT = 4, /* Write Through */
73 PAT_WP = 5, /* Write Protected */
74 PAT_WB = 6, /* Write Back (default) */
75 PAT_UC_MINUS = 7, /* UC, but can be overriden by MTRR */
78 #define PAT(x, y) ((u64)PAT_ ## y << ((x)*8))
83 bool boot_cpu = !boot_pat_state;
89 if (!boot_pat_state) {
90 pat_disable("PAT not supported by CPU.");
94 * If this happens we are on a secondary CPU, but
95 * switched to PAT on the boot CPU. We have no way to
98 printk(KERN_ERR "PAT enabled, "
99 "but not supported by secondary CPU\n");
104 /* Set PWT to Write-Combining. All other bits stay the same */
106 * PTE encoding used in Linux:
111 * 000 WB _PAGE_CACHE_WB
112 * 001 WC _PAGE_CACHE_WC
113 * 010 UC- _PAGE_CACHE_UC_MINUS
114 * 011 UC _PAGE_CACHE_UC
117 pat = PAT(0, WB) | PAT(1, WC) | PAT(2, UC_MINUS) | PAT(3, UC) |
118 PAT(4, WB) | PAT(5, WC) | PAT(6, UC_MINUS) | PAT(7, UC);
122 rdmsrl(MSR_IA32_CR_PAT, boot_pat_state);
124 wrmsrl(MSR_IA32_CR_PAT, pat);
127 printk(KERN_INFO "x86 PAT enabled: cpu %d, old 0x%Lx, new 0x%Lx\n",
128 smp_processor_id(), boot_pat_state, pat);
134 * The global memtype list keeps track of memory type for specific
135 * physical memory areas. Conflicting memory types in different
136 * mappings can cause CPU cache corruption. To avoid this we keep track.
138 * The list is sorted based on starting address and can contain multiple
139 * entries for each address (this allows reference counting for overlapping
140 * areas). All the aliases have the same cache attributes of course.
141 * Zero attributes are represented as holes.
143 * The data structure is a list that is also organized as an rbtree
144 * sorted on the start address of memtype range.
146 * memtype_lock protects both the linear list and rbtree.
149 static struct rb_root memtype_rbroot = RB_ROOT;
150 static LIST_HEAD(memtype_list);
151 static DEFINE_SPINLOCK(memtype_lock); /* protects memtype list */
153 static struct memtype *memtype_rb_search(struct rb_root *root, u64 start)
155 struct rb_node *node = root->rb_node;
156 struct memtype *last_lower = NULL;
159 struct memtype *data = container_of(node, struct memtype, rb);
161 if (data->start < start) {
163 node = node->rb_right;
164 } else if (data->start > start) {
165 node = node->rb_left;
170 /* Will return NULL if there is no entry with its start <= start */
174 static void memtype_rb_insert(struct rb_root *root, struct memtype *data)
176 struct rb_node **new = &(root->rb_node);
177 struct rb_node *parent = NULL;
180 struct memtype *this = container_of(*new, struct memtype, rb);
183 if (data->start <= this->start)
184 new = &((*new)->rb_left);
185 else if (data->start > this->start)
186 new = &((*new)->rb_right);
189 rb_link_node(&data->rb, parent, new);
190 rb_insert_color(&data->rb, root);
194 * Does intersection of PAT memory type and MTRR memory type and returns
195 * the resulting memory type as PAT understands it.
