Linux-libre 4.5-gnu

15 files changed, 385 insertions, 69 deletions

diff --git a/arch/arm64/mm/cache.S b/arch/arm64/mm/cache.S
index cfa44a6ad..6df07069a 100644
--- a/arch/arm64/mm/cache.S
+++ b/arch/arm64/mm/cache.S
@@ -81,26 +81,32 @@ ENDPROC(__flush_cache_user_range)
 /*
  *	__flush_dcache_area(kaddr, size)
  *
- *	Ensure that the data held in the page kaddr is written back to the
- *	page in question.
+ *	Ensure that any D-cache lines for the interval [kaddr, kaddr+size)
+ *	are cleaned and invalidated to the PoC.
  *
  *	- kaddr   - kernel address
  *	- size    - size in question
  */
 ENTRY(__flush_dcache_area)
-	dcache_line_size x2, x3
-	add	x1, x0, x1
-	sub	x3, x2, #1
-	bic	x0, x0, x3
-1:	dc	civac, x0			// clean & invalidate D line / unified line
-	add	x0, x0, x2
-	cmp	x0, x1
-	b.lo	1b
-	dsb	sy
+	dcache_by_line_op civac, sy, x0, x1, x2, x3
 	ret
 ENDPIPROC(__flush_dcache_area)
 
 /*
+ *	__clean_dcache_area_pou(kaddr, size)
+ *
+ * 	Ensure that any D-cache lines for the interval [kaddr, kaddr+size)
+ * 	are cleaned to the PoU.
+ *
+ *	- kaddr   - kernel address
+ *	- size    - size in question
+ */
+ENTRY(__clean_dcache_area_pou)
+	dcache_by_line_op cvau, ish, x0, x1, x2, x3
+	ret
+ENDPROC(__clean_dcache_area_pou)
+
+/*
  *	__inval_cache_range(start, end)
  *	- start   - start address of region
  *	- end     - end address of region
diff --git a/arch/arm64/mm/copypage.c b/arch/arm64/mm/copypage.c
index 13bbc3be6..22e4cb4d6 100644
--- a/arch/arm64/mm/copypage.c
+++ b/arch/arm64/mm/copypage.c
@@ -24,8 +24,9 @@
 
 void __cpu_copy_user_page(void *kto, const void *kfrom, unsigned long vaddr)
 {
+	struct page *page = virt_to_page(kto);
 	copy_page(kto, kfrom);
-	__flush_dcache_area(kto, PAGE_SIZE);
+	flush_dcache_page(page);
 }
 EXPORT_SYMBOL_GPL(__cpu_copy_user_page);
 
diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
index 354144e33..a6e757cba 100644
--- a/arch/arm64/mm/dma-mapping.c
+++ b/arch/arm64/mm/dma-mapping.c
@@ -40,7 +40,7 @@ static pgprot_t __get_dma_pgprot(struct dma_attrs *attrs, pgprot_t prot,
 static struct gen_pool *atomic_pool;
 
 #define DEFAULT_DMA_COHERENT_POOL_SIZE  SZ_256K
-static size_t atomic_pool_size = DEFAULT_DMA_COHERENT_POOL_SIZE;
+static size_t atomic_pool_size __initdata = DEFAULT_DMA_COHERENT_POOL_SIZE;
 
 static int __init early_coherent_pool(char *p)
 {
@@ -896,7 +896,7 @@ static int __iommu_attach_notifier(struct notifier_block *nb,
 	return 0;
 }
 
-static int register_iommu_dma_ops_notifier(struct bus_type *bus)
+static int __init register_iommu_dma_ops_notifier(struct bus_type *bus)
 {
 	struct notifier_block *nb = kzalloc(sizeof(*nb), GFP_KERNEL);
 	int ret;
diff --git a/arch/arm64/mm/dump.c b/arch/arm64/mm/dump.c
index 5a22a119a..0adbebbc2 100644
--- a/arch/arm64/mm/dump.c
+++ b/arch/arm64/mm/dump.c
@@ -46,7 +46,7 @@ enum address_markers_idx {
 	PCI_START_NR,
 	PCI_END_NR,
 	MODULES_START_NR,
-	MODUELS_END_NR,
+	MODULES_END_NR,
 	KERNEL_SPACE_NR,
 };
 
