diff --git a/arch/alpha/include/asm/vmalloc.h b/arch/alpha/include/asm/vmalloc.h
new file mode 100644
index 00000000000000..0a9a366a4d344e
--- /dev/null
+++ b/arch/alpha/include/asm/vmalloc.h
@@ -0,0 +1,4 @@
+#ifndef _ASM_ALPHA_VMALLOC_H
+#define _ASM_ALPHA_VMALLOC_H
+
+#endif /* _ASM_ALPHA_VMALLOC_H */
diff --git a/arch/arc/include/asm/vmalloc.h b/arch/arc/include/asm/vmalloc.h
new file mode 100644
index 00000000000000..973095aad665ad
--- /dev/null
+++ b/arch/arc/include/asm/vmalloc.h
@@ -0,0 +1,4 @@
+#ifndef _ASM_ARC_VMALLOC_H
+#define _ASM_ARC_VMALLOC_H
+
+#endif /* _ASM_ARC_VMALLOC_H */
diff --git a/arch/arm/include/asm/vmalloc.h b/arch/arm/include/asm/vmalloc.h
new file mode 100644
index 00000000000000..a9b3718b8600b7
--- /dev/null
+++ b/arch/arm/include/asm/vmalloc.h
@@ -0,0 +1,4 @@
+#ifndef _ASM_ARM_VMALLOC_H
+#define _ASM_ARM_VMALLOC_H
+
+#endif /* _ASM_ARM_VMALLOC_H */
diff --git a/arch/arm64/include/asm/vmalloc.h b/arch/arm64/include/asm/vmalloc.h
new file mode 100644
index 00000000000000..2ca708ab9b20b0
--- /dev/null
+++ b/arch/arm64/include/asm/vmalloc.h
@@ -0,0 +1,4 @@
+#ifndef _ASM_ARM64_VMALLOC_H
+#define _ASM_ARM64_VMALLOC_H
+
+#endif /* _ASM_ARM64_VMALLOC_H */
diff --git a/arch/c6x/include/asm/vmalloc.h b/arch/c6x/include/asm/vmalloc.h
new file mode 100644
index 00000000000000..26c6c6696bbd95
--- /dev/null
+++ b/arch/c6x/include/asm/vmalloc.h
@@ -0,0 +1,4 @@
+#ifndef _ASM_C6X_VMALLOC_H
+#define _ASM_C6X_VMALLOC_H
+
+#endif /* _ASM_C6X_VMALLOC_H */
diff --git a/arch/csky/include/asm/vmalloc.h b/arch/csky/include/asm/vmalloc.h
new file mode 100644
index 00000000000000..43dca6336b4c67
--- /dev/null
+++ b/arch/csky/include/asm/vmalloc.h
@@ -0,0 +1,4 @@
+#ifndef _ASM_CSKY_VMALLOC_H
+#define _ASM_CSKY_VMALLOC_H
+
+#endif /* _ASM_CSKY_VMALLOC_H */
diff --git a/arch/h8300/include/asm/vmalloc.h b/arch/h8300/include/asm/vmalloc.h
new file mode 100644
index 00000000000000..08a55c1dfa23c5
--- /dev/null
+++ b/arch/h8300/include/asm/vmalloc.h
@@ -0,0 +1,4 @@
+#ifndef _ASM_H8300_VMALLOC_H
+#define _ASM_H8300_VMALLOC_H
+
+#endif /* _ASM_H8300_VMALLOC_H */
diff --git a/arch/hexagon/include/asm/vmalloc.h b/arch/hexagon/include/asm/vmalloc.h
new file mode 100644
index 00000000000000..7b04609e525c4b
--- /dev/null
+++ b/arch/hexagon/include/asm/vmalloc.h
@@ -0,0 +1,4 @@
+#ifndef _ASM_HEXAGON_VMALLOC_H
+#define _ASM_HEXAGON_VMALLOC_H
+
+#endif /* _ASM_HEXAGON_VMALLOC_H */
diff --git a/arch/ia64/include/asm/vmalloc.h b/arch/ia64/include/asm/vmalloc.h
new file mode 100644
index 00000000000000..a2b51141ad2850
--- /dev/null
+++ b/arch/ia64/include/asm/vmalloc.h
@@ -0,0 +1,4 @@
+#ifndef _ASM_IA64_VMALLOC_H
+#define _ASM_IA64_VMALLOC_H
+
+#endif /* _ASM_IA64_VMALLOC_H */
diff --git a/arch/m68k/include/asm/vmalloc.h b/arch/m68k/include/asm/vmalloc.h
new file mode 100644
index 00000000000000..bc1dca6cf134f6
--- /dev/null
+++ b/arch/m68k/include/asm/vmalloc.h
@@ -0,0 +1,4 @@
+#ifndef _ASM_M68K_VMALLOC_H
+#define _ASM_M68K_VMALLOC_H
+
+#endif /* _ASM_M68K_VMALLOC_H */
diff --git a/arch/microblaze/include/asm/vmalloc.h b/arch/microblaze/include/asm/vmalloc.h
new file mode 100644
index 00000000000000..04013a42b0fec8
--- /dev/null
+++ b/arch/microblaze/include/asm/vmalloc.h
@@ -0,0 +1,4 @@
+#ifndef _ASM_MICROBLAZE_VMALLOC_H
+#define _ASM_MICROBLAZE_VMALLOC_H
+
+#endif /* _ASM_MICROBLAZE_VMALLOC_H */
diff --git a/arch/mips/include/asm/vmalloc.h b/arch/mips/include/asm/vmalloc.h
new file mode 100644
index 00000000000000..25dc09b25eaf98
--- /dev/null
+++ b/arch/mips/include/asm/vmalloc.h
@@ -0,0 +1,4 @@
+#ifndef _ASM_MIPS_VMALLOC_H
+#define _ASM_MIPS_VMALLOC_H
+
+#endif /* _ASM_MIPS_VMALLOC_H */
diff --git a/arch/nds32/include/asm/vmalloc.h b/arch/nds32/include/asm/vmalloc.h
new file mode 100644
index 00000000000000..caeed389841944
--- /dev/null
+++ b/arch/nds32/include/asm/vmalloc.h
@@ -0,0 +1,4 @@
+#ifndef _ASM_NDS32_VMALLOC_H
+#define _ASM_NDS32_VMALLOC_H
+
+#endif /* _ASM_NDS32_VMALLOC_H */
diff --git a/arch/nios2/include/asm/vmalloc.h b/arch/nios2/include/asm/vmalloc.h
new file mode 100644
index 00000000000000..ec7a9260090bcc
--- /dev/null
+++ b/arch/nios2/include/asm/vmalloc.h
@@ -0,0 +1,4 @@
+#ifndef _ASM_NIOS2_VMALLOC_H
+#define _ASM_NIOS2_VMALLOC_H
+
+#endif /* _ASM_NIOS2_VMALLOC_H */
diff --git a/arch/openrisc/include/asm/vmalloc.h b/arch/openrisc/include/asm/vmalloc.h
new file mode 100644
index 00000000000000..75435eceec32a9
--- /dev/null
+++ b/arch/openrisc/include/asm/vmalloc.h
@@ -0,0 +1,4 @@
+#ifndef _ASM_OPENRISC_VMALLOC_H
+#define _ASM_OPENRISC_VMALLOC_H
+
+#endif /* _ASM_OPENRISC_VMALLOC_H */
diff --git a/arch/parisc/include/asm/vmalloc.h b/arch/parisc/include/asm/vmalloc.h
new file mode 100644
index 00000000000000..1088ae4e7af9fe
--- /dev/null
+++ b/arch/parisc/include/asm/vmalloc.h
@@ -0,0 +1,4 @@
+#ifndef _ASM_PARISC_VMALLOC_H
+#define _ASM_PARISC_VMALLOC_H
+
+#endif /* _ASM_PARISC_VMALLOC_H */
diff --git a/arch/powerpc/include/asm/vmalloc.h b/arch/powerpc/include/asm/vmalloc.h
new file mode 100644
index 00000000000000..b992dfaaa16181
--- /dev/null
+++ b/arch/powerpc/include/asm/vmalloc.h
@@ -0,0 +1,4 @@
+#ifndef _ASM_POWERPC_VMALLOC_H
+#define _ASM_POWERPC_VMALLOC_H
+
+#endif /* _ASM_POWERPC_VMALLOC_H */
diff --git a/arch/riscv/include/asm/vmalloc.h b/arch/riscv/include/asm/vmalloc.h
new file mode 100644
index 00000000000000..ff9abc00d1394f
--- /dev/null
+++ b/arch/riscv/include/asm/vmalloc.h
@@ -0,0 +1,4 @@
+#ifndef _ASM_RISCV_VMALLOC_H
+#define _ASM_RISCV_VMALLOC_H
+
+#endif /* _ASM_RISCV_VMALLOC_H */
diff --git a/arch/s390/include/asm/vmalloc.h b/arch/s390/include/asm/vmalloc.h
new file mode 100644
index 00000000000000..3ba3a6bdca254a
--- /dev/null
+++ b/arch/s390/include/asm/vmalloc.h
@@ -0,0 +1,4 @@
+#ifndef _ASM_S390_VMALLOC_H
+#define _ASM_S390_VMALLOC_H
+
+#endif /* _ASM_S390_VMALLOC_H */
diff --git a/arch/sh/include/asm/vmalloc.h b/arch/sh/include/asm/vmalloc.h
new file mode 100644
index 00000000000000..716b7747264658
--- /dev/null
+++ b/arch/sh/include/asm/vmalloc.h
@@ -0,0 +1,4 @@
+#ifndef _ASM_SH_VMALLOC_H
+#define _ASM_SH_VMALLOC_H
+
+#endif /* _ASM_SH_VMALLOC_H */
diff --git a/arch/sparc/include/asm/vmalloc.h b/arch/sparc/include/asm/vmalloc.h
new file mode 100644
index 00000000000000..04b8ab9518b88d
--- /dev/null
+++ b/arch/sparc/include/asm/vmalloc.h
@@ -0,0 +1,4 @@
+#ifndef _ASM_SPARC_VMALLOC_H
+#define _ASM_SPARC_VMALLOC_H
+
+#endif /* _ASM_SPARC_VMALLOC_H */
diff --git a/arch/um/include/asm/vmalloc.h b/arch/um/include/asm/vmalloc.h
new file mode 100644
index 00000000000000..9a7b9ed9373370
--- /dev/null
+++ b/arch/um/include/asm/vmalloc.h
@@ -0,0 +1,4 @@
+#ifndef _ASM_UM_VMALLOC_H
+#define _ASM_UM_VMALLOC_H
+
+#endif /* _ASM_UM_VMALLOC_H */
diff --git a/arch/unicore32/include/asm/vmalloc.h b/arch/unicore32/include/asm/vmalloc.h
new file mode 100644
index 00000000000000..054435818a1462
--- /dev/null
+++ b/arch/unicore32/include/asm/vmalloc.h
@@ -0,0 +1,4 @@
+#ifndef _ASM_UNICORE32_VMALLOC_H
+#define _ASM_UNICORE32_VMALLOC_H
+
+#endif /* _ASM_UNICORE32_VMALLOC_H */
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index ded73bb5c0ddff..c1cbfc7b3ae87b 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1512,7 +1512,7 @@ config X86_CPA_STATISTICS
 	bool "Enable statistic for Change Page Attribute"
 	depends on DEBUG_FS
 	---help---
-	  Expose statistics about the Change Page Attribute mechanims, which
+	  Expose statistics about the Change Page Attribute mechanism, which
 	  helps to determine the effectiveness of preserving large and huge
 	  page mappings when mapping protections are changed.
 
diff --git a/arch/x86/include/asm/cpu_entry_area.h b/arch/x86/include/asm/cpu_entry_area.h
index 804734058c778f..02c0078d3787b4 100644
--- a/arch/x86/include/asm/cpu_entry_area.h
+++ b/arch/x86/include/asm/cpu_entry_area.h
@@ -6,6 +6,7 @@
 #include <linux/percpu-defs.h>
 #include <asm/processor.h>
 #include <asm/intel_ds.h>
+#include <asm/pgtable_areas.h>
 
 #ifdef CONFIG_X86_64
 
@@ -134,15 +135,6 @@ DECLARE_PER_CPU(struct cea_exception_stacks *, cea_exception_stacks);
 extern void setup_cpu_entry_areas(void);
 extern void cea_set_pte(void *cea_vaddr, phys_addr_t pa, pgprot_t flags);
 