196 * (Type in pat and mtrr will not have same value)
197 * The intersection is based on "Effective Memory Type" tables in IA-32
200 static unsigned long pat_x_mtrr_type(u64 start, u64 end, unsigned long req_type)
203 * Look for MTRR hint to get the effective type in case where PAT
206 if (req_type == _PAGE_CACHE_WB) {
209 mtrr_type = mtrr_type_lookup(start, end);
210 if (mtrr_type != MTRR_TYPE_WRBACK)
211 return _PAGE_CACHE_UC_MINUS;
213 return _PAGE_CACHE_WB;
220 chk_conflict(struct memtype *new, struct memtype *entry, unsigned long *type)
222 if (new->type != entry->type) {
224 new->type = entry->type;
230 /* check overlaps with more than one entry in the list */
231 list_for_each_entry_continue(entry, &memtype_list, nd) {
232 if (new->end <= entry->start)
234 else if (new->type != entry->type)
240 printk(KERN_INFO "%s:%d conflicting memory types "
241 "%Lx-%Lx %s<->%s\n", current->comm, current->pid, new->start,
242 new->end, cattr_name(new->type), cattr_name(entry->type));
246 static int pat_pagerange_is_ram(unsigned long start, unsigned long end)
248 int ram_page = 0, not_rampage = 0;
249 unsigned long page_nr;
251 for (page_nr = (start >> PAGE_SHIFT); page_nr < (end >> PAGE_SHIFT);
254 * For legacy reasons, physical address range in the legacy ISA
255 * region is tracked as non-RAM. This will allow users of
256 * /dev/mem to map portions of legacy ISA region, even when
257 * some of those portions are listed(or not even listed) with
258 * different e820 types(RAM/reserved/..)
260 if (page_nr >= (ISA_END_ADDRESS >> PAGE_SHIFT) &&
261 page_is_ram(page_nr))
266 if (ram_page == not_rampage)
274 * For RAM pages, we use page flags to mark the pages with appropriate type.
275 * Here we do two pass:
276 * - Find the memtype of all the pages in the range, look for any conflicts
277 * - In case of no conflicts, set the new memtype for pages in the range
279 * Caller must hold memtype_lock for atomicity.
281 static int reserve_ram_pages_type(u64 start, u64 end, unsigned long req_type,
282 unsigned long *new_type)
287 if (req_type == _PAGE_CACHE_UC) {
288 /* We do not support strong UC */
290 req_type = _PAGE_CACHE_UC_MINUS;
293 for (pfn = (start >> PAGE_SHIFT); pfn < (end >> PAGE_SHIFT); ++pfn) {
296 page = pfn_to_page(pfn);
297 type = get_page_memtype(page);
299 printk(KERN_INFO "reserve_ram_pages_type failed "
300 "0x%Lx-0x%Lx, track 0x%lx, req 0x%lx\n",
301 start, end, type, req_type);
310 *new_type = req_type;
312 for (pfn = (start >> PAGE_SHIFT); pfn < (end >> PAGE_SHIFT); ++pfn) {
313 page = pfn_to_page(pfn);
314 set_page_memtype(page, req_type);
319 static int free_ram_pages_type(u64 start, u64 end)
324 for (pfn = (start >> PAGE_SHIFT); pfn < (end >> PAGE_SHIFT); ++pfn) {
325 page = pfn_to_page(pfn);
326 set_page_memtype(page, -1);
331 static int memtype_check_insert(struct memtype *new, unsigned long *new_type)
333 struct memtype *entry;
335 unsigned long actual_type;
336 struct list_head *where;
341 actual_type = new->type;
343 /* Search for existing mapping that overlaps the current range */
345 list_for_each_entry(entry, &memtype_list, nd) {
346 if (end <= entry->start) {
347 where = entry->nd.prev;
349 } else if (start <= entry->start) { /* end > entry->start */
350 err = chk_conflict(new, entry, new_type);
352 dprintk("Overlap at 0x%Lx-0x%Lx\n",
353 entry->start, entry->end);
354 where = entry->nd.prev;
357 } else if (start < entry->end) { /* start > entry->start */
358 err = chk_conflict(new, entry, new_type);
360 dprintk("Overlap at 0x%Lx-0x%Lx\n",
361 entry->start, entry->end);
364 * Move to right position in the linked
365 * list to add this new entry
367 list_for_each_entry_continue(entry,
369 if (start <= entry->start) {
370 where = entry->nd.prev;
380 list_add(&new->nd, where);
382 list_add_tail(&new->nd, &memtype_list);
384 memtype_rb_insert(&memtype_rbroot, new);
390 * req_type typically has one of the:
393 * - _PAGE_CACHE_UC_MINUS
396 * If new_type is NULL, function will return an error if it cannot reserve the
397 * region with req_type. If new_type is non-NULL, function will return
398 * available type in new_type in case of no error. In case of any error
399 * it will return a negative return value.