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 92ddac1e8..abe2a9542 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -371,6 +371,13 @@ static int __kprobes do_translation_fault(unsigned long addr,
 	return 0;
 }
 
+static int do_alignment_fault(unsigned long addr, unsigned int esr,
+			      struct pt_regs *regs)
+{
+	do_bad_area(addr, esr, regs);
+	return 0;
+}
+
 /*
  * This abort handler always returns "fault".
  */
@@ -418,7 +425,7 @@ static struct fault_info {
 	{ do_bad,		SIGBUS,  0,		"synchronous parity error (translation table walk)" },
 	{ do_bad,		SIGBUS,  0,		"synchronous parity error (translation table walk)" },
 	{ do_bad,		SIGBUS,  0,		"unknown 32"			},
-	{ do_bad,		SIGBUS,  BUS_ADRALN,	"alignment fault"		},
+	{ do_alignment_fault,	SIGBUS,  BUS_ADRALN,	"alignment fault"		},
 	{ do_bad,		SIGBUS,  0,		"unknown 34"			},
 	{ do_bad,		SIGBUS,  0,		"unknown 35"			},
 	{ do_bad,		SIGBUS,  0,		"unknown 36"			},
diff --git a/arch/arm64/mm/flush.c b/arch/arm64/mm/flush.c
index c26b80401..60585bde1 100644
--- a/arch/arm64/mm/flush.c
+++ b/arch/arm64/mm/flush.c
@@ -34,19 +34,24 @@ void flush_cache_range(struct vm_area_struct *vma, unsigned long start,
 		__flush_icache_all();
 }
 
+static void sync_icache_aliases(void *kaddr, unsigned long len)
+{
+	unsigned long addr = (unsigned long)kaddr;
+
+	if (icache_is_aliasing()) {
+		__clean_dcache_area_pou(kaddr, len);
+		__flush_icache_all();
+	} else {
+		flush_icache_range(addr, addr + len);
+	}
+}
+
 static void flush_ptrace_access(struct vm_area_struct *vma, struct page *page,
 				unsigned long uaddr, void *kaddr,
 				unsigned long len)
 {
-	if (vma->vm_flags & VM_EXEC) {
-		unsigned long addr = (unsigned long)kaddr;
-		if (icache_is_aliasing()) {
-			__flush_dcache_area(kaddr, len);
-			__flush_icache_all();
-		} else {
-			flush_icache_range(addr, addr + len);
-		}
-	}
+	if (vma->vm_flags & VM_EXEC)
+		sync_icache_aliases(kaddr, len);
 }
 
 /*
@@ -74,13 +79,11 @@ void __sync_icache_dcache(pte_t pte, unsigned long addr)
 	if (!page_mapping(page))
 		return;
 
-	if (!test_and_set_bit(PG_dcache_clean, &page->flags)) {
-		__flush_dcache_area(page_address(page),
-				PAGE_SIZE << compound_order(page));
+	if (!test_and_set_bit(PG_dcache_clean, &page->flags))
+		sync_icache_aliases(page_address(page),
+				    PAGE_SIZE << compound_order(page));
+	else if (icache_is_aivivt())
 		__flush_icache_all();
-	} else if (icache_is_aivivt()) {
-		__flush_icache_all();
-	}
 }
 
 /*
@@ -99,19 +102,3 @@ EXPORT_SYMBOL(flush_dcache_page);
  * Additional functions defined in assembly.
  */
 EXPORT_SYMBOL(flush_icache_range);
-
-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
-#ifdef CONFIG_HAVE_RCU_TABLE_FREE
-void pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address,
-			  pmd_t *pmdp)
-{
-	pmd_t pmd = pmd_mksplitting(*pmdp);
-
-	VM_BUG_ON(address & ~PMD_MASK);
-	set_pmd_at(vma->vm_mm, address, pmdp, pmd);
-
-	/* dummy IPI to serialise against fast_gup */
-	kick_all_cpus_sync();
-}
-#endif /* CONFIG_HAVE_RCU_TABLE_FREE */
-#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index 383b03ff3..da30529bb 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -41,15 +41,273 @@ int pud_huge(pud_t pud)
 #endif
 }
 