-/* Single page reserved for the readonly IDT mapping: */
-#define	CPU_ENTRY_AREA_RO_IDT		CPU_ENTRY_AREA_BASE
-#define CPU_ENTRY_AREA_PER_CPU		(CPU_ENTRY_AREA_RO_IDT + PAGE_SIZE)
-
-#define CPU_ENTRY_AREA_RO_IDT_VADDR	((void *)CPU_ENTRY_AREA_RO_IDT)
-
-#define CPU_ENTRY_AREA_MAP_SIZE			\
-	(CPU_ENTRY_AREA_PER_CPU + CPU_ENTRY_AREA_ARRAY_SIZE - CPU_ENTRY_AREA_BASE)
-
 extern struct cpu_entry_area *get_cpu_entry_area(int cpu);
 
 static inline struct entry_stack *cpu_entry_stack(int cpu)
diff --git a/arch/x86/include/asm/memtype.h b/arch/x86/include/asm/memtype.h
new file mode 100644
index 00000000000000..9c2447b3555dc3
--- /dev/null
+++ b/arch/x86/include/asm/memtype.h
@@ -0,0 +1,27 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_X86_MEMTYPE_H
+#define _ASM_X86_MEMTYPE_H
+
+#include <linux/types.h>
+#include <asm/pgtable_types.h>
+
+extern bool pat_enabled(void);
+extern void pat_disable(const char *reason);
+extern void pat_init(void);
+extern void init_cache_modes(void);
+
+extern int memtype_reserve(u64 start, u64 end,
+		enum page_cache_mode req_pcm, enum page_cache_mode *ret_pcm);
+extern int memtype_free(u64 start, u64 end);
+
+extern int memtype_kernel_map_sync(u64 base, unsigned long size,
+		enum page_cache_mode pcm);
+
+extern int memtype_reserve_io(resource_size_t start, resource_size_t end,
+			enum page_cache_mode *pcm);
+
+extern void memtype_free_io(resource_size_t start, resource_size_t end);
+
+extern bool pat_pfn_immune_to_uc_mtrr(unsigned long pfn);
+
+#endif /* _ASM_X86_MEMTYPE_H */
diff --git a/arch/x86/include/asm/mmu_context.h b/arch/x86/include/asm/mmu_context.h
index 5f33924e200fca..b243234e90cb1d 100644
--- a/arch/x86/include/asm/mmu_context.h
+++ b/arch/x86/include/asm/mmu_context.h
@@ -69,14 +69,6 @@ struct ldt_struct {
 	int			slot;
 };
 
-/* This is a multiple of PAGE_SIZE. */
-#define LDT_SLOT_STRIDE (LDT_ENTRIES * LDT_ENTRY_SIZE)
-
-static inline void *ldt_slot_va(int slot)
-{
-	return (void *)(LDT_BASE_ADDR + LDT_SLOT_STRIDE * slot);
-}
-
 /*
  * Used for LDT copy/destruction.
  */
@@ -99,87 +91,21 @@ static inline void destroy_context_ldt(struct mm_struct *mm) { }
 static inline void ldt_arch_exit_mmap(struct mm_struct *mm) { }
 #endif
 
-static inline void load_mm_ldt(struct mm_struct *mm)
-{
 #ifdef CONFIG_MODIFY_LDT_SYSCALL
-	struct ldt_struct *ldt;
-
-	/* READ_ONCE synchronizes with smp_store_release */
-	ldt = READ_ONCE(mm->context.ldt);
-
-	/*
-	 * Any change to mm->context.ldt is followed by an IPI to all
-	 * CPUs with the mm active.  The LDT will not be freed until
-	 * after the IPI is handled by all such CPUs.  This means that,
-	 * if the ldt_struct changes before we return, the values we see
-	 * will be safe, and the new values will be loaded before we run
-	 * any user code.
-	 *
-	 * NB: don't try to convert this to use RCU without extreme care.
-	 * We would still need IRQs off, because we don't want to change
-	 * the local LDT after an IPI loaded a newer value than the one
-	 * that we can see.
-	 */
-
-	if (unlikely(ldt)) {
-		if (static_cpu_has(X86_FEATURE_PTI)) {
-			if (WARN_ON_ONCE((unsigned long)ldt->slot > 1)) {
-				/*
-				 * Whoops -- either the new LDT isn't mapped
-				 * (if slot == -1) or is mapped into a bogus
-				 * slot (if slot > 1).
-				 */
-				clear_LDT();
-				return;
-			}
-
-			/*
-			 * If page table isolation is enabled, ldt->entries
-			 * will not be mapped in the userspace pagetables.
-			 * Tell the CPU to access the LDT through the alias
-			 * at ldt_slot_va(ldt->slot).
-			 */
-			set_ldt(ldt_slot_va(ldt->slot), ldt->nr_entries);
-		} else {
-			set_ldt(ldt->entries, ldt->nr_entries);
-		}
-	} else {
-		clear_LDT();
-	}
+extern void load_mm_ldt(struct mm_struct *mm);
+extern void switch_ldt(struct mm_struct *prev, struct mm_struct *next);
 #else
+static inline void load_mm_ldt(struct mm_struct *mm)
+{
 	clear_LDT();
-#endif
 }
-
 static inline void switch_ldt(struct mm_struct *prev, struct mm_struct *next)
 {
-#ifdef CONFIG_MODIFY_LDT_SYSCALL
-	/*
-	 * Load the LDT if either the old or new mm had an LDT.
-	 *
-	 * An mm will never go from having an LDT to not having an LDT.  Two
-	 * mms never share an LDT, so we don't gain anything by checking to
-	 * see whether the LDT changed.  There's also no guarantee that
-	 * prev->context.ldt actually matches LDTR, but, if LDTR is non-NULL,
-	 * then prev->context.ldt will also be non-NULL.
-	 *
-	 * If we really cared, we could optimize the case where prev == next
-	 * and we're exiting lazy mode.  Most of the time, if this happens,
-	 * we don't actually need to reload LDTR, but modify_ldt() is mostly
-	 * used by legacy code and emulators where we don't need this level of
-	 * performance.
-	 *
-	 * This uses | instead of || because it generates better code.
-	 */
-	if (unlikely((unsigned long)prev->context.ldt |
-		     (unsigned long)next->context.ldt))
-		load_mm_ldt(next);
-#endif
-
 	DEBUG_LOCKS_WARN_ON(preemptible());
 }
+#endif
 
-void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk);
+extern void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk);
 
 /*
  * Init a new mm.  Used on mm copies, like at fork()
diff --git a/arch/x86/include/asm/mtrr.h b/arch/x86/include/asm/mtrr.h
index dbff1456d2152a..829df26fd7a3ec 100644
--- a/arch/x86/include/asm/mtrr.h
+++ b/arch/x86/include/asm/mtrr.h
@@ -24,7 +24,7 @@
 #define _ASM_X86_MTRR_H
 
 #include <uapi/asm/mtrr.h>
-#include <asm/pat.h>
+#include <asm/memtype.h>
 
 
 /*
@@ -86,7 +86,7 @@ static inline void mtrr_centaur_report_mcr(int mcr, u32 lo, u32 hi)
 }
 static inline void mtrr_bp_init(void)
 {
-	pat_disable("MTRRs disabled, skipping PAT initialization too.");
+	pat_disable("PAT support disabled because CONFIG_MTRR is disabled in the kernel.");
 }
 
 #define mtrr_ap_init() do {} while (0)
diff --git a/arch/x86/include/asm/pat.h b/arch/x86/include/asm/pat.h
deleted file mode 100644
index 92015c65fa2ac9..00000000000000
--- a/arch/x86/include/asm/pat.h
+++ /dev/null
@@ -1,27 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_X86_PAT_H
-#define _ASM_X86_PAT_H
-
-#include <linux/types.h>
-#include <asm/pgtable_types.h>
-
-bool pat_enabled(void);
-void pat_disable(const char *reason);
-extern void pat_init(void);
-extern void init_cache_modes(void);
-
-extern int reserve_memtype(u64 start, u64 end,
-		enum page_cache_mode req_pcm, enum page_cache_mode *ret_pcm);
-extern int free_memtype(u64 start, u64 end);
-
-extern int kernel_map_sync_memtype(u64 base, unsigned long size,
-		enum page_cache_mode pcm);
-
-int io_reserve_memtype(resource_size_t start, resource_size_t end,
-			enum page_cache_mode *pcm);
-
-void io_free_memtype(resource_size_t start, resource_size_t end);
-
-bool pat_pfn_immune_to_uc_mtrr(unsigned long pfn);
-
-#endif /* _ASM_X86_PAT_H */
diff --git a/arch/x86/include/asm/pci.h b/arch/x86/include/asm/pci.h
index 90d0731fdcb633..c1fdd43fe18764 100644
--- a/arch/x86/include/asm/pci.h
+++ b/arch/x86/include/asm/pci.h
@@ -9,7 +9,7 @@
 #include <linux/scatterlist.h>
 #include <linux/numa.h>
 #include <asm/io.h>
-#include <asm/pat.h>
+#include <asm/memtype.h>
 #include <asm/x86_init.h>
 
 struct pci_sysdata {
diff --git a/arch/x86/include/asm/pgtable_32_areas.h b/arch/x86/include/asm/pgtable_32_areas.h
new file mode 100644
index 00000000000000..b6355416a15a89
--- /dev/null
+++ b/arch/x86/include/asm/pgtable_32_areas.h
@@ -0,0 +1,53 @@
+#ifndef _ASM_X86_PGTABLE_32_AREAS_H
+#define _ASM_X86_PGTABLE_32_AREAS_H
+
+#include <asm/cpu_entry_area.h>
+
+/*
+ * Just any arbitrary offset to the start of the vmalloc VM area: the
+ * current 8MB value just means that there will be a 8MB "hole" after the
+ * physical memory until the kernel virtual memory starts.  That means that
+ * any out-of-bounds memory accesses will hopefully be caught.
+ * The vmalloc() routines leaves a hole of 4kB between each vmalloced
+ * area for the same reason. ;)
+ */
+#define VMALLOC_OFFSET	(8 * 1024 * 1024)
+
+#ifndef __ASSEMBLY__
+extern bool __vmalloc_start_set; /* set once high_memory is set */
+#endif
+
+#define VMALLOC_START	((unsigned long)high_memory + VMALLOC_OFFSET)
+#ifdef CONFIG_X86_PAE
+#define LAST_PKMAP 512
+#else
+#define LAST_PKMAP 1024
+#endif
+
+#define CPU_ENTRY_AREA_PAGES		(NR_CPUS * DIV_ROUND_UP(sizeof(struct cpu_entry_area), PAGE_SIZE))
+
+/* The +1 is for the readonly IDT page: */
+#define CPU_ENTRY_AREA_BASE	\
+	((FIXADDR_TOT_START - PAGE_SIZE*(CPU_ENTRY_AREA_PAGES+1)) & PMD_MASK)
+
+#define LDT_BASE_ADDR		\
+	((CPU_ENTRY_AREA_BASE - PAGE_SIZE) & PMD_MASK)
+
+#define LDT_END_ADDR		(LDT_BASE_ADDR + PMD_SIZE)
+
+#define PKMAP_BASE		\
+	((LDT_BASE_ADDR - PAGE_SIZE) & PMD_MASK)
+
+#ifdef CONFIG_HIGHMEM
+# define VMALLOC_END	(PKMAP_BASE - 2 * PAGE_SIZE)
+#else
+# define VMALLOC_END	(LDT_BASE_ADDR - 2 * PAGE_SIZE)
+#endif
+
+#define MODULES_VADDR	VMALLOC_START
+#define MODULES_END	VMALLOC_END
+#define MODULES_LEN	(MODULES_VADDR - MODULES_END)
+
+#define MAXMEM	(VMALLOC_END - PAGE_OFFSET - __VMALLOC_RESERVE)
+
+#endif /* _ASM_X86_PGTABLE_32_AREAS_H */
diff --git a/arch/x86/include/asm/pgtable_32_types.h b/arch/x86/include/asm/pgtable_32_types.h
index 0416d42e5bdd9e..5356a46b037355 100644
--- a/arch/x86/include/asm/pgtable_32_types.h
+++ b/arch/x86/include/asm/pgtable_32_types.h
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_X86_PGTABLE_32_DEFS_H
-#define _ASM_X86_PGTABLE_32_DEFS_H
+#ifndef _ASM_X86_PGTABLE_32_TYPES_H
+#define _ASM_X86_PGTABLE_32_TYPES_H
 
 /*
  * The Linux x86 paging architecture is 'compile-time dual-mode', it
@@ -20,55 +20,4 @@
 #define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
 #define PGDIR_MASK	(~(PGDIR_SIZE - 1))
 
-/* Just any arbitrary offset to the start of the vmalloc VM area: the
- * current 8MB value just means that there will be a 8MB "hole" after the
- * physical memory until the kernel virtual memory starts.  That means that
- * any out-of-bounds memory accesses will hopefully be caught.
- * The vmalloc() routines leaves a hole of 4kB between each vmalloced
- * area for the same reason. ;)
- */
-#define VMALLOC_OFFSET	(8 * 1024 * 1024)
-
-#ifndef __ASSEMBLY__
-extern bool __vmalloc_start_set; /* set once high_memory is set */
-#endif
-
-#define VMALLOC_START	((unsigned long)high_memory + VMALLOC_OFFSET)
-#ifdef CONFIG_X86_PAE
-#define LAST_PKMAP 512
-#else
-#define LAST_PKMAP 1024
-#endif
-
-/*
- * This is an upper bound on sizeof(struct cpu_entry_area) / PAGE_SIZE.
- * Define this here and validate with BUILD_BUG_ON() in cpu_entry_area.c
- * to avoid include recursion hell.
- */
-#define CPU_ENTRY_AREA_PAGES	(NR_CPUS * 43)
-
-/* The +1 is for the readonly IDT page: */
-#define CPU_ENTRY_AREA_BASE	\
-	((FIXADDR_TOT_START - PAGE_SIZE*(CPU_ENTRY_AREA_PAGES+1)) & PMD_MASK)
-
-#define LDT_BASE_ADDR		\
-	((CPU_ENTRY_AREA_BASE - PAGE_SIZE) & PMD_MASK)
-
-#define LDT_END_ADDR		(LDT_BASE_ADDR + PMD_SIZE)
-
-#define PKMAP_BASE		\
-	((LDT_BASE_ADDR - PAGE_SIZE) & PMD_MASK)
-
-#ifdef CONFIG_HIGHMEM
-# define VMALLOC_END	(PKMAP_BASE - 2 * PAGE_SIZE)
-#else
-# define VMALLOC_END	(LDT_BASE_ADDR - 2 * PAGE_SIZE)
-#endif
-
-#define MODULES_VADDR	VMALLOC_START
-#define MODULES_END	VMALLOC_END
-#define MODULES_LEN	(MODULES_VADDR - MODULES_END)
-
-#define MAXMEM	(VMALLOC_END - PAGE_OFFSET - __VMALLOC_RESERVE)
-
-#endif /* _ASM_X86_PGTABLE_32_DEFS_H */
+#endif /* _ASM_X86_PGTABLE_32_TYPES_H */
diff --git a/arch/x86/include/asm/pgtable_areas.h b/arch/x86/include/asm/pgtable_areas.h
new file mode 100644
index 00000000000000..d34cce1b995cf1
--- /dev/null
+++ b/arch/x86/include/asm/pgtable_areas.h
@@ -0,0 +1,16 @@
+#ifndef _ASM_X86_PGTABLE_AREAS_H
+#define _ASM_X86_PGTABLE_AREAS_H
+
+#ifdef CONFIG_X86_32
+# include <asm/pgtable_32_areas.h>
+#endif
+
+/* Single page reserved for the readonly IDT mapping: */
+#define CPU_ENTRY_AREA_RO_IDT		CPU_ENTRY_AREA_BASE
+#define CPU_ENTRY_AREA_PER_CPU		(CPU_ENTRY_AREA_RO_IDT + PAGE_SIZE)
+
+#define CPU_ENTRY_AREA_RO_IDT_VADDR	((void *)CPU_ENTRY_AREA_RO_IDT)
+
+#define CPU_ENTRY_AREA_MAP_SIZE		(CPU_ENTRY_AREA_PER_CPU + CPU_ENTRY_AREA_ARRAY_SIZE - CPU_ENTRY_AREA_BASE)
+
+#endif /* _ASM_X86_PGTABLE_AREAS_H */
diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h
index b5e49e6bac6352..ea7400726d7a7c 100644
--- a/arch/x86/include/asm/pgtable_types.h
+++ b/arch/x86/include/asm/pgtable_types.h
@@ -110,11 +110,6 @@
 