401 int reserve_memtype(u64 start, u64 end, unsigned long req_type,
402 unsigned long *new_type)
405 unsigned long actual_type;
409 BUG_ON(start >= end); /* end is exclusive */
412 /* This is identical to page table setting without PAT */
414 if (req_type == _PAGE_CACHE_WC)
415 *new_type = _PAGE_CACHE_UC_MINUS;
417 *new_type = req_type & _PAGE_CACHE_MASK;
422 /* Low ISA region is always mapped WB in page table. No need to track */
423 if (x86_platform.is_untracked_pat_range(start, end)) {
425 *new_type = _PAGE_CACHE_WB;
430 * Call mtrr_lookup to get the type hint. This is an
431 * optimization for /dev/mem mmap'ers into WB memory (BIOS
432 * tools and ACPI tools). Use WB request for WB memory and use
433 * UC_MINUS otherwise.
435 actual_type = pat_x_mtrr_type(start, end, req_type & _PAGE_CACHE_MASK);
438 *new_type = actual_type;
440 is_range_ram = pat_pagerange_is_ram(start, end);
441 if (is_range_ram == 1) {
443 spin_lock(&memtype_lock);
444 err = reserve_ram_pages_type(start, end, req_type, new_type);
445 spin_unlock(&memtype_lock);
448 } else if (is_range_ram < 0) {
452 new = kmalloc(sizeof(struct memtype), GFP_KERNEL);
458 new->type = actual_type;
460 spin_lock(&memtype_lock);
462 err = memtype_check_insert(new, new_type);
464 printk(KERN_INFO "reserve_memtype failed 0x%Lx-0x%Lx, "
465 "track %s, req %s\n",
466 start, end, cattr_name(new->type), cattr_name(req_type));
468 spin_unlock(&memtype_lock);
473 spin_unlock(&memtype_lock);
475 dprintk("reserve_memtype added 0x%Lx-0x%Lx, track %s, req %s, ret %s\n",
476 start, end, cattr_name(new->type), cattr_name(req_type),
477 new_type ? cattr_name(*new_type) : "-");
482 int free_memtype(u64 start, u64 end)
484 struct memtype *entry, *saved_entry;
491 /* Low ISA region is always mapped WB. No need to track */
492 if (x86_platform.is_untracked_pat_range(start, end))
495 is_range_ram = pat_pagerange_is_ram(start, end);
496 if (is_range_ram == 1) {
498 spin_lock(&memtype_lock);
499 err = free_ram_pages_type(start, end);
500 spin_unlock(&memtype_lock);
503 } else if (is_range_ram < 0) {
507 spin_lock(&memtype_lock);
509 entry = memtype_rb_search(&memtype_rbroot, start);
510 if (unlikely(entry == NULL))
514 * Saved entry points to an entry with start same or less than what
515 * we searched for. Now go through the list in both directions to look
516 * for the entry that matches with both start and end, with list stored
517 * in sorted start address
520 list_for_each_entry_from(entry, &memtype_list, nd) {
521 if (entry->start == start && entry->end == end) {
522 rb_erase(&entry->rb, &memtype_rbroot);
523 list_del(&entry->nd);
527 } else if (entry->start > start) {
536 list_for_each_entry_reverse(entry, &memtype_list, nd) {
537 if (entry->start == start && entry->end == end) {
538 rb_erase(&entry->rb, &memtype_rbroot);
539 list_del(&entry->nd);
543 } else if (entry->start < start) {
548 spin_unlock(&memtype_lock);
551 printk(KERN_INFO "%s:%d freeing invalid memtype %Lx-%Lx\n",
552 current->comm, current->pid, start, end);
555 dprintk("free_memtype request 0x%Lx-0x%Lx\n", start, end);
562 * lookup_memtype - Looksup the memory type for a physical address
563 * @paddr: physical address of which memory type needs to be looked up
565 * Only to be called when PAT is enabled
567 * Returns _PAGE_CACHE_WB, _PAGE_CACHE_WC, _PAGE_CACHE_UC_MINUS or
570 static unsigned long lookup_memtype(u64 paddr)
572 int rettype = _PAGE_CACHE_WB;
573 struct memtype *entry;