+static int find_num_contig(struct mm_struct *mm, unsigned long addr,
+			   pte_t *ptep, pte_t pte, size_t *pgsize)
+{
+	pgd_t *pgd = pgd_offset(mm, addr);
+	pud_t *pud;
+	pmd_t *pmd;
+
+	*pgsize = PAGE_SIZE;
+	if (!pte_cont(pte))
+		return 1;
+	if (!pgd_present(*pgd)) {
+		VM_BUG_ON(!pgd_present(*pgd));
+		return 1;
+	}
+	pud = pud_offset(pgd, addr);
+	if (!pud_present(*pud)) {
+		VM_BUG_ON(!pud_present(*pud));
+		return 1;
+	}
+	pmd = pmd_offset(pud, addr);
+	if (!pmd_present(*pmd)) {
+		VM_BUG_ON(!pmd_present(*pmd));
+		return 1;
+	}
+	if ((pte_t *)pmd == ptep) {
+		*pgsize = PMD_SIZE;
+		return CONT_PMDS;
+	}
+	return CONT_PTES;
+}
+
+void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
+			    pte_t *ptep, pte_t pte)
+{
+	size_t pgsize;
+	int i;
+	int ncontig = find_num_contig(mm, addr, ptep, pte, &pgsize);
+	unsigned long pfn;
+	pgprot_t hugeprot;
+
+	if (ncontig == 1) {
+		set_pte_at(mm, addr, ptep, pte);
+		return;
+	}
+
+	pfn = pte_pfn(pte);
+	hugeprot = __pgprot(pte_val(pfn_pte(pfn, __pgprot(0))) ^ pte_val(pte));
+	for (i = 0; i < ncontig; i++) {
+		pr_debug("%s: set pte %p to 0x%llx\n", __func__, ptep,
+			 pte_val(pfn_pte(pfn, hugeprot)));
+		set_pte_at(mm, addr, ptep, pfn_pte(pfn, hugeprot));
+		ptep++;
+		pfn += pgsize >> PAGE_SHIFT;
+		addr += pgsize;
+	}
+}
+
+pte_t *huge_pte_alloc(struct mm_struct *mm,
+		      unsigned long addr, unsigned long sz)
+{
+	pgd_t *pgd;
+	pud_t *pud;
+	pte_t *pte = NULL;
+
+	pr_debug("%s: addr:0x%lx sz:0x%lx\n", __func__, addr, sz);
+	pgd = pgd_offset(mm, addr);
+	pud = pud_alloc(mm, pgd, addr);
+	if (!pud)
+		return NULL;
+
+	if (sz == PUD_SIZE) {
+		pte = (pte_t *)pud;
+	} else if (sz == (PAGE_SIZE * CONT_PTES)) {
+		pmd_t *pmd = pmd_alloc(mm, pud, addr);
+
+		WARN_ON(addr & (sz - 1));
+		/*
+		 * Note that if this code were ever ported to the
+		 * 32-bit arm platform then it will cause trouble in
+		 * the case where CONFIG_HIGHPTE is set, since there
+		 * will be no pte_unmap() to correspond with this
+		 * pte_alloc_map().
+		 */
+		pte = pte_alloc_map(mm, NULL, pmd, addr);
+	} else if (sz == PMD_SIZE) {
+		if (IS_ENABLED(CONFIG_ARCH_WANT_HUGE_PMD_SHARE) &&
+		    pud_none(*pud))
+			pte = huge_pmd_share(mm, addr, pud);
+		else
+			pte = (pte_t *)pmd_alloc(mm, pud, addr);
+	} else if (sz == (PMD_SIZE * CONT_PMDS)) {
+		pmd_t *pmd;
+
+		pmd = pmd_alloc(mm, pud, addr);
+		WARN_ON(addr & (sz - 1));
+		return (pte_t *)pmd;
+	}
+
+	pr_debug("%s: addr:0x%lx sz:0x%lx ret pte=%p/0x%llx\n", __func__, addr,
+	       sz, pte, pte_val(*pte));