 #define _PAGE_PROTNONE	(_AT(pteval_t, 1) << _PAGE_BIT_PROTNONE)
 
-#define _PAGE_TABLE_NOENC	(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER |\
-				 _PAGE_ACCESSED | _PAGE_DIRTY)
-#define _KERNPG_TABLE_NOENC	(_PAGE_PRESENT | _PAGE_RW |		\
-				 _PAGE_ACCESSED | _PAGE_DIRTY)
-
 /*
  * Set of bits not changed in pte_modify.  The pte's
  * protection key is treated like _PAGE_RW, for
@@ -136,80 +131,93 @@
  */
 #ifndef __ASSEMBLY__
 enum page_cache_mode {
-	_PAGE_CACHE_MODE_WB = 0,
-	_PAGE_CACHE_MODE_WC = 1,
+	_PAGE_CACHE_MODE_WB       = 0,
+	_PAGE_CACHE_MODE_WC       = 1,
 	_PAGE_CACHE_MODE_UC_MINUS = 2,
-	_PAGE_CACHE_MODE_UC = 3,
-	_PAGE_CACHE_MODE_WT = 4,
-	_PAGE_CACHE_MODE_WP = 5,
-	_PAGE_CACHE_MODE_NUM = 8
+	_PAGE_CACHE_MODE_UC       = 3,
+	_PAGE_CACHE_MODE_WT       = 4,
+	_PAGE_CACHE_MODE_WP       = 5,
+
+	_PAGE_CACHE_MODE_NUM      = 8
 };
 #endif
 
-#define _PAGE_CACHE_MASK	(_PAGE_PAT | _PAGE_PCD | _PAGE_PWT)
-#define _PAGE_NOCACHE		(cachemode2protval(_PAGE_CACHE_MODE_UC))
-#define _PAGE_CACHE_WP		(cachemode2protval(_PAGE_CACHE_MODE_WP))
+#define _PAGE_ENC		(_AT(pteval_t, sme_me_mask))
 
-#define PAGE_NONE	__pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED)
-#define PAGE_SHARED	__pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | \
-				 _PAGE_ACCESSED | _PAGE_NX)
-
-#define PAGE_SHARED_EXEC	__pgprot(_PAGE_PRESENT | _PAGE_RW |	\
-					 _PAGE_USER | _PAGE_ACCESSED)
-#define PAGE_COPY_NOEXEC	__pgprot(_PAGE_PRESENT | _PAGE_USER |	\
-					 _PAGE_ACCESSED | _PAGE_NX)
-#define PAGE_COPY_EXEC		__pgprot(_PAGE_PRESENT | _PAGE_USER |	\
-					 _PAGE_ACCESSED)
-#define PAGE_COPY		PAGE_COPY_NOEXEC
-#define PAGE_READONLY		__pgprot(_PAGE_PRESENT | _PAGE_USER |	\
-					 _PAGE_ACCESSED | _PAGE_NX)
-#define PAGE_READONLY_EXEC	__pgprot(_PAGE_PRESENT | _PAGE_USER |	\
-					 _PAGE_ACCESSED)
-
-#define __PAGE_KERNEL_EXEC						\
-	(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_GLOBAL)
-#define __PAGE_KERNEL		(__PAGE_KERNEL_EXEC | _PAGE_NX)
-
-#define __PAGE_KERNEL_RO		(__PAGE_KERNEL & ~_PAGE_RW)
-#define __PAGE_KERNEL_RX		(__PAGE_KERNEL_EXEC & ~_PAGE_RW)
-#define __PAGE_KERNEL_NOCACHE		(__PAGE_KERNEL | _PAGE_NOCACHE)
-#define __PAGE_KERNEL_VVAR		(__PAGE_KERNEL_RO | _PAGE_USER)
-#define __PAGE_KERNEL_LARGE		(__PAGE_KERNEL | _PAGE_PSE)
-#define __PAGE_KERNEL_LARGE_EXEC	(__PAGE_KERNEL_EXEC | _PAGE_PSE)
-#define __PAGE_KERNEL_WP		(__PAGE_KERNEL | _PAGE_CACHE_WP)
-
-#define __PAGE_KERNEL_IO		(__PAGE_KERNEL)
-#define __PAGE_KERNEL_IO_NOCACHE	(__PAGE_KERNEL_NOCACHE)
+#define _PAGE_CACHE_MASK	(_PAGE_PWT | _PAGE_PCD | _PAGE_PAT)
 
-#ifndef __ASSEMBLY__
+#define _PAGE_NOCACHE		(cachemode2protval(_PAGE_CACHE_MODE_UC))
+#define _PAGE_CACHE_WP		(cachemode2protval(_PAGE_CACHE_MODE_WP))
 
-#define _PAGE_ENC	(_AT(pteval_t, sme_me_mask))
+#define __PP _PAGE_PRESENT
+#define __RW _PAGE_RW
+#define _USR _PAGE_USER
+#define ___A _PAGE_ACCESSED
+#define ___D _PAGE_DIRTY
+#define ___G _PAGE_GLOBAL
+#define __NX _PAGE_NX
+
+#define _ENC _PAGE_ENC
+#define __WP _PAGE_CACHE_WP
+#define __NC _PAGE_NOCACHE
+#define _PSE _PAGE_PSE
+
+#define pgprot_val(x)		((x).pgprot)
+#define __pgprot(x)		((pgprot_t) { (x) } )
+#define __pg(x)			__pgprot(x)
+
+#define _PAGE_PAT_LARGE		(_AT(pteval_t, 1) << _PAGE_BIT_PAT_LARGE)
+
+#define PAGE_NONE	     __pg(   0|   0|   0|___A|   0|   0|   0|___G)
+#define PAGE_SHARED	     __pg(__PP|__RW|_USR|___A|__NX|   0|   0|   0)
+#define PAGE_SHARED_EXEC     __pg(__PP|__RW|_USR|___A|   0|   0|   0|   0)
+#define PAGE_COPY_NOEXEC     __pg(__PP|   0|_USR|___A|__NX|   0|   0|   0)
+#define PAGE_COPY_EXEC	     __pg(__PP|   0|_USR|___A|   0|   0|   0|   0)
+#define PAGE_COPY	     __pg(__PP|   0|_USR|___A|__NX|   0|   0|   0)
+#define PAGE_READONLY	     __pg(__PP|   0|_USR|___A|__NX|   0|   0|   0)
+#define PAGE_READONLY_EXEC   __pg(__PP|   0|_USR|___A|   0|   0|   0|   0)
+
+#define __PAGE_KERNEL		 (__PP|__RW|   0|___A|__NX|___D|   0|___G)
+#define __PAGE_KERNEL_EXEC	 (__PP|__RW|   0|___A|   0|___D|   0|___G)
+#define _KERNPG_TABLE_NOENC	 (__PP|__RW|   0|___A|   0|___D|   0|   0)
+#define _KERNPG_TABLE		 (__PP|__RW|   0|___A|   0|___D|   0|   0| _ENC)
+#define _PAGE_TABLE_NOENC	 (__PP|__RW|_USR|___A|   0|___D|   0|   0)
+#define _PAGE_TABLE		 (__PP|__RW|_USR|___A|   0|___D|   0|   0| _ENC)
+#define __PAGE_KERNEL_RO	 (__PP|   0|   0|___A|__NX|___D|   0|___G)
+#define __PAGE_KERNEL_RX	 (__PP|   0|   0|___A|   0|___D|   0|___G)
+#define __PAGE_KERNEL_NOCACHE	 (__PP|__RW|   0|___A|__NX|___D|   0|___G| __NC)
+#define __PAGE_KERNEL_VVAR	 (__PP|   0|_USR|___A|__NX|___D|   0|___G)
+#define __PAGE_KERNEL_LARGE	 (__PP|__RW|   0|___A|__NX|___D|_PSE|___G)
+#define __PAGE_KERNEL_LARGE_EXEC (__PP|__RW|   0|___A|   0|___D|_PSE|___G)
+#define __PAGE_KERNEL_WP	 (__PP|__RW|   0|___A|__NX|___D|   0|___G| __WP)
+
+
+#define __PAGE_KERNEL_IO		__PAGE_KERNEL
+#define __PAGE_KERNEL_IO_NOCACHE	__PAGE_KERNEL_NOCACHE
 
-#define _KERNPG_TABLE	(_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED |	\
-			 _PAGE_DIRTY | _PAGE_ENC)
-#define _PAGE_TABLE	(_KERNPG_TABLE | _PAGE_USER)
 
-#define __PAGE_KERNEL_ENC	(__PAGE_KERNEL | _PAGE_ENC)
-#define __PAGE_KERNEL_ENC_WP	(__PAGE_KERNEL_WP | _PAGE_ENC)
+#ifndef __ASSEMBLY__
 
-#define __PAGE_KERNEL_NOENC	(__PAGE_KERNEL)
-#define __PAGE_KERNEL_NOENC_WP	(__PAGE_KERNEL_WP)
+#define __PAGE_KERNEL_ENC	(__PAGE_KERNEL    | _ENC)
+#define __PAGE_KERNEL_ENC_WP	(__PAGE_KERNEL_WP | _ENC)
+#define __PAGE_KERNEL_NOENC	(__PAGE_KERNEL    |    0)
+#define __PAGE_KERNEL_NOENC_WP	(__PAGE_KERNEL_WP |    0)
 
-#define default_pgprot(x)	__pgprot((x) & __default_kernel_pte_mask)
+#define __pgprot_mask(x)	__pgprot((x) & __default_kernel_pte_mask)
 
-#define PAGE_KERNEL		default_pgprot(__PAGE_KERNEL | _PAGE_ENC)
-#define PAGE_KERNEL_NOENC	default_pgprot(__PAGE_KERNEL)
-#define PAGE_KERNEL_RO		default_pgprot(__PAGE_KERNEL_RO | _PAGE_ENC)
-#define PAGE_KERNEL_EXEC	default_pgprot(__PAGE_KERNEL_EXEC | _PAGE_ENC)
-#define PAGE_KERNEL_EXEC_NOENC	default_pgprot(__PAGE_KERNEL_EXEC)
-#define PAGE_KERNEL_RX		default_pgprot(__PAGE_KERNEL_RX | _PAGE_ENC)
-#define PAGE_KERNEL_NOCACHE	default_pgprot(__PAGE_KERNEL_NOCACHE | _PAGE_ENC)
-#define PAGE_KERNEL_LARGE	default_pgprot(__PAGE_KERNEL_LARGE | _PAGE_ENC)
-#define PAGE_KERNEL_LARGE_EXEC	default_pgprot(__PAGE_KERNEL_LARGE_EXEC | _PAGE_ENC)
-#define PAGE_KERNEL_VVAR	default_pgprot(__PAGE_KERNEL_VVAR | _PAGE_ENC)
+#define PAGE_KERNEL		__pgprot_mask(__PAGE_KERNEL            | _ENC)
+#define PAGE_KERNEL_NOENC	__pgprot_mask(__PAGE_KERNEL            |    0)
+#define PAGE_KERNEL_RO		__pgprot_mask(__PAGE_KERNEL_RO         | _ENC)
+#define PAGE_KERNEL_EXEC	__pgprot_mask(__PAGE_KERNEL_EXEC       | _ENC)
+#define PAGE_KERNEL_EXEC_NOENC	__pgprot_mask(__PAGE_KERNEL_EXEC       |    0)
+#define PAGE_KERNEL_RX		__pgprot_mask(__PAGE_KERNEL_RX         | _ENC)
+#define PAGE_KERNEL_NOCACHE	__pgprot_mask(__PAGE_KERNEL_NOCACHE    | _ENC)
+#define PAGE_KERNEL_LARGE	__pgprot_mask(__PAGE_KERNEL_LARGE      | _ENC)
+#define PAGE_KERNEL_LARGE_EXEC	__pgprot_mask(__PAGE_KERNEL_LARGE_EXEC | _ENC)
+#define PAGE_KERNEL_VVAR	__pgprot_mask(__PAGE_KERNEL_VVAR       | _ENC)
 