575 if (x86_platform.is_untracked_pat_range(paddr, paddr + PAGE_SIZE))
578 if (pat_pagerange_is_ram(paddr, paddr + PAGE_SIZE)) {
580 spin_lock(&memtype_lock);
581 page = pfn_to_page(paddr >> PAGE_SHIFT);
582 rettype = get_page_memtype(page);
583 spin_unlock(&memtype_lock);
585 * -1 from get_page_memtype() implies RAM page is in its
586 * default state and not reserved, and hence of type WB
589 rettype = _PAGE_CACHE_WB;
594 spin_lock(&memtype_lock);
596 entry = memtype_rb_search(&memtype_rbroot, paddr);
598 rettype = entry->type;
600 rettype = _PAGE_CACHE_UC_MINUS;
602 spin_unlock(&memtype_lock);
607 * io_reserve_memtype - Request a memory type mapping for a region of memory
608 * @start: start (physical address) of the region
609 * @end: end (physical address) of the region
610 * @type: A pointer to memtype, with requested type. On success, requested
611 * or any other compatible type that was available for the region is returned
613 * On success, returns 0
614 * On failure, returns non-zero
616 int io_reserve_memtype(resource_size_t start, resource_size_t end,
619 resource_size_t size = end - start;
620 unsigned long req_type = *type;
621 unsigned long new_type;
624 WARN_ON_ONCE(iomem_map_sanity_check(start, size));
626 ret = reserve_memtype(start, end, req_type, &new_type);
630 if (!is_new_memtype_allowed(start, size, req_type, new_type))
633 if (kernel_map_sync_memtype(start, size, new_type) < 0)
640 free_memtype(start, end);
647 * io_free_memtype - Release a memory type mapping for a region of memory
648 * @start: start (physical address) of the region
649 * @end: end (physical address) of the region
651 void io_free_memtype(resource_size_t start, resource_size_t end)
653 free_memtype(start, end);
656 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
657 unsigned long size, pgprot_t vma_prot)
662 #ifdef CONFIG_STRICT_DEVMEM
663 /* This check is done in drivers/char/mem.c in case of STRICT_DEVMEM*/
664 static inline int range_is_allowed(unsigned long pfn, unsigned long size)
669 /* This check is needed to avoid cache aliasing when PAT is enabled */
670 static inline int range_is_allowed(unsigned long pfn, unsigned long size)
672 u64 from = ((u64)pfn) << PAGE_SHIFT;
673 u64 to = from + size;
679 while (cursor < to) {
680 if (!devmem_is_allowed(pfn)) {
682 "Program %s tried to access /dev/mem between %Lx->%Lx.\n",
683 current->comm, from, to);
691 #endif /* CONFIG_STRICT_DEVMEM */
693 int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn,
694 unsigned long size, pgprot_t *vma_prot)
696 unsigned long flags = _PAGE_CACHE_WB;
698 if (!range_is_allowed(pfn, size))
701 if (file->f_flags & O_DSYNC)
702 flags = _PAGE_CACHE_UC_MINUS;
706 * On the PPro and successors, the MTRRs are used to set
707 * memory types for physical addresses outside main memory,
708 * so blindly setting UC or PWT on those pages is wrong.
709 * For Pentiums and earlier, the surround logic should disable
710 * caching for the high addresses through the KEN pin, but
711 * we maintain the tradition of paranoia in this code.
714 !(boot_cpu_has(X86_FEATURE_MTRR) ||
715 boot_cpu_has(X86_FEATURE_K6_MTRR) ||
716 boot_cpu_has(X86_FEATURE_CYRIX_ARR) ||
717 boot_cpu_has(X86_FEATURE_CENTAUR_MCR)) &&
718 (pfn << PAGE_SHIFT) >= __pa(high_memory)) {
719 flags = _PAGE_CACHE_UC;
723 *vma_prot = __pgprot((pgprot_val(*vma_prot) & ~_PAGE_CACHE_MASK) |
729 * Change the memory type for the physial address range in kernel identity
730 * mapping space if that range is a part of identity map.