+	return pte;
+}
+
+pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
+{
+	pgd_t *pgd;
+	pud_t *pud;
+	pmd_t *pmd = NULL;
+	pte_t *pte = NULL;
+
+	pgd = pgd_offset(mm, addr);
+	pr_debug("%s: addr:0x%lx pgd:%p\n", __func__, addr, pgd);
+	if (!pgd_present(*pgd))
+		return NULL;
+	pud = pud_offset(pgd, addr);
+	if (!pud_present(*pud))
+		return NULL;
+
+	if (pud_huge(*pud))
+		return (pte_t *)pud;
+	pmd = pmd_offset(pud, addr);
+	if (!pmd_present(*pmd))
+		return NULL;
+
+	if (pte_cont(pmd_pte(*pmd))) {
+		pmd = pmd_offset(
+			pud, (addr & CONT_PMD_MASK));
+		return (pte_t *)pmd;
+	}
+	if (pmd_huge(*pmd))
+		return (pte_t *)pmd;
+	pte = pte_offset_kernel(pmd, addr);
+	if (pte_present(*pte) && pte_cont(*pte)) {
+		pte = pte_offset_kernel(
+			pmd, (addr & CONT_PTE_MASK));
+		return pte;
+	}
+	return NULL;
+}
+
+pte_t arch_make_huge_pte(pte_t entry, struct vm_area_struct *vma,
+			 struct page *page, int writable)
+{
+	size_t pagesize = huge_page_size(hstate_vma(vma));
+
+	if (pagesize == CONT_PTE_SIZE) {
+		entry = pte_mkcont(entry);
+	} else if (pagesize == CONT_PMD_SIZE) {
+		entry = pmd_pte(pmd_mkcont(pte_pmd(entry)));
+	} else if (pagesize != PUD_SIZE && pagesize != PMD_SIZE) {
+		pr_warn("%s: unrecognized huge page size 0x%lx\n",
+			__func__, pagesize);
+	}
+	return entry;
+}
+
+pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
+			      unsigned long addr, pte_t *ptep)
+{
+	pte_t pte;
+
+	if (pte_cont(*ptep)) {
+		int ncontig, i;
+		size_t pgsize;
+		pte_t *cpte;
+		bool is_dirty = false;
+
+		cpte = huge_pte_offset(mm, addr);
+		ncontig = find_num_contig(mm, addr, cpte, *cpte, &pgsize);
+		/* save the 1st pte to return */
+		pte = ptep_get_and_clear(mm, addr, cpte);
+		for (i = 1; i < ncontig; ++i) {
+			/*
+			 * If HW_AFDBM is enabled, then the HW could
+			 * turn on the dirty bit for any of the page
+			 * in the set, so check them all.
+			 */
+			++cpte;
+			if (pte_dirty(ptep_get_and_clear(mm, addr, cpte)))
+				is_dirty = true;
+		}
+		if (is_dirty)
+			return pte_mkdirty(pte);
+		else
+			return pte;
+	} else {
+		return ptep_get_and_clear(mm, addr, ptep);
+	}
+}
+
+int huge_ptep_set_access_flags(struct vm_area_struct *vma,
+			       unsigned long addr, pte_t *ptep,
+			       pte_t pte, int dirty)
+{
+	pte_t *cpte;
+
+	if (pte_cont(pte)) {
+		int ncontig, i, changed = 0;
+		size_t pgsize = 0;
+		unsigned long pfn = pte_pfn(pte);
+		/* Select all bits except the pfn */
+		pgprot_t hugeprot =
+			__pgprot(pte_val(pfn_pte(pfn, __pgprot(0))) ^
+				 pte_val(pte));
+