-#define PAGE_KERNEL_IO		default_pgprot(__PAGE_KERNEL_IO)
-#define PAGE_KERNEL_IO_NOCACHE	default_pgprot(__PAGE_KERNEL_IO_NOCACHE)
+#define PAGE_KERNEL_IO		__pgprot_mask(__PAGE_KERNEL_IO)
+#define PAGE_KERNEL_IO_NOCACHE	__pgprot_mask(__PAGE_KERNEL_IO_NOCACHE)
 
 #endif	/* __ASSEMBLY__ */
 
@@ -449,9 +457,6 @@ static inline pteval_t pte_flags(pte_t pte)
 	return native_pte_val(pte) & PTE_FLAGS_MASK;
 }
 
-#define pgprot_val(x)	((x).pgprot)
-#define __pgprot(x)	((pgprot_t) { (x) } )
-
 extern uint16_t __cachemode2pte_tbl[_PAGE_CACHE_MODE_NUM];
 extern uint8_t __pte2cachemode_tbl[8];
 
diff --git a/arch/x86/include/asm/vmalloc.h b/arch/x86/include/asm/vmalloc.h
new file mode 100644
index 00000000000000..29837740b52092
--- /dev/null
+++ b/arch/x86/include/asm/vmalloc.h
@@ -0,0 +1,6 @@
+#ifndef _ASM_X86_VMALLOC_H
+#define _ASM_X86_VMALLOC_H
+
+#include <asm/pgtable_areas.h>
+
+#endif /* _ASM_X86_VMALLOC_H */
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 2e4d90294fe67c..9d6a35a4586e90 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -49,7 +49,7 @@
 #include <asm/cpu.h>
 #include <asm/mce.h>
 #include <asm/msr.h>
-#include <asm/pat.h>
+#include <asm/memtype.h>
 #include <asm/microcode.h>
 #include <asm/microcode_intel.h>
 #include <asm/intel-family.h>
diff --git a/arch/x86/kernel/cpu/mtrr/generic.c b/arch/x86/kernel/cpu/mtrr/generic.c
index aa5c064a6a227f..51b9190c628b22 100644
--- a/arch/x86/kernel/cpu/mtrr/generic.c
+++ b/arch/x86/kernel/cpu/mtrr/generic.c
@@ -15,7 +15,7 @@
 #include <asm/tlbflush.h>
 #include <asm/mtrr.h>
 #include <asm/msr.h>
-#include <asm/pat.h>
+#include <asm/memtype.h>
 
 #include "mtrr.h"
 
diff --git a/arch/x86/kernel/cpu/mtrr/mtrr.c b/arch/x86/kernel/cpu/mtrr/mtrr.c
index 507039c20128a6..6a80f36b5d598a 100644
--- a/arch/x86/kernel/cpu/mtrr/mtrr.c
+++ b/arch/x86/kernel/cpu/mtrr/mtrr.c
@@ -52,7 +52,7 @@
 #include <asm/e820/api.h>
 #include <asm/mtrr.h>
 #include <asm/msr.h>
-#include <asm/pat.h>
+#include <asm/memtype.h>
 
 #include "mtrr.h"
 
diff --git a/arch/x86/kernel/cpu/scattered.c b/arch/x86/kernel/cpu/scattered.c
index adf9b71386effa..62b137c3c97a20 100644
--- a/arch/x86/kernel/cpu/scattered.c
+++ b/arch/x86/kernel/cpu/scattered.c
@@ -4,7 +4,7 @@
  */
 #include <linux/cpu.h>
 
-#include <asm/pat.h>
+#include <asm/memtype.h>
 #include <asm/apic.h>
 #include <asm/processor.h>
 
diff --git a/arch/x86/kernel/cpu/topology.c b/arch/x86/kernel/cpu/topology.c
index ee48c3fc8a65e2..d3a0791bc052ad 100644
--- a/arch/x86/kernel/cpu/topology.c
+++ b/arch/x86/kernel/cpu/topology.c
@@ -7,7 +7,7 @@
 
 #include <linux/cpu.h>
 #include <asm/apic.h>
-#include <asm/pat.h>
+#include <asm/memtype.h>
 #include <asm/processor.h>
 
 #include "cpu.h"
diff --git a/arch/x86/kernel/ldt.c b/arch/x86/kernel/ldt.c
index b2463fcb20a811..c57e1ca70fd100 100644
--- a/arch/x86/kernel/ldt.c
+++ b/arch/x86/kernel/ldt.c
@@ -28,6 +28,89 @@
 #include <asm/desc.h>
 #include <asm/mmu_context.h>
 #include <asm/syscalls.h>
+#include <asm/pgtable_areas.h>
+
+/* This is a multiple of PAGE_SIZE. */
+#define LDT_SLOT_STRIDE (LDT_ENTRIES * LDT_ENTRY_SIZE)
+
+static inline void *ldt_slot_va(int slot)
+{
+	return (void *)(LDT_BASE_ADDR + LDT_SLOT_STRIDE * slot);
+}
+
+void load_mm_ldt(struct mm_struct *mm)
+{
+	struct ldt_struct *ldt;
+
+	/* READ_ONCE synchronizes with smp_store_release */
+	ldt = READ_ONCE(mm->context.ldt);
+
+	/*
+	 * Any change to mm->context.ldt is followed by an IPI to all
+	 * CPUs with the mm active.  The LDT will not be freed until
+	 * after the IPI is handled by all such CPUs.  This means that,
+	 * if the ldt_struct changes before we return, the values we see
+	 * will be safe, and the new values will be loaded before we run
+	 * any user code.
+	 *
+	 * NB: don't try to convert this to use RCU without extreme care.
+	 * We would still need IRQs off, because we don't want to change
+	 * the local LDT after an IPI loaded a newer value than the one
+	 * that we can see.
+	 */
+
+	if (unlikely(ldt)) {
+		if (static_cpu_has(X86_FEATURE_PTI)) {
+			if (WARN_ON_ONCE((unsigned long)ldt->slot > 1)) {
+				/*
+				 * Whoops -- either the new LDT isn't mapped
+				 * (if slot == -1) or is mapped into a bogus
+				 * slot (if slot > 1).
+				 */
+				clear_LDT();
+				return;
+			}
+
+			/*
+			 * If page table isolation is enabled, ldt->entries
+			 * will not be mapped in the userspace pagetables.
+			 * Tell the CPU to access the LDT through the alias
+			 * at ldt_slot_va(ldt->slot).
+			 */
+			set_ldt(ldt_slot_va(ldt->slot), ldt->nr_entries);
+		} else {
+			set_ldt(ldt->entries, ldt->nr_entries);
+		}
+	} else {
+		clear_LDT();
+	}
+}
+
+void switch_ldt(struct mm_struct *prev, struct mm_struct *next)
+{
+	/*
+	 * Load the LDT if either the old or new mm had an LDT.
+	 *
+	 * An mm will never go from having an LDT to not having an LDT.  Two
+	 * mms never share an LDT, so we don't gain anything by checking to
+	 * see whether the LDT changed.  There's also no guarantee that
+	 * prev->context.ldt actually matches LDTR, but, if LDTR is non-NULL,
+	 * then prev->context.ldt will also be non-NULL.
+	 *
+	 * If we really cared, we could optimize the case where prev == next
+	 * and we're exiting lazy mode.  Most of the time, if this happens,
+	 * we don't actually need to reload LDTR, but modify_ldt() is mostly
+	 * used by legacy code and emulators where we don't need this level of
+	 * performance.
+	 *
+	 * This uses | instead of || because it generates better code.
+	 */
+	if (unlikely((unsigned long)prev->context.ldt |
+		     (unsigned long)next->context.ldt))
+		load_mm_ldt(next);
+
+	DEBUG_LOCKS_WARN_ON(preemptible());
+}
 
 static void refresh_ldt_segments(void)
 {
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index cedfe2077a69bf..90296a04e5adcc 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -2,130 +2,53 @@
 /*
  *  Copyright (C) 1995  Linus Torvalds
  *
- *  Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999
- *
- *  Memory region support
- *	David Parsons <orc@pell.chi.il.us>, July-August 1999
- *
- *  Added E820 sanitization routine (removes overlapping memory regions);
- *  Brian Moyle <bmoyle@mvista.com>, February 2001
- *
- * Moved CPU detection code to cpu/${cpu}.c
- *    Patrick Mochel <mochel@osdl.org>, March 2002
- *
- *  Provisions for empty E820 memory regions (reported by certain BIOSes).
- *  Alex Achenbach <xela@slit.de>, December 2002.
- *
- */
-
-/*
- * This file handles the architecture-dependent parts of initialization
+ * This file contains the setup_arch() code, which handles the architecture-dependent
+ * parts of early kernel initialization.
  */
-
-#include <linux/sched.h>
-#include <linux/mm.h>
-#include <linux/mmzone.h>
-#include <linux/screen_info.h>
-#include <linux/ioport.h>
-#include <linux/acpi.h>
-#include <linux/sfi.h>
-#include <linux/apm_bios.h>
-#include <linux/initrd.h>
-#include <linux/memblock.h>
-#include <linux/seq_file.h>
 #include <linux/console.h>
-#include <linux/root_dev.h>
-#include <linux/highmem.h>
-#include <linux/export.h>
+#include <linux/crash_dump.h>
+#include <linux/dmi.h>
 #include <linux/efi.h>
-#include <linux/init.h>
-#include <linux/edd.h>
+#include <linux/init_ohci1394_dma.h>
+#include <linux/initrd.h>
 #include <linux/iscsi_ibft.h>
-#include <linux/nodemask.h>
-#include <linux/kexec.h>
-#include <linux/dmi.h>
-#include <linux/pfn.h>
+#include <linux/memblock.h>
 #include <linux/pci.h>
-#include <asm/pci-direct.h>
-#include <linux/init_ohci1394_dma.h>
-#include <linux/kvm_para.h>
-#include <linux/dma-contiguous.h>
-#include <xen/xen.h>
-#include <uapi/linux/mount.h>
-
-#include <linux/errno.h>
-#include <linux/kernel.h>
-#include <linux/stddef.h>
-#include <linux/unistd.h>
-#include <linux/ptrace.h>
-#include <linux/user.h>
-#include <linux/delay.h>
-
-#include <linux/kallsyms.h>
-#include <linux/cpufreq.h>
-#include <linux/dma-mapping.h>
-#include <linux/ctype.h>
-#include <linux/uaccess.h>
-
-#include <linux/percpu.h>
-#include <linux/crash_dump.h>
+#include <linux/root_dev.h>
+#include <linux/sfi.h>
 #include <linux/tboot.h>
-#include <linux/jiffies.h>
-#include <linux/mem_encrypt.h>
-#include <linux/sizes.h>
-
 #include <linux/usb/xhci-dbgp.h>
-#include <video/edid.h>
 
-#include <asm/mtrr.h>
+#include <uapi/linux/mount.h>
+
+#include <xen/xen.h>
+
 #include <asm/apic.h>
-#include <asm/realmode.h>
-#include <asm/e820/api.h>
-#include <asm/mpspec.h>
-#include <asm/setup.h>
-#include <asm/efi.h>
-#include <asm/timer.h>
-#include <asm/i8259.h>
-#include <asm/sections.h>
-#include <asm/io_apic.h>
-#include <asm/ist.h>
-#include <asm/setup_arch.h>
 #include <asm/bios_ebda.h>
-#include <asm/cacheflush.h>
-#include <asm/processor.h>
 #include <asm/bugs.h>
-#include <asm/kasan.h>
-
-#include <asm/vsyscall.h>
 #include <asm/cpu.h>
-#include <asm/desc.h>
-#include <asm/dma.h>
-#include <asm/iommu.h>
+#include <asm/efi.h>
 #include <asm/gart.h>
-#include <asm/mmu_context.h>
-#include <asm/proto.h>
-
-#include <asm/paravirt.h>
 #include <asm/hypervisor.h>
-#include <asm/olpc_ofw.h>
-
-#include <asm/percpu.h>
-#include <asm/topology.h>
-#include <asm/apicdef.h>
-#include <asm/amd_nb.h>
+#include <asm/io_apic.h>
+#include <asm/kasan.h>
+#include <asm/kaslr.h>
 #include <asm/mce.h>
-#include <asm/alternative.h>
+#include <asm/mtrr.h>
+#include <asm/olpc_ofw.h>
+#include <asm/pci-direct.h>
 #include <asm/prom.h>
-#include <asm/microcode.h>
-#include <asm/kaslr.h>
+#include <asm/proto.h>
 #include <asm/unwind.h>
+#include <asm/vsyscall.h>
+#include <linux/vmalloc.h>
 
 /*
- * max_low_pfn_mapped: highest direct mapped pfn under 4GB
- * max_pfn_mapped:     highest direct mapped pfn over 4GB
+ * max_low_pfn_mapped: highest directly mapped pfn < 4 GB
+ * max_pfn_mapped:     highest directly mapped pfn > 4 GB
  *
  * The direct mapping only covers E820_TYPE_RAM regions, so the ranges and gaps are
- * represented by pfn_mapped
+ * represented by pfn_mapped[].
  */
 unsigned long max_low_pfn_mapped;
 unsigned long max_pfn_mapped;
@@ -135,14 +58,23 @@ RESERVE_BRK(dmi_alloc, 65536);
 #endif
 