732 int kernel_map_sync_memtype(u64 base, unsigned long size, unsigned long flags)
736 if (base >= __pa(high_memory))
739 id_sz = (__pa(high_memory) < base + size) ?
740 __pa(high_memory) - base :
743 if (ioremap_change_attr((unsigned long)__va(base), id_sz, flags) < 0) {
745 "%s:%d ioremap_change_attr failed %s "
747 current->comm, current->pid,
749 base, (unsigned long long)(base + size));
756 * Internal interface to reserve a range of physical memory with prot.
757 * Reserved non RAM regions only and after successful reserve_memtype,
758 * this func also keeps identity mapping (if any) in sync with this new prot.
760 static int reserve_pfn_range(u64 paddr, unsigned long size, pgprot_t *vma_prot,
765 unsigned long want_flags = (pgprot_val(*vma_prot) & _PAGE_CACHE_MASK);
766 unsigned long flags = want_flags;
768 is_ram = pat_pagerange_is_ram(paddr, paddr + size);
771 * reserve_pfn_range() for RAM pages. We do not refcount to keep
772 * track of number of mappings of RAM pages. We can assert that
773 * the type requested matches the type of first page in the range.
779 flags = lookup_memtype(paddr);
780 if (want_flags != flags) {
782 "%s:%d map pfn RAM range req %s for %Lx-%Lx, got %s\n",
783 current->comm, current->pid,
784 cattr_name(want_flags),
785 (unsigned long long)paddr,
786 (unsigned long long)(paddr + size),
788 *vma_prot = __pgprot((pgprot_val(*vma_prot) &
789 (~_PAGE_CACHE_MASK)) |
795 ret = reserve_memtype(paddr, paddr + size, want_flags, &flags);
799 if (flags != want_flags) {
801 !is_new_memtype_allowed(paddr, size, want_flags, flags)) {
802 free_memtype(paddr, paddr + size);
803 printk(KERN_ERR "%s:%d map pfn expected mapping type %s"
804 " for %Lx-%Lx, got %s\n",
805 current->comm, current->pid,
806 cattr_name(want_flags),
807 (unsigned long long)paddr,
808 (unsigned long long)(paddr + size),
813 * We allow returning different type than the one requested in
816 *vma_prot = __pgprot((pgprot_val(*vma_prot) &
817 (~_PAGE_CACHE_MASK)) |
821 if (kernel_map_sync_memtype(paddr, size, flags) < 0) {
822 free_memtype(paddr, paddr + size);
829 * Internal interface to free a range of physical memory.
830 * Frees non RAM regions only.
832 static void free_pfn_range(u64 paddr, unsigned long size)
836 is_ram = pat_pagerange_is_ram(paddr, paddr + size);
838 free_memtype(paddr, paddr + size);
842 * track_pfn_vma_copy is called when vma that is covering the pfnmap gets
843 * copied through copy_page_range().
845 * If the vma has a linear pfn mapping for the entire range, we get the prot
846 * from pte and reserve the entire vma range with single reserve_pfn_range call.
848 int track_pfn_vma_copy(struct vm_area_struct *vma)
850 resource_size_t paddr;
852 unsigned long vma_size = vma->vm_end - vma->vm_start;
855 if (is_linear_pfn_mapping(vma)) {
857 * reserve the whole chunk covered by vma. We need the
858 * starting address and protection from pte.
860 if (follow_phys(vma, vma->vm_start, 0, &prot, &paddr)) {
864 pgprot = __pgprot(prot);
865 return reserve_pfn_range(paddr, vma_size, &pgprot, 1);
872 * track_pfn_vma_new is called when a _new_ pfn mapping is being established
873 * for physical range indicated by pfn and size.