+		cpte = huge_pte_offset(vma->vm_mm, addr);
+		pfn = pte_pfn(*cpte);
+		ncontig = find_num_contig(vma->vm_mm, addr, cpte,
+					  *cpte, &pgsize);
+		for (i = 0; i < ncontig; ++i, ++cpte) {
+			changed = ptep_set_access_flags(vma, addr, cpte,
+							pfn_pte(pfn,
+								hugeprot),
+							dirty);
+			pfn += pgsize >> PAGE_SHIFT;
+		}
+		return changed;
+	} else {
+		return ptep_set_access_flags(vma, addr, ptep, pte, dirty);
+	}
+}
+
+void huge_ptep_set_wrprotect(struct mm_struct *mm,
+			     unsigned long addr, pte_t *ptep)
+{
+	if (pte_cont(*ptep)) {
+		int ncontig, i;
+		pte_t *cpte;
+		size_t pgsize = 0;
+
+		cpte = huge_pte_offset(mm, addr);
+		ncontig = find_num_contig(mm, addr, cpte, *cpte, &pgsize);
+		for (i = 0; i < ncontig; ++i, ++cpte)
+			ptep_set_wrprotect(mm, addr, cpte);
+	} else {
+		ptep_set_wrprotect(mm, addr, ptep);
+	}
+}
+
+void huge_ptep_clear_flush(struct vm_area_struct *vma,
+			   unsigned long addr, pte_t *ptep)
+{
+	if (pte_cont(*ptep)) {
+		int ncontig, i;
+		pte_t *cpte;
+		size_t pgsize = 0;
+
+		cpte = huge_pte_offset(vma->vm_mm, addr);
+		ncontig = find_num_contig(vma->vm_mm, addr, cpte,
+					  *cpte, &pgsize);
+		for (i = 0; i < ncontig; ++i, ++cpte)
+			ptep_clear_flush(vma, addr, cpte);
+	} else {
+		ptep_clear_flush(vma, addr, ptep);
+	}
+}
+
 static __init int setup_hugepagesz(char *opt)
 {
 	unsigned long ps = memparse(opt, &opt);
+
 	if (ps == PMD_SIZE) {
 		hugetlb_add_hstate(PMD_SHIFT - PAGE_SHIFT);
 	} else if (ps == PUD_SIZE) {
 		hugetlb_add_hstate(PUD_SHIFT - PAGE_SHIFT);
 	} else {
-		pr_err("hugepagesz: Unsupported page size %lu M\n", ps >> 20);
+		pr_err("hugepagesz: Unsupported page size %lu K\n", ps >> 10);
 		return 0;
 	}
 	return 1;
diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index 4cb98aa8c..7802f216a 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -71,7 +71,7 @@ early_param("initrd", early_initrd);
  * currently assumes that for memory starting above 4G, 32-bit devices will
  * use a DMA offset.
  */
-static phys_addr_t max_zone_dma_phys(void)
+static phys_addr_t __init max_zone_dma_phys(void)
 {
 	phys_addr_t offset = memblock_start_of_DRAM() & GENMASK_ULL(63, 32);
 	return min(offset + (1ULL << 32), memblock_end_of_DRAM());
@@ -120,17 +120,17 @@ static void __init zone_sizes_init(unsigned long min, unsigned long max)
 #ifdef CONFIG_HAVE_ARCH_PFN_VALID
 int pfn_valid(unsigned long pfn)
 {
-	return memblock_is_memory(pfn << PAGE_SHIFT);
+	return memblock_is_map_memory(pfn << PAGE_SHIFT);
 }
 EXPORT_SYMBOL(pfn_valid);
 #endif
 