 
-static __initdata unsigned long _brk_start = (unsigned long)__brk_base;
-unsigned long _brk_end = (unsigned long)__brk_base;
+/*
+ * Range of the BSS area. The size of the BSS area is determined
+ * at link time, with RESERVE_BRK*() facility reserving additional
+ * chunks.
+ */
+static __initdata
+unsigned long _brk_start = (unsigned long)__brk_base;
+unsigned long _brk_end   = (unsigned long)__brk_base;
 
 struct boot_params boot_params;
 
 /*
- * Machine setup..
+ * These are the four main kernel memory regions, we put them into
+ * the resource tree so that kdump tools and other debugging tools
+ * recover it:
  */
+
 static struct resource rodata_resource = {
 	.name	= "Kernel rodata",
 	.start	= 0,
@@ -173,16 +105,16 @@ static struct resource bss_resource = {
 
 
 #ifdef CONFIG_X86_32
-/* cpu data as detected by the assembly code in head_32.S */
+/* CPU data as detected by the assembly code in head_32.S */
 struct cpuinfo_x86 new_cpu_data;
 
-/* common cpu data for all cpus */
+/* Common CPU data for all CPUs */
 struct cpuinfo_x86 boot_cpu_data __read_mostly;
 EXPORT_SYMBOL(boot_cpu_data);
 
 unsigned int def_to_bigsmp;
 
-/* for MCA, but anyone else can use it if they want */
+/* For MCA, but anyone else can use it if they want */
 unsigned int machine_id;
 unsigned int machine_submodel_id;
 unsigned int BIOS_revision;
@@ -468,15 +400,15 @@ static void __init memblock_x86_reserve_range_setup_data(void)
 /*
  * Keep the crash kernel below this limit.
  *
- * On 32 bits earlier kernels would limit the kernel to the low 512 MiB
+ * Earlier 32-bits kernels would limit the kernel to the low 512 MB range
  * due to mapping restrictions.
  *
- * On 64bit, kdump kernel need be restricted to be under 64TB, which is
+ * 64-bit kdump kernels need to be restricted to be under 64 TB, which is
  * the upper limit of system RAM in 4-level paging mode. Since the kdump
- * jumping could be from 5-level to 4-level, the jumping will fail if
- * kernel is put above 64TB, and there's no way to detect the paging mode
- * of the kernel which will be loaded for dumping during the 1st kernel
- * bootup.
+ * jump could be from 5-level paging to 4-level paging, the jump will fail if
+ * the kernel is put above 64 TB, and during the 1st kernel bootup there's
+ * no good way to detect the paging mode of the target kernel which will be
+ * loaded for dumping.
  */
 #ifdef CONFIG_X86_32
 # define CRASH_ADDR_LOW_MAX	SZ_512M
@@ -887,7 +819,7 @@ void __init setup_arch(char **cmdline_p)
 	/*
 	 * Note: Quark X1000 CPUs advertise PGE incorrectly and require
 	 * a cr3 based tlb flush, so the following __flush_tlb_all()
-	 * will not flush anything because the cpu quirk which clears
+	 * will not flush anything because the CPU quirk which clears
 	 * X86_FEATURE_PGE has not been invoked yet. Though due to the
 	 * load_cr3() above the TLB has been flushed already. The
 	 * quirk is invoked before subsequent calls to __flush_tlb_all()
diff --git a/arch/x86/kernel/x86_init.c b/arch/x86/kernel/x86_init.c
index ce89430a7f8011..23e25f3034c2d4 100644
--- a/arch/x86/kernel/x86_init.c
+++ b/arch/x86/kernel/x86_init.c
@@ -20,7 +20,7 @@
 #include <asm/irq.h>
 #include <asm/io_apic.h>
 #include <asm/hpet.h>
-#include <asm/pat.h>
+#include <asm/memtype.h>
 #include <asm/tsc.h>
 #include <asm/iommu.h>
 #include <asm/mach_traps.h>
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 6f92b40d798cab..a32b847a8089dd 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -40,7 +40,7 @@
 #include <linux/kthread.h>
 
 #include <asm/page.h>
-#include <asm/pat.h>
+#include <asm/memtype.h>
 #include <asm/cmpxchg.h>
 #include <asm/e820/api.h>
 #include <asm/io.h>
diff --git a/arch/x86/mm/Makefile b/arch/x86/mm/Makefile
index 3b89c201ac267d..345848f270e3b4 100644
--- a/arch/x86/mm/Makefile
+++ b/arch/x86/mm/Makefile
@@ -12,8 +12,10 @@ CFLAGS_REMOVE_mem_encrypt.o		= -pg
 CFLAGS_REMOVE_mem_encrypt_identity.o	= -pg
 endif
 
-obj-y	:=  init.o init_$(BITS).o fault.o ioremap.o extable.o pageattr.o mmap.o \
-	    pat.o pgtable.o physaddr.o setup_nx.o tlb.o cpu_entry_area.o maccess.o
+obj-y				:=  init.o init_$(BITS).o fault.o ioremap.o extable.o mmap.o \
+				    pgtable.o physaddr.o setup_nx.o tlb.o cpu_entry_area.o maccess.o
+
+obj-y				+= pat/
 
 # Make sure __phys_addr has no stackprotector
 nostackp := $(call cc-option, -fno-stack-protector)
@@ -23,8 +25,6 @@ CFLAGS_mem_encrypt_identity.o	:= $(nostackp)
 
 CFLAGS_fault.o := -I $(srctree)/$(src)/../include/asm/trace
 
-obj-$(CONFIG_X86_PAT)		+= pat_interval.o
-
 obj-$(CONFIG_X86_32)		+= pgtable_32.o iomap_32.o
 
 obj-$(CONFIG_HUGETLB_PAGE)	+= hugetlbpage.o
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index 304d31d8cbbc5c..c9c8523a3a480d 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -29,6 +29,7 @@
 #include <asm/efi.h>			/* efi_recover_from_page_fault()*/
 #include <asm/desc.h>			/* store_idt(), ...		*/
 #include <asm/cpu_entry_area.h>		/* exception stack		*/
+#include <asm/pgtable_areas.h>		/* VMALLOC_START, ...		*/
 
 #define CREATE_TRACE_POINTS
 #include <asm/trace/exceptions.h>
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 0a74407ef92ea9..8d29ae8d3eb7e0 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -52,6 +52,7 @@
 #include <asm/page_types.h>
 #include <asm/cpu_entry_area.h>
 #include <asm/init.h>
+#include <asm/pgtable_areas.h>
 
 #include "mm_internal.h"
 
diff --git a/arch/x86/mm/iomap_32.c b/arch/x86/mm/iomap_32.c
index 6748b4c2baff32..f60398aeb6445f 100644
--- a/arch/x86/mm/iomap_32.c
+++ b/arch/x86/mm/iomap_32.c
@@ -4,7 +4,7 @@
  */
 
 #include <asm/iomap.h>
-#include <asm/pat.h>
+#include <asm/memtype.h>
 #include <linux/export.h>
 #include <linux/highmem.h>
 
@@ -26,7 +26,7 @@ int iomap_create_wc(resource_size_t base, unsigned long size, pgprot_t *prot)
 	if (!is_io_mapping_possible(base, size))
 		return -EINVAL;
 
-	ret = io_reserve_memtype(base, base + size, &pcm);
+	ret = memtype_reserve_io(base, base + size, &pcm);
 	if (ret)
 		return ret;
 
@@ -40,7 +40,7 @@ EXPORT_SYMBOL_GPL(iomap_create_wc);
 
 void iomap_free(resource_size_t base, unsigned long size)
 {
-	io_free_memtype(base, base + size);
+	memtype_free_io(base, base + size);
 }
 EXPORT_SYMBOL_GPL(iomap_free);
 
diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index b3a2936377b56b..44e4beb4239f93 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -24,7 +24,7 @@
 #include <asm/pgtable.h>
 #include <asm/tlbflush.h>
 #include <asm/pgalloc.h>
-#include <asm/pat.h>
+#include <asm/memtype.h>
 #include <asm/setup.h>
 
 #include "physaddr.h"
@@ -196,10 +196,10 @@ __ioremap_caller(resource_size_t phys_addr, unsigned long size,
 	phys_addr &= PHYSICAL_PAGE_MASK;
 	size = PAGE_ALIGN(last_addr+1) - phys_addr;
 
-	retval = reserve_memtype(phys_addr, (u64)phys_addr + size,
+	retval = memtype_reserve(phys_addr, (u64)phys_addr + size,
 						pcm, &new_pcm);
 	if (retval) {
-		printk(KERN_ERR "ioremap reserve_memtype failed %d\n", retval);
+		printk(KERN_ERR "ioremap memtype_reserve failed %d\n", retval);
 		return NULL;
 	}
 
@@ -255,7 +255,7 @@ __ioremap_caller(resource_size_t phys_addr, unsigned long size,
 	area->phys_addr = phys_addr;
 	vaddr = (unsigned long) area->addr;
 
-	if (kernel_map_sync_memtype(phys_addr, size, pcm))
+	if (memtype_kernel_map_sync(phys_addr, size, pcm))
 		goto err_free_area;
 
 	if (ioremap_page_range(vaddr, vaddr + size, phys_addr, prot))
@@ -275,7 +275,7 @@ __ioremap_caller(resource_size_t phys_addr, unsigned long size,
 err_free_area:
 	free_vm_area(area);
 err_free_memtype:
-	free_memtype(phys_addr, phys_addr + size);
+	memtype_free(phys_addr, phys_addr + size);
 	return NULL;
 }
 
@@ -451,7 +451,7 @@ void iounmap(volatile void __iomem *addr)
 		return;
 	}
 
-	free_memtype(p->phys_addr, p->phys_addr + get_vm_area_size(p));
+	memtype_free(p->phys_addr, p->phys_addr + get_vm_area_size(p));
 
 	/* Finally remove it */
 	o = remove_vm_area((void __force *)addr);
diff --git a/arch/x86/mm/pat/Makefile b/arch/x86/mm/pat/Makefile
new file mode 100644
index 00000000000000..ea464c995161dc
--- /dev/null
+++ b/arch/x86/mm/pat/Makefile
@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0
+
+obj-y				:= set_memory.o memtype.o
+
+obj-$(CONFIG_X86_PAT)		+= memtype_interval.o
diff --git a/arch/x86/mm/pageattr-test.c b/arch/x86/mm/pat/cpa-test.c
similarity index 100%
rename from arch/x86/mm/pageattr-test.c
rename to arch/x86/mm/pat/cpa-test.c
diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat/memtype.c
similarity index 84%
rename from arch/x86/mm/pat.c
rename to arch/x86/mm/pat/memtype.c
index 2d758e19ef22d4..394be8611748ad 100644
--- a/arch/x86/mm/pat.c
+++ b/arch/x86/mm/pat/memtype.c
@@ -1,11 +1,34 @@
 // SPDX-License-Identifier: GPL-2.0-only
 /*
- * Handle caching attributes in page tables (PAT)
+ * Page Attribute Table (PAT) support: handle memory caching attributes in page tables.
  *
  * Authors: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
  *          Suresh B Siddha <suresh.b.siddha@intel.com>
  *
  * Loosely based on earlier PAT patchset from Eric Biederman and Andi Kleen.
+ *
+ * Basic principles:
+ *
+ * PAT is a CPU feature supported by all modern x86 CPUs, to allow the firmware and
+ * the kernel to set one of a handful of 'caching type' attributes for physical
+ * memory ranges: uncached, write-combining, write-through, write-protected,
+ * and the most commonly used and default attribute: write-back caching.
+ *
+ * PAT support supercedes and augments MTRR support in a compatible fashion: MTRR is
+ * a hardware interface to enumerate a limited number of physical memory ranges
+ * and set their caching attributes explicitly, programmed into the CPU via MSRs.
+ * Even modern CPUs have MTRRs enabled - but these are typically not touched
+ * by the kernel or by user-space (such as the X server), we rely on PAT for any
+ * additional cache attribute logic.
+ *
+ * PAT doesn't work via explicit memory ranges, but uses page table entries to add
+ * cache attribute information to the mapped memory range: there's 3 bits used,
+ * (_PAGE_PWT, _PAGE_PCD, _PAGE_PAT), with the 8 possible values mapped by the
+ * CPU to actual cache attributes via an MSR loaded into the CPU (MSR_IA32_CR_PAT).
+ *
+ * ( There's a metric ton of finer details, such as compatibility with CPU quirks
+ *   that only support 4 types of PAT entries, and interaction with MTRRs, see
+ *   below for details. )
  */
 
 #include <linux/seq_file.h>
@@ -29,44 +52,48 @@
 #include <asm/mtrr.h>
 #include <asm/page.h>
 #include <asm/msr.h>
-#include <asm/pat.h>
+#include <asm/memtype.h>
 #include <asm/io.h>
 
-#include "pat_internal.h"
-#include "mm_internal.h"
+#include "memtype.h"
+#include "../mm_internal.h"
 
 #undef pr_fmt
 #define pr_fmt(fmt) "" fmt
 
-static bool __read_mostly boot_cpu_done;
+static bool __read_mostly pat_bp_initialized;
 static bool __read_mostly pat_disabled = !IS_ENABLED(CONFIG_X86_PAT);
-static bool __read_mostly pat_initialized;
-static bool __read_mostly init_cm_done;
+static bool __read_mostly pat_bp_enabled;
+static bool __read_mostly pat_cm_initialized;
 
-void pat_disable(const char *reason)
+/*
+ * PAT support is enabled by default, but can be disabled for
+ * various user-requested or hardware-forced reasons:
+ */
+void pat_disable(const char *msg_reason)
 {
 	if (pat_disabled)
 		return;
 
