Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 fixes from Will Deacon:
 "The main one is a horrible macro fix for our TLB flushing code