 #ifndef CONFIG_SPARSEMEM
-static void arm64_memory_present(void)
+static void __init arm64_memory_present(void)
 {
 }
 #else
-static void arm64_memory_present(void)
+static void __init arm64_memory_present(void)
 {
 	struct memblock_region *reg;
 
@@ -360,7 +360,6 @@ void free_initmem(void)
 {
 	fixup_init();
 	free_initmem_default(0);
-	free_alternatives_memory();
 }
 
 #ifdef CONFIG_BLK_DEV_INITRD
diff --git a/arch/arm64/mm/kasan_init.c b/arch/arm64/mm/kasan_init.c
index cf038c7d9..cab7a5be4 100644
--- a/arch/arm64/mm/kasan_init.c
+++ b/arch/arm64/mm/kasan_init.c
@@ -120,6 +120,7 @@ static void __init cpu_set_ttbr1(unsigned long ttbr1)
 void __init kasan_init(void)
 {
 	struct memblock_region *reg;
+	int i;
 
 	/*
 	 * We are going to perform proper setup of shadow memory.
@@ -155,6 +156,14 @@ void __init kasan_init(void)
 				pfn_to_nid(virt_to_pfn(start)));
 	}
 
+	/*
+	 * KAsan may reuse the contents of kasan_zero_pte directly, so we
+	 * should make sure that it maps the zero page read-only.
+	 */
+	for (i = 0; i < PTRS_PER_PTE; i++)
+		set_pte(&kasan_zero_pte[i],
+			pfn_pte(virt_to_pfn(kasan_zero_page), PAGE_KERNEL_RO));
+
 	memset(kasan_zero_page, 0, PAGE_SIZE);
 	cpu_set_ttbr1(__pa(swapper_pg_dir));
 	flush_tlb_all();
diff --git a/arch/arm64/mm/mmap.c b/arch/arm64/mm/mmap.c
index ed177475d..232f787a0 100644
--- a/arch/arm64/mm/mmap.c
+++ b/arch/arm64/mm/mmap.c
@@ -51,8 +51,12 @@ unsigned long arch_mmap_rnd(void)
 {
 	unsigned long rnd;
 
-	rnd = (unsigned long)get_random_int() & STACK_RND_MASK;
-
+#ifdef CONFIG_COMPAT
+	if (test_thread_flag(TIF_32BIT))
+		rnd = get_random_long() & ((1UL << mmap_rnd_compat_bits) - 1);
+	else
+#endif
+		rnd = get_random_long() & ((1UL << mmap_rnd_bits) - 1);
 	return rnd << PAGE_SHIFT;
 }
 
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index 116ad654d..58faeaa7f 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -251,6 +251,14 @@ static void  __create_mapping(struct mm_struct *mm, pgd_t *pgd,
 {
 	unsigned long addr, length, end, next;
 
+	/*
+	 * If the virtual and physical address don't have the same offset
+	 * within a page, we cannot map the region as the caller expects.
+	 */
+	if (WARN_ON((phys ^ virt) & ~PAGE_MASK))
+		return;
+
+	phys &= PAGE_MASK;
 	addr = virt & PAGE_MASK;
 	length = PAGE_ALIGN(size + (virt & ~PAGE_MASK));
 
@@ -280,7 +288,7 @@ static void __init create_mapping(phys_addr_t phys, unsigned long virt,
 			&phys, virt);
 		return;
 	}
-	__create_mapping(&init_mm, pgd_offset_k(virt & PAGE_MASK), phys, virt,
+	__create_mapping(&init_mm, pgd_offset_k(virt), phys, virt,
 			 size, prot, early_alloc);
 }
 
@@ -301,7 +309,7 @@ static void create_mapping_late(phys_addr_t phys, unsigned long virt,
 		return;
 	}
 
-	return __create_mapping(&init_mm, pgd_offset_k(virt & PAGE_MASK),
+	return __create_mapping(&init_mm, pgd_offset_k(virt),
 				phys, virt, size, prot, late_alloc);
 }
 
@@ -372,6 +380,8 @@ static void __init map_mem(void)
 
 		if (start >= end)
 			break;
+		if (memblock_is_nomap(reg))
+			continue;
 
 		if (ARM64_SWAPPER_USES_SECTION_MAPS) {
 			/*
diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c
index cf6240741..0795c3a36 100644
--- a/arch/arm64/mm/pageattr.c
+++ b/arch/arm64/mm/pageattr.c
@@ -14,6 +14,7 @@
 #include <linux/mm.h>
 #include <linux/module.h>
 #include <linux/sched.h>
+#include <linux/vmalloc.h>
 
 #include <asm/pgtable.h>
 #include <asm/tlbflush.h>
@@ -44,6 +45,7 @@ static int change_memory_common(unsigned long addr, int numpages,
 	unsigned long end = start + size;
 	int ret;
 	struct page_change_data data;
+	struct vm_struct *area;
 
 	if (!PAGE_ALIGNED(addr)) {
 		start &= PAGE_MASK;
@@ -51,10 +53,23 @@ static int change_memory_common(unsigned long addr, int numpages,
 		WARN_ON_ONCE(1);
 	}
 