-	if (boot_cpu_done) {
+	if (pat_bp_initialized) {
 		WARN_ONCE(1, "x86/PAT: PAT cannot be disabled after initialization\n");
 		return;
 	}
 
 	pat_disabled = true;
-	pr_info("x86/PAT: %s\n", reason);
+	pr_info("x86/PAT: %s\n", msg_reason);
 }
 
 static int __init nopat(char *str)
 {
-	pat_disable("PAT support disabled.");
+	pat_disable("PAT support disabled via boot option.");
 	return 0;
 }
 early_param("nopat", nopat);
 
 bool pat_enabled(void)
 {
-	return pat_initialized;
+	return pat_bp_enabled;
 }
 EXPORT_SYMBOL_GPL(pat_enabled);
 
@@ -197,6 +224,8 @@ static void __init_cache_modes(u64 pat)
 	char pat_msg[33];
 	int i;
 
+	WARN_ON_ONCE(pat_cm_initialized);
+
 	pat_msg[32] = 0;
 	for (i = 7; i >= 0; i--) {
 		cache = pat_get_cache_mode((pat >> (i * 8)) & 7,
@@ -205,28 +234,28 @@ static void __init_cache_modes(u64 pat)
 	}
 	pr_info("x86/PAT: Configuration [0-7]: %s\n", pat_msg);
 
-	init_cm_done = true;
+	pat_cm_initialized = true;
 }
 
 #define PAT(x, y)	((u64)PAT_ ## y << ((x)*8))
 
-static void pat_bsp_init(u64 pat)
+static void pat_bp_init(u64 pat)
 {
 	u64 tmp_pat;
 
 	if (!boot_cpu_has(X86_FEATURE_PAT)) {
-		pat_disable("PAT not supported by CPU.");
+		pat_disable("PAT not supported by the CPU.");
 		return;
 	}
 
 	rdmsrl(MSR_IA32_CR_PAT, tmp_pat);
 	if (!tmp_pat) {
-		pat_disable("PAT MSR is 0, disabled.");
+		pat_disable("PAT support disabled by the firmware.");
 		return;
 	}
 
 	wrmsrl(MSR_IA32_CR_PAT, pat);
-	pat_initialized = true;
+	pat_bp_enabled = true;
 
 	__init_cache_modes(pat);
 }
@@ -248,7 +277,7 @@ void init_cache_modes(void)
 {
 	u64 pat = 0;
 
-	if (init_cm_done)
+	if (pat_cm_initialized)
 		return;
 
 	if (boot_cpu_has(X86_FEATURE_PAT)) {
@@ -291,7 +320,7 @@ void init_cache_modes(void)
 }
 
 /**
- * pat_init - Initialize PAT MSR and PAT table
+ * pat_init - Initialize the PAT MSR and PAT table on the current CPU
  *
  * This function initializes PAT MSR and PAT table with an OS-defined value
  * to enable additional cache attributes, WC, WT and WP.
@@ -305,6 +334,10 @@ void pat_init(void)
 	u64 pat;
 	struct cpuinfo_x86 *c = &boot_cpu_data;
 
+#ifndef CONFIG_X86_PAT
+	pr_info_once("x86/PAT: PAT support disabled because CONFIG_X86_PAT is disabled in the kernel.\n");
+#endif
+
 	if (pat_disabled)
 		return;
 
@@ -364,9 +397,9 @@ void pat_init(void)
 		      PAT(4, WB) | PAT(5, WP) | PAT(6, UC_MINUS) | PAT(7, WT);
 	}
 
-	if (!boot_cpu_done) {
-		pat_bsp_init(pat);
-		boot_cpu_done = true;
+	if (!pat_bp_initialized) {
+		pat_bp_init(pat);
+		pat_bp_initialized = true;
 	} else {
 		pat_ap_init(pat);
 	}
@@ -542,10 +575,10 @@ static u64 sanitize_phys(u64 address)
  * available type in new_type in case of no error. In case of any error
  * it will return a negative return value.
  */
-int reserve_memtype(u64 start, u64 end, enum page_cache_mode req_type,
+int memtype_reserve(u64 start, u64 end, enum page_cache_mode req_type,
 		    enum page_cache_mode *new_type)
 {
-	struct memtype *new;
+	struct memtype *entry_new;
 	enum page_cache_mode actual_type;
 	int is_range_ram;
 	int err = 0;
@@ -593,22 +626,22 @@ int reserve_memtype(u64 start, u64 end, enum page_cache_mode req_type,
 		return -EINVAL;
 	}
 
-	new  = kzalloc(sizeof(struct memtype), GFP_KERNEL);
-	if (!new)
+	entry_new = kzalloc(sizeof(struct memtype), GFP_KERNEL);
+	if (!entry_new)
 		return -ENOMEM;
 
-	new->start	= start;
-	new->end	= end;
-	new->type	= actual_type;
+	entry_new->start = start;
+	entry_new->end	 = end;
+	entry_new->type	 = actual_type;
 
 	spin_lock(&memtype_lock);
 
-	err = memtype_check_insert(new, new_type);
+	err = memtype_check_insert(entry_new, new_type);
 	if (err) {
-		pr_info("x86/PAT: reserve_memtype failed [mem %#010Lx-%#010Lx], track %s, req %s\n",
+		pr_info("x86/PAT: memtype_reserve failed [mem %#010Lx-%#010Lx], track %s, req %s\n",
 			start, end - 1,
-			cattr_name(new->type), cattr_name(req_type));
-		kfree(new);
+			cattr_name(entry_new->type), cattr_name(req_type));
+		kfree(entry_new);
 		spin_unlock(&memtype_lock);
 
 		return err;
@@ -616,18 +649,17 @@ int reserve_memtype(u64 start, u64 end, enum page_cache_mode req_type,
 
 	spin_unlock(&memtype_lock);
 
-	dprintk("reserve_memtype added [mem %#010Lx-%#010Lx], track %s, req %s, ret %s\n",
-		start, end - 1, cattr_name(new->type), cattr_name(req_type),
+	dprintk("memtype_reserve added [mem %#010Lx-%#010Lx], track %s, req %s, ret %s\n",
+		start, end - 1, cattr_name(entry_new->type), cattr_name(req_type),
 		new_type ? cattr_name(*new_type) : "-");
 
 	return err;
 }
 
-int free_memtype(u64 start, u64 end)
+int memtype_free(u64 start, u64 end)
 {
-	int err = -EINVAL;
 	int is_range_ram;
-	struct memtype *entry;
+	struct memtype *entry_old;
 
 	if (!pat_enabled())
 		return 0;
@@ -640,28 +672,24 @@ int free_memtype(u64 start, u64 end)
 		return 0;
 
 	is_range_ram = pat_pagerange_is_ram(start, end);
-	if (is_range_ram == 1) {
-
-		err = free_ram_pages_type(start, end);
-
-		return err;
-	} else if (is_range_ram < 0) {
+	if (is_range_ram == 1)
+		return free_ram_pages_type(start, end);
+	if (is_range_ram < 0)
 		return -EINVAL;
-	}
 
 	spin_lock(&memtype_lock);
-	entry = memtype_erase(start, end);
+	entry_old = memtype_erase(start, end);
 	spin_unlock(&memtype_lock);
 
-	if (IS_ERR(entry)) {
+	if (IS_ERR(entry_old)) {
 		pr_info("x86/PAT: %s:%d freeing invalid memtype [mem %#010Lx-%#010Lx]\n",
 			current->comm, current->pid, start, end - 1);
 		return -EINVAL;
 	}
 
-	kfree(entry);
+	kfree(entry_old);
 
-	dprintk("free_memtype request [mem %#010Lx-%#010Lx]\n", start, end - 1);
+	dprintk("memtype_free request [mem %#010Lx-%#010Lx]\n", start, end - 1);
 
 	return 0;
 }
@@ -700,6 +728,7 @@ static enum page_cache_mode lookup_memtype(u64 paddr)
 		rettype = _PAGE_CACHE_MODE_UC_MINUS;
 
 	spin_unlock(&memtype_lock);
+
 	return rettype;
 }
 
@@ -723,7 +752,7 @@ bool pat_pfn_immune_to_uc_mtrr(unsigned long pfn)
 EXPORT_SYMBOL_GPL(pat_pfn_immune_to_uc_mtrr);
 
 /**
- * io_reserve_memtype - Request a memory type mapping for a region of memory
+ * memtype_reserve_io - Request a memory type mapping for a region of memory
  * @start: start (physical address) of the region
  * @end: end (physical address) of the region
  * @type: A pointer to memtype, with requested type. On success, requested
@@ -732,7 +761,7 @@ EXPORT_SYMBOL_GPL(pat_pfn_immune_to_uc_mtrr);
  * On success, returns 0
  * On failure, returns non-zero
  */
-int io_reserve_memtype(resource_size_t start, resource_size_t end,
+int memtype_reserve_io(resource_size_t start, resource_size_t end,
 			enum page_cache_mode *type)
 {
 	resource_size_t size = end - start;
@@ -742,47 +771,47 @@ int io_reserve_memtype(resource_size_t start, resource_size_t end,
 
 	WARN_ON_ONCE(iomem_map_sanity_check(start, size));
 
-	ret = reserve_memtype(start, end, req_type, &new_type);
+	ret = memtype_reserve(start, end, req_type, &new_type);
 	if (ret)
 		goto out_err;
 
 	if (!is_new_memtype_allowed(start, size, req_type, new_type))
 		goto out_free;
 
-	if (kernel_map_sync_memtype(start, size, new_type) < 0)
+	if (memtype_kernel_map_sync(start, size, new_type) < 0)
 		goto out_free;
 
 	*type = new_type;
 	return 0;
 
 out_free:
-	free_memtype(start, end);
+	memtype_free(start, end);
 	ret = -EBUSY;
 out_err:
 	return ret;
 }
 
 /**
- * io_free_memtype - Release a memory type mapping for a region of memory
+ * memtype_free_io - Release a memory type mapping for a region of memory
  * @start: start (physical address) of the region
  * @end: end (physical address) of the region
  */
-void io_free_memtype(resource_size_t start, resource_size_t end)
+void memtype_free_io(resource_size_t start, resource_size_t end)
 {
-	free_memtype(start, end);
+	memtype_free(start, end);
 }
 
 int arch_io_reserve_memtype_wc(resource_size_t start, resource_size_t size)
 {
 	enum page_cache_mode type = _PAGE_CACHE_MODE_WC;
 
-	return io_reserve_memtype(start, start + size, &type);
+	return memtype_reserve_io(start, start + size, &type);
 }
 EXPORT_SYMBOL(arch_io_reserve_memtype_wc);
 
 void arch_io_free_memtype_wc(resource_size_t start, resource_size_t size)
 {
-	io_free_memtype(start, start + size);
+	memtype_free_io(start, start + size);
 }
 EXPORT_SYMBOL(arch_io_free_memtype_wc);
 
@@ -839,10 +868,10 @@ int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn,
 }
 
 /*
- * Change the memory type for the physial address range in kernel identity
+ * Change the memory type for the physical address range in kernel identity
  * mapping space if that range is a part of identity map.
  */
-int kernel_map_sync_memtype(u64 base, unsigned long size,
+int memtype_kernel_map_sync(u64 base, unsigned long size,
 			    enum page_cache_mode pcm)
 {
 	unsigned long id_sz;
@@ -851,15 +880,14 @@ int kernel_map_sync_memtype(u64 base, unsigned long size,
 		return 0;
 
 	/*
-	 * some areas in the middle of the kernel identity range
-	 * are not mapped, like the PCI space.
+	 * Some areas in the middle of the kernel identity range
+	 * are not mapped, for example the PCI space.
 	 */
 	if (!page_is_ram(base >> PAGE_SHIFT))
 		return 0;
 
 	id_sz = (__pa(high_memory-1) <= base + size) ?
-				__pa(high_memory) - base :
-				size;
+				__pa(high_memory) - base : size;
 
 	if (ioremap_change_attr((unsigned long)__va(base), id_sz, pcm) < 0) {
 		pr_info("x86/PAT: %s:%d ioremap_change_attr failed %s for [mem %#010Lx-%#010Lx]\n",
@@ -873,7 +901,7 @@ int kernel_map_sync_memtype(u64 base, unsigned long size,
 
 /*
  * Internal interface to reserve a range of physical memory with prot.
- * Reserved non RAM regions only and after successful reserve_memtype,
+ * Reserved non RAM regions only and after successful memtype_reserve,
  * this func also keeps identity mapping (if any) in sync with this new prot.
  */
 static int reserve_pfn_range(u64 paddr, unsigned long size, pgprot_t *vma_prot,
@@ -910,14 +938,14 @@ static int reserve_pfn_range(u64 paddr, unsigned long size, pgprot_t *vma_prot,
 		return 0;
 	}
 
-	ret = reserve_memtype(paddr, paddr + size, want_pcm, &pcm);
+	ret = memtype_reserve(paddr, paddr + size, want_pcm, &pcm);
 	if (ret)
 		return ret;
 
 	if (pcm != want_pcm) {
 		if (strict_prot ||
 		    !is_new_memtype_allowed(paddr, size, want_pcm, pcm)) {
-			free_memtype(paddr, paddr + size);
+			memtype_free(paddr, paddr + size);
 			pr_err("x86/PAT: %s:%d map pfn expected mapping type %s for [mem %#010Lx-%#010Lx], got %s\n",
 			       current->comm, current->pid,
 			       cattr_name(want_pcm),
@@ -935,8 +963,8 @@ static int reserve_pfn_range(u64 paddr, unsigned long size, pgprot_t *vma_prot,
 				     cachemode2protval(pcm));
 	}
 