875 * prot is passed in as a parameter for the new mapping. If the vma has a
876 * linear pfn mapping for the entire range reserve the entire vma range with
877 * single reserve_pfn_range call.
879 int track_pfn_vma_new(struct vm_area_struct *vma, pgprot_t *prot,
880 unsigned long pfn, unsigned long size)
883 resource_size_t paddr;
884 unsigned long vma_size = vma->vm_end - vma->vm_start;
886 if (is_linear_pfn_mapping(vma)) {
887 /* reserve the whole chunk starting from vm_pgoff */
888 paddr = (resource_size_t)vma->vm_pgoff << PAGE_SHIFT;
889 return reserve_pfn_range(paddr, vma_size, prot, 0);
895 /* for vm_insert_pfn and friends, we set prot based on lookup */
896 flags = lookup_memtype(pfn << PAGE_SHIFT);
897 *prot = __pgprot((pgprot_val(vma->vm_page_prot) & (~_PAGE_CACHE_MASK)) |
904 * untrack_pfn_vma is called while unmapping a pfnmap for a region.
905 * untrack can be called for a specific region indicated by pfn and size or
906 * can be for the entire vma (in which case size can be zero).
908 void untrack_pfn_vma(struct vm_area_struct *vma, unsigned long pfn,
911 resource_size_t paddr;
912 unsigned long vma_size = vma->vm_end - vma->vm_start;
914 if (is_linear_pfn_mapping(vma)) {
915 /* free the whole chunk starting from vm_pgoff */
916 paddr = (resource_size_t)vma->vm_pgoff << PAGE_SHIFT;
917 free_pfn_range(paddr, vma_size);
922 pgprot_t pgprot_writecombine(pgprot_t prot)
925 return __pgprot(pgprot_val(prot) | _PAGE_CACHE_WC);
927 return pgprot_noncached(prot);
929 EXPORT_SYMBOL_GPL(pgprot_writecombine);
931 #if defined(CONFIG_DEBUG_FS) && defined(CONFIG_X86_PAT)
933 /* get Nth element of the linked list */
934 static int copy_memtype_nth_element(struct memtype *out, loff_t pos)
936 struct memtype *list_node;
939 list_for_each_entry(list_node, &memtype_list, nd) {
949 static struct memtype *memtype_get_idx(loff_t pos)
951 struct memtype *print_entry;
954 print_entry = kzalloc(sizeof(struct memtype), GFP_KERNEL);
958 spin_lock(&memtype_lock);
959 ret = copy_memtype_nth_element(print_entry, pos);
960 spin_unlock(&memtype_lock);
970 static void *memtype_seq_start(struct seq_file *seq, loff_t *pos)
974 seq_printf(seq, "PAT memtype list:\n");
977 return memtype_get_idx(*pos);
980 static void *memtype_seq_next(struct seq_file *seq, void *v, loff_t *pos)
983 return memtype_get_idx(*pos);
986 static void memtype_seq_stop(struct seq_file *seq, void *v)
990 static int memtype_seq_show(struct seq_file *seq, void *v)
992 struct memtype *print_entry = (struct memtype *)v;
994 seq_printf(seq, "%s @ 0x%Lx-0x%Lx\n", cattr_name(print_entry->type),
995 print_entry->start, print_entry->end);
1001 static const struct seq_operations memtype_seq_ops = {
1002 .start = memtype_seq_start,
1003 .next = memtype_seq_next,
1004 .stop = memtype_seq_stop,
1005 .show = memtype_seq_show,
1008 static int memtype_seq_open(struct inode *inode, struct file *file)
1010 return seq_open(file, &memtype_seq_ops);
1013 static const struct file_operations memtype_fops = {
1014 .open = memtype_seq_open,
1016 .llseek = seq_lseek,
1017 .release = seq_release,
1020 static int __init pat_memtype_list_init(void)
1023 debugfs_create_file("pat_memtype_list", S_IRUSR,
1024 arch_debugfs_dir, NULL, &memtype_fops);
1029 late_initcall(pat_memtype_list_init);
1031 #endif /* CONFIG_DEBUG_FS && CONFIG_X86_PAT */