-	if (start < MODULES_VADDR || start >= MODULES_END)
-		return -EINVAL;
-
-	if (end < MODULES_VADDR || end >= MODULES_END)
+	/*
+	 * Kernel VA mappings are always live, and splitting live section
+	 * mappings into page mappings may cause TLB conflicts. This means
+	 * we have to ensure that changing the permission bits of the range
+	 * we are operating on does not result in such splitting.
+	 *
+	 * Let's restrict ourselves to mappings created by vmalloc (or vmap).
+	 * Those are guaranteed to consist entirely of page mappings, and
+	 * splitting is never needed.
+	 *
+	 * So check whether the [addr, addr + size) interval is entirely
+	 * covered by precisely one VM area that has the VM_ALLOC flag set.
+	 */
+	area = find_vm_area((void *)addr);
+	if (!area ||
+	    end > (unsigned long)area->addr + area->size ||
+	    !(area->flags & VM_ALLOC))
 		return -EINVAL;
 
 	if (!numpages)
diff --git a/arch/arm64/mm/pgd.c b/arch/arm64/mm/pgd.c
index cb3ba1b81..ae11d4e03 100644
--- a/arch/arm64/mm/pgd.c
+++ b/arch/arm64/mm/pgd.c
@@ -46,14 +46,14 @@ void pgd_free(struct mm_struct *mm, pgd_t *pgd)
 		kmem_cache_free(pgd_cache, pgd);
 }
 
-static int __init pgd_cache_init(void)
+void __init pgd_cache_init(void)
 {
+	if (PGD_SIZE == PAGE_SIZE)
+		return;
+
 	/*
 	 * Naturally aligned pgds required by the architecture.
 	 */
-	if (PGD_SIZE != PAGE_SIZE)
-		pgd_cache = kmem_cache_create("pgd_cache", PGD_SIZE, PGD_SIZE,
-					      SLAB_PANIC, NULL);
-	return 0;
+	pgd_cache = kmem_cache_create("pgd_cache", PGD_SIZE, PGD_SIZE,
+				      SLAB_PANIC, NULL);
 }
-core_initcall(pgd_cache_init);
diff --git a/arch/arm64/mm/proc-macros.S b/arch/arm64/mm/proc-macros.S
index d69dffffa..e6a30e126 100644
--- a/arch/arm64/mm/proc-macros.S
+++ b/arch/arm64/mm/proc-macros.S
@@ -64,6 +64,28 @@
 	.endm
 
 /*
+ * Macro to perform a data cache maintenance for the interval
+ * [kaddr, kaddr + size)
+ *
+ * 	op:		operation passed to dc instruction
+ * 	domain:		domain used in dsb instruciton
+ * 	kaddr:		starting virtual address of the region
+ * 	size:		size of the region
+ * 	Corrupts: 	kaddr, size, tmp1, tmp2
+ */
+	.macro dcache_by_line_op op, domain, kaddr, size, tmp1, tmp2
+	dcache_line_size \tmp1, \tmp2
+	add	\size, \kaddr, \size
+	sub	\tmp2, \tmp1, #1
+	bic	\kaddr, \kaddr, \tmp2
+9998:	dc	\op, \kaddr
+	add	\kaddr, \kaddr, \tmp1
+	cmp	\kaddr, \size
+	b.lo	9998b
+	dsb	\domain
+	.endm
+
+/*
  * reset_pmuserenr_el0 - reset PMUSERENR_EL0 if PMUv3 present
  */
 	.macro	reset_pmuserenr_el0, tmpreg
diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S
index b8f04b3f2..c164d2cb3 100644
--- a/arch/arm64/mm/proc.S
+++ b/arch/arm64/mm/proc.S
@@ -140,8 +140,6 @@ ENTRY(cpu_do_switch_mm)
 	ret
 ENDPROC(cpu_do_switch_mm)
 
-	.section ".text.init", #alloc, #execinstr
-
 /*
  *	__cpu_setup
  *