-	if (kernel_map_sync_memtype(paddr, size, pcm) < 0) {
-		free_memtype(paddr, paddr + size);
+	if (memtype_kernel_map_sync(paddr, size, pcm) < 0) {
+		memtype_free(paddr, paddr + size);
 		return -EINVAL;
 	}
 	return 0;
@@ -952,7 +980,7 @@ static void free_pfn_range(u64 paddr, unsigned long size)
 
 	is_ram = pat_pagerange_is_ram(paddr, paddr + size);
 	if (is_ram == 0)
-		free_memtype(paddr, paddr + size);
+		memtype_free(paddr, paddr + size);
 }
 
 /*
@@ -1099,25 +1127,30 @@ EXPORT_SYMBOL_GPL(pgprot_writethrough);
 
 #if defined(CONFIG_DEBUG_FS) && defined(CONFIG_X86_PAT)
 
+/*
+ * We are allocating a temporary printout-entry to be passed
+ * between seq_start()/next() and seq_show():
+ */
 static struct memtype *memtype_get_idx(loff_t pos)
 {
-	struct memtype *print_entry;
+	struct memtype *entry_print;
 	int ret;
 
-	print_entry  = kzalloc(sizeof(struct memtype), GFP_KERNEL);
-	if (!print_entry)
+	entry_print  = kzalloc(sizeof(struct memtype), GFP_KERNEL);
+	if (!entry_print)
 		return NULL;
 
 	spin_lock(&memtype_lock);
-	ret = memtype_copy_nth_element(print_entry, pos);
+	ret = memtype_copy_nth_element(entry_print, pos);
 	spin_unlock(&memtype_lock);
 
-	if (!ret) {
-		return print_entry;
-	} else {
-		kfree(print_entry);
+	/* Free it on error: */
+	if (ret) {
+		kfree(entry_print);
 		return NULL;
 	}
+
+	return entry_print;
 }
 
 static void *memtype_seq_start(struct seq_file *seq, loff_t *pos)
@@ -1142,11 +1175,14 @@ static void memtype_seq_stop(struct seq_file *seq, void *v)
 
 static int memtype_seq_show(struct seq_file *seq, void *v)
 {
-	struct memtype *print_entry = (struct memtype *)v;
+	struct memtype *entry_print = (struct memtype *)v;
+
+	seq_printf(seq, "PAT: [mem 0x%016Lx-0x%016Lx] %s\n",
+			entry_print->start,
+			entry_print->end,
+			cattr_name(entry_print->type));
 
-	seq_printf(seq, "%s @ 0x%Lx-0x%Lx\n", cattr_name(print_entry->type),
-			print_entry->start, print_entry->end);
-	kfree(print_entry);
+	kfree(entry_print);
 
 	return 0;
 }
@@ -1178,7 +1214,6 @@ static int __init pat_memtype_list_init(void)
 	}
 	return 0;
 }
-
 late_initcall(pat_memtype_list_init);
 
 #endif /* CONFIG_DEBUG_FS && CONFIG_X86_PAT */
diff --git a/arch/x86/mm/pat_internal.h b/arch/x86/mm/pat/memtype.h
similarity index 81%
rename from arch/x86/mm/pat_internal.h
rename to arch/x86/mm/pat/memtype.h
index 79a06684349e21..cacecdbceb55ec 100644
--- a/arch/x86/mm/pat_internal.h
+++ b/arch/x86/mm/pat/memtype.h
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0 */
-#ifndef __PAT_INTERNAL_H_
-#define __PAT_INTERNAL_H_
+#ifndef __MEMTYPE_H_
+#define __MEMTYPE_H_
 
 extern int pat_debug_enable;
 
@@ -29,13 +29,13 @@ static inline char *cattr_name(enum page_cache_mode pcm)
 }
 
 #ifdef CONFIG_X86_PAT
-extern int memtype_check_insert(struct memtype *new,
+extern int memtype_check_insert(struct memtype *entry_new,
 				enum page_cache_mode *new_type);
 extern struct memtype *memtype_erase(u64 start, u64 end);
 extern struct memtype *memtype_lookup(u64 addr);
-extern int memtype_copy_nth_element(struct memtype *out, loff_t pos);
+extern int memtype_copy_nth_element(struct memtype *entry_out, loff_t pos);
 #else
-static inline int memtype_check_insert(struct memtype *new,
+static inline int memtype_check_insert(struct memtype *entry_new,
 				       enum page_cache_mode *new_type)
 { return 0; }
 static inline struct memtype *memtype_erase(u64 start, u64 end)
@@ -46,4 +46,4 @@ static inline int memtype_copy_nth_element(struct memtype *out, loff_t pos)
 { return 0; }
 #endif
 
-#endif /* __PAT_INTERNAL_H_ */
+#endif /* __MEMTYPE_H_ */
diff --git a/arch/x86/mm/pat/memtype_interval.c b/arch/x86/mm/pat/memtype_interval.c
new file mode 100644
index 00000000000000..a07e4882bf366d
--- /dev/null
+++ b/arch/x86/mm/pat/memtype_interval.c
@@ -0,0 +1,194 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Handle caching attributes in page tables (PAT)
+ *
+ * Authors: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
+ *          Suresh B Siddha <suresh.b.siddha@intel.com>
+ *
+ * Interval tree used to store the PAT memory type reservations.
+ */
+
+#include <linux/seq_file.h>
+#include <linux/debugfs.h>
+#include <linux/kernel.h>
+#include <linux/interval_tree_generic.h>
+#include <linux/sched.h>
+#include <linux/gfp.h>
+
+#include <asm/pgtable.h>
+#include <asm/memtype.h>
+
+#include "memtype.h"
+
+/*
+ * The memtype tree keeps track of memory type for specific
+ * physical memory areas. Without proper tracking, conflicting memory
+ * types in different mappings can cause CPU cache corruption.
+ *
+ * The tree is an interval tree (augmented rbtree) which tree is ordered
+ * by the starting address. The tree can contain multiple entries for
+ * different regions which overlap. All the aliases have the same
+ * cache attributes of course, as enforced by the PAT logic.
+ *
+ * memtype_lock protects the rbtree.
+ */
+
+static inline u64 interval_start(struct memtype *entry)
+{
+	return entry->start;
+}
+
+static inline u64 interval_end(struct memtype *entry)
+{
+	return entry->end - 1;
+}
+
+INTERVAL_TREE_DEFINE(struct memtype, rb, u64, subtree_max_end,
+		     interval_start, interval_end,
+		     static, interval)
+
+static struct rb_root_cached memtype_rbroot = RB_ROOT_CACHED;
+
+enum {
+	MEMTYPE_EXACT_MATCH	= 0,
+	MEMTYPE_END_MATCH	= 1
+};
+
+static struct memtype *memtype_match(u64 start, u64 end, int match_type)
+{
+	struct memtype *entry_match;
+
+	entry_match = interval_iter_first(&memtype_rbroot, start, end-1);
+
+	while (entry_match != NULL && entry_match->start < end) {
+		if ((match_type == MEMTYPE_EXACT_MATCH) &&
+		    (entry_match->start == start) && (entry_match->end == end))
+			return entry_match;
+
+		if ((match_type == MEMTYPE_END_MATCH) &&
+		    (entry_match->start < start) && (entry_match->end == end))
+			return entry_match;
+
+		entry_match = interval_iter_next(entry_match, start, end-1);
+	}
+
+	return NULL; /* Returns NULL if there is no match */
+}
+
+static int memtype_check_conflict(u64 start, u64 end,
+				  enum page_cache_mode reqtype,
+				  enum page_cache_mode *newtype)
+{
+	struct memtype *entry_match;
+	enum page_cache_mode found_type = reqtype;
+
+	entry_match = interval_iter_first(&memtype_rbroot, start, end-1);
+	if (entry_match == NULL)
+		goto success;
+
+	if (entry_match->type != found_type && newtype == NULL)
+		goto failure;
+
+	dprintk("Overlap at 0x%Lx-0x%Lx\n", entry_match->start, entry_match->end);
+	found_type = entry_match->type;
+
+	entry_match = interval_iter_next(entry_match, start, end-1);
+	while (entry_match) {
+		if (entry_match->type != found_type)
+			goto failure;
+
+		entry_match = interval_iter_next(entry_match, start, end-1);
+	}
+success:
+	if (newtype)
+		*newtype = found_type;
+
+	return 0;
+
+failure:
+	pr_info("x86/PAT: %s:%d conflicting memory types %Lx-%Lx %s<->%s\n",
+		current->comm, current->pid, start, end,
+		cattr_name(found_type), cattr_name(entry_match->type));
+
+	return -EBUSY;
+}
+
+int memtype_check_insert(struct memtype *entry_new, enum page_cache_mode *ret_type)
+{
+	int err = 0;
+
+	err = memtype_check_conflict(entry_new->start, entry_new->end, entry_new->type, ret_type);
+	if (err)
+		return err;
+
+	if (ret_type)
+		entry_new->type = *ret_type;
+
+	interval_insert(entry_new, &memtype_rbroot);
+	return 0;
+}
+
+struct memtype *memtype_erase(u64 start, u64 end)
+{
+	struct memtype *entry_old;
+
+	/*
+	 * Since the memtype_rbroot tree allows overlapping ranges,
+	 * memtype_erase() checks with EXACT_MATCH first, i.e. free
+	 * a whole node for the munmap case.  If no such entry is found,
+	 * it then checks with END_MATCH, i.e. shrink the size of a node
+	 * from the end for the mremap case.
+	 */
+	entry_old = memtype_match(start, end, MEMTYPE_EXACT_MATCH);
+	if (!entry_old) {
+		entry_old = memtype_match(start, end, MEMTYPE_END_MATCH);
+		if (!entry_old)
+			return ERR_PTR(-EINVAL);
+	}
+
+	if (entry_old->start == start) {
+		/* munmap: erase this node */
+		interval_remove(entry_old, &memtype_rbroot);
+	} else {
+		/* mremap: update the end value of this node */
+		interval_remove(entry_old, &memtype_rbroot);
+		entry_old->end = start;
+		interval_insert(entry_old, &memtype_rbroot);
+
+		return NULL;
+	}
+
+	return entry_old;
+}
+
+struct memtype *memtype_lookup(u64 addr)
+{
+	return interval_iter_first(&memtype_rbroot, addr, addr + PAGE_SIZE-1);
+}
+
+/*
+ * Debugging helper, copy the Nth entry of the tree into a
+ * a copy for printout. This allows us to print out the tree
+ * via debugfs, without holding the memtype_lock too long:
+ */
+#ifdef CONFIG_DEBUG_FS
+int memtype_copy_nth_element(struct memtype *entry_out, loff_t pos)
+{
+	struct memtype *entry_match;
+	int i = 1;
+
+	entry_match = interval_iter_first(&memtype_rbroot, 0, ULONG_MAX);
+
+	while (entry_match && pos != i) {
+		entry_match = interval_iter_next(entry_match, 0, ULONG_MAX);
+		i++;
+	}
+
+	if (entry_match) { /* pos == i */
+		*entry_out = *entry_match;
+		return 0;
+	} else {
+		return 1;
+	}
+}
+#endif
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pat/set_memory.c
similarity index 99%
rename from arch/x86/mm/pageattr.c
rename to arch/x86/mm/pat/set_memory.c
index 1b99ad05b11778..20823392f4f256 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pat/set_memory.c
@@ -24,10 +24,10 @@
 #include <linux/uaccess.h>
 #include <asm/pgalloc.h>
 #include <asm/proto.h>
-#include <asm/pat.h>
+#include <asm/memtype.h>
 #include <asm/set_memory.h>
 
-#include "mm_internal.h"
+#include "../mm_internal.h"
 
 /*
  * The current flushing context - we pass it instead of 5 arguments:
@@ -331,7 +331,7 @@ static void cpa_flush_all(unsigned long cache)
 	on_each_cpu(__cpa_flush_all, (void *) cache, 1);
 }
 
-void __cpa_flush_tlb(void *data)
+static void __cpa_flush_tlb(void *data)
 {
 	struct cpa_data *cpa = data;
 	unsigned int i;
@@ -1801,7 +1801,7 @@ int set_memory_uc(unsigned long addr, int numpages)
 	/*
 	 * for now UC MINUS. see comments in ioremap()
 	 */
-	ret = reserve_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE,
+	ret = memtype_reserve(__pa(addr), __pa(addr) + numpages * PAGE_SIZE,
 			      _PAGE_CACHE_MODE_UC_MINUS, NULL);
 	if (ret)
 		goto out_err;
@@ -1813,7 +1813,7 @@ int set_memory_uc(unsigned long addr, int numpages)
 	return 0;
 
 out_free:
-	free_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE);
+	memtype_free(__pa(addr), __pa(addr) + numpages * PAGE_SIZE);
 out_err:
 	return ret;
 }
@@ -1839,14 +1839,14 @@ int set_memory_wc(unsigned long addr, int numpages)
 {
 	int ret;
 
-	ret = reserve_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE,
+	ret = memtype_reserve(__pa(addr), __pa(addr) + numpages * PAGE_SIZE,
 		_PAGE_CACHE_MODE_WC, NULL);
 	if (ret)
 		return ret;
 
 	ret = _set_memory_wc(addr, numpages);
 	if (ret)
-		free_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE);
+		memtype_free(__pa(addr), __pa(addr) + numpages * PAGE_SIZE);
 
 	return ret;
 }
@@ -1873,7 +1873,7 @@ int set_memory_wb(unsigned long addr, int numpages)
 	if (ret)
 		return ret;
 
-	free_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE);
+	memtype_free(__pa(addr), __pa(addr) + numpages * PAGE_SIZE);
 	return 0;
 }
 EXPORT_SYMBOL(set_memory_wb);
@@ -2014,7 +2014,7 @@ static int _set_pages_array(struct page **pages, int numpages,
 			continue;
 		start = page_to_pfn(pages[i]) << PAGE_SHIFT;
 		end = start + PAGE_SIZE;
-		if (reserve_memtype(start, end, new_type, NULL))
+		if (memtype_reserve(start, end, new_type, NULL))
 			goto err_out;
 	}
 
@@ -2040,7 +2040,7 @@ static int _set_pages_array(struct page **pages, int numpages,
 			continue;
 		start = page_to_pfn(pages[i]) << PAGE_SHIFT;
 		end = start + PAGE_SIZE;
-		free_memtype(start, end);
+		memtype_free(start, end);
 	}
 	return -EINVAL;
 }
@@ -2089,7 +2089,7 @@ int set_pages_array_wb(struct page **pages, int numpages)
 			continue;
 		start = page_to_pfn(pages[i]) << PAGE_SHIFT;
 		end = start + PAGE_SIZE;
-		free_memtype(start, end);
+		memtype_free(start, end);
 	}
 
 	return 0;
@@ -2281,5 +2281,5 @@ int __init kernel_unmap_pages_in_pgd(pgd_t *pgd, unsigned long address,
  * be exposed to the rest of the kernel. Include these directly here.
  */
 #ifdef CONFIG_CPA_DEBUG
-#include "pageattr-test.c"
+#include "cpa-test.c"
 #endif
diff --git a/arch/x86/mm/pat_interval.c b/arch/x86/mm/pat_interval.c
deleted file mode 100644
index 6855362eaf21a6..00000000000000
--- a/arch/x86/mm/pat_interval.c
+++ /dev/null
@@ -1,185 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Handle caching attributes in page tables (PAT)
- *
- * Authors: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
- *          Suresh B Siddha <suresh.b.siddha@intel.com>
- *
- * Interval tree used to store the PAT memory type reservations.
- */
-
-#include <linux/seq_file.h>
-#include <linux/debugfs.h>
-#include <linux/kernel.h>
-#include <linux/interval_tree_generic.h>
-#include <linux/sched.h>
-#include <linux/gfp.h>
-
-#include <asm/pgtable.h>
-#include <asm/pat.h>
-
-#include "pat_internal.h"
-
-/*
- * The memtype tree keeps track of memory type for specific
- * physical memory areas. Without proper tracking, conflicting memory
- * types in different mappings can cause CPU cache corruption.
- *
- * The tree is an interval tree (augmented rbtree) with tree ordered
- * on starting address. Tree can contain multiple entries for
- * different regions which overlap. All the aliases have the same
- * cache attributes of course.
- *
- * memtype_lock protects the rbtree.
- */
-static inline u64 memtype_interval_start(struct memtype *memtype)
-{
-	return memtype->start;
-}
-
-static inline u64 memtype_interval_end(struct memtype *memtype)
-{
-	return memtype->end - 1;
-}
-INTERVAL_TREE_DEFINE(struct memtype, rb, u64, subtree_max_end,
-		     memtype_interval_start, memtype_interval_end,
-		     static, memtype_interval)
-
-static struct rb_root_cached memtype_rbroot = RB_ROOT_CACHED;
-
-enum {
-	MEMTYPE_EXACT_MATCH	= 0,
-	MEMTYPE_END_MATCH	= 1
-};
-
-static struct memtype *memtype_match(u64 start, u64 end, int match_type)
-{
-	struct memtype *match;
-
-	match = memtype_interval_iter_first(&memtype_rbroot, start, end-1);
-	while (match != NULL && match->start < end) {
-		if ((match_type == MEMTYPE_EXACT_MATCH) &&
-		    (match->start == start) && (match->end == end))
-			return match;
-
-		if ((match_type == MEMTYPE_END_MATCH) &&
-		    (match->start < start) && (match->end == end))
-			return match;
-
-		match = memtype_interval_iter_next(match, start, end-1);
-	}
-
-	return NULL; /* Returns NULL if there is no match */
-}
-
-static int memtype_check_conflict(u64 start, u64 end,
-				  enum page_cache_mode reqtype,
-				  enum page_cache_mode *newtype)
-{
-	struct memtype *match;
-	enum page_cache_mode found_type = reqtype;
-
-	match = memtype_interval_iter_first(&memtype_rbroot, start, end-1);
-	if (match == NULL)
-		goto success;
-
-	if (match->type != found_type && newtype == NULL)
-		goto failure;
-
-	dprintk("Overlap at 0x%Lx-0x%Lx\n", match->start, match->end);
-	found_type = match->type;
-
-	match = memtype_interval_iter_next(match, start, end-1);
-	while (match) {
-		if (match->type != found_type)
-			goto failure;
-
-		match = memtype_interval_iter_next(match, start, end-1);
-	}
-success:
-	if (newtype)
-		*newtype = found_type;
-
-	return 0;
-
-failure:
-	pr_info("x86/PAT: %s:%d conflicting memory types %Lx-%Lx %s<->%s\n",
-		current->comm, current->pid, start, end,
-		cattr_name(found_type), cattr_name(match->type));
-	return -EBUSY;
-}
-
-int memtype_check_insert(struct memtype *new,
-			 enum page_cache_mode *ret_type)
-{
-	int err = 0;
-
-	err = memtype_check_conflict(new->start, new->end, new->type, ret_type);
-	if (err)
-		return err;
-
-	if (ret_type)
-		new->type = *ret_type;
-
-	memtype_interval_insert(new, &memtype_rbroot);
-	return 0;
-}
-
-struct memtype *memtype_erase(u64 start, u64 end)
-{
-	struct memtype *data;
-
-	/*
-	 * Since the memtype_rbroot tree allows overlapping ranges,
-	 * memtype_erase() checks with EXACT_MATCH first, i.e. free
-	 * a whole node for the munmap case.  If no such entry is found,
-	 * it then checks with END_MATCH, i.e. shrink the size of a node
-	 * from the end for the mremap case.
-	 */
-	data = memtype_match(start, end, MEMTYPE_EXACT_MATCH);
-	if (!data) {
-		data = memtype_match(start, end, MEMTYPE_END_MATCH);
-		if (!data)
-			return ERR_PTR(-EINVAL);
-	}
-
-	if (data->start == start) {
-		/* munmap: erase this node */
-		memtype_interval_remove(data, &memtype_rbroot);
-	} else {
-		/* mremap: update the end value of this node */
-		memtype_interval_remove(data, &memtype_rbroot);
-		data->end = start;
-		memtype_interval_insert(data, &memtype_rbroot);
-		return NULL;
-	}
-
-	return data;
-}
-
-struct memtype *memtype_lookup(u64 addr)
-{
-	return memtype_interval_iter_first(&memtype_rbroot, addr,
-					   addr + PAGE_SIZE-1);
-}
-
-#if defined(CONFIG_DEBUG_FS)
-int memtype_copy_nth_element(struct memtype *out, loff_t pos)
-{
-	struct memtype *match;
-	int i = 1;
-
-	match = memtype_interval_iter_first(&memtype_rbroot, 0, ULONG_MAX);
-	while (match && pos != i) {
-		match = memtype_interval_iter_next(match, 0, ULONG_MAX);
-		i++;
-	}
-
-	if (match) { /* pos == i */
-		*out = *match;
-		return 0;
-	} else {
-		return 1;
-	}
-}
-#endif
diff --git a/arch/x86/mm/pgtable_32.c b/arch/x86/mm/pgtable_32.c
index 9bb7f0ab9fe625..0e6700eaa4f921 100644
--- a/arch/x86/mm/pgtable_32.c
+++ b/arch/x86/mm/pgtable_32.c
@@ -18,6 +18,7 @@
 #include <asm/tlb.h>
 #include <asm/tlbflush.h>
 #include <asm/io.h>
+#include <linux/vmalloc.h>
 
 unsigned int __VMALLOC_RESERVE = 128 << 20;
 
diff --git a/arch/x86/mm/physaddr.c b/arch/x86/mm/physaddr.c
index bdc98150d4db88..fc3f3d3e2ef210 100644
--- a/arch/x86/mm/physaddr.c
+++ b/arch/x86/mm/physaddr.c
@@ -5,6 +5,7 @@
 #include <linux/mm.h>
 
 #include <asm/page.h>
+#include <linux/vmalloc.h>
 
 #include "physaddr.h"
 
diff --git a/arch/x86/pci/i386.c b/arch/x86/pci/i386.c
index 9df652d3d9275b..fa855bbaebaf19 100644
--- a/arch/x86/pci/i386.c
+++ b/arch/x86/pci/i386.c
@@ -34,7 +34,7 @@
 #include <linux/errno.h>
 #include <linux/memblock.h>
 
-#include <asm/pat.h>
+#include <asm/memtype.h>
 #include <asm/e820/api.h>
 #include <asm/pci_x86.h>
 #include <asm/io_apic.h>
diff --git a/arch/x86/xen/mmu_pv.c b/arch/x86/xen/mmu_pv.c
index c8dbee62ec2ab1..bbba8b17829a18 100644
--- a/arch/x86/xen/mmu_pv.c
+++ b/arch/x86/xen/mmu_pv.c
@@ -67,7 +67,7 @@
 #include <asm/linkage.h>
 #include <asm/page.h>
 #include <asm/init.h>
-#include <asm/pat.h>
+#include <asm/memtype.h>
 #include <asm/smp.h>
 #include <asm/tlb.h>
 
diff --git a/arch/xtensa/include/asm/vmalloc.h b/arch/xtensa/include/asm/vmalloc.h
new file mode 100644
index 00000000000000..0eb94b70be55df
--- /dev/null
+++ b/arch/xtensa/include/asm/vmalloc.h
@@ -0,0 +1,4 @@
+#ifndef _ASM_XTENSA_VMALLOC_H
+#define _ASM_XTENSA_VMALLOC_H
+
+#endif /* _ASM_XTENSA_VMALLOC_H */
diff --git a/drivers/infiniband/hw/mlx5/main.c b/drivers/infiniband/hw/mlx5/main.c
index 997cbfe4b90ce4..df88bfbd7fed32 100644
--- a/drivers/infiniband/hw/mlx5/main.c
+++ b/drivers/infiniband/hw/mlx5/main.c
@@ -40,7 +40,7 @@
 #include <linux/slab.h>
 #include <linux/bitmap.h>
 #if defined(CONFIG_X86)
-#include <asm/pat.h>
+#include <asm/memtype.h>
 #endif
 #include <linux/sched.h>
 #include <linux/sched/mm.h>
diff --git a/drivers/media/pci/ivtv/ivtvfb.c b/drivers/media/pci/ivtv/ivtvfb.c
index 95a56cce9b657c..1daf9e07cad748 100644
--- a/drivers/media/pci/ivtv/ivtvfb.c
+++ b/drivers/media/pci/ivtv/ivtvfb.c
@@ -37,7 +37,7 @@
 #include <linux/ivtvfb.h>
 
 #ifdef CONFIG_X86_64
-#include <asm/pat.h>
+#include <asm/memtype.h>
 #endif
 
 /* card parameters */
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 80a9162b406c26..5dfbc0e56e679f 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -625,24 +625,19 @@ unsigned long vmalloc_to_pfn(const void *addr);
  * On nommu, vmalloc/vfree wrap through kmalloc/kfree directly, so there
  * is no special casing required.
  */
-static inline bool is_vmalloc_addr(const void *x)
-{
-#ifdef CONFIG_MMU
-	unsigned long addr = (unsigned long)x;
-
-	return addr >= VMALLOC_START && addr < VMALLOC_END;
-#else
-	return false;
-#endif
-}
 
 #ifndef is_ioremap_addr
 #define is_ioremap_addr(x) is_vmalloc_addr(x)
 #endif
 
 #ifdef CONFIG_MMU
+extern bool is_vmalloc_addr(const void *x);
 extern int is_vmalloc_or_module_addr(const void *x);
 #else
+static inline bool is_vmalloc_addr(const void *x)
+{
+	return false;
+}
 static inline int is_vmalloc_or_module_addr(const void *x)
 {
 	return 0;
diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
index a4b24110277199..ec38132366992e 100644
--- a/include/linux/vmalloc.h
+++ b/include/linux/vmalloc.h
@@ -10,6 +10,8 @@
 #include <linux/rbtree.h>
 #include <linux/overflow.h>
 
+#include <asm/vmalloc.h>
+
 struct vm_area_struct;		/* vma defining user mapping in mm_types.h */
 struct notifier_block;		/* in notifier.h */
 
diff --git a/mm/highmem.c b/mm/highmem.c
index 107b10f9878ef7..64d8dea47dd1a8 100644
--- a/mm/highmem.c
+++ b/mm/highmem.c
@@ -29,7 +29,7 @@
 #include <linux/highmem.h>
 #include <linux/kgdb.h>
 #include <asm/tlbflush.h>
-
+#include <linux/vmalloc.h>
 
 #if defined(CONFIG_HIGHMEM) || defined(CONFIG_X86_32)
 DEFINE_PER_CPU(int, __kmap_atomic_idx);
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index e9681dc4aa754e..8e83025686996a 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -41,6 +41,14 @@
 
 #include "internal.h"
 
+bool is_vmalloc_addr(const void *x)
+{
+	unsigned long addr = (unsigned long)x;
+
+	return addr >= VMALLOC_START && addr < VMALLOC_END;
+}
+EXPORT_SYMBOL(is_vmalloc_addr);
+
 struct vfree_deferred {
 	struct llist_head list;
 	struct work_struct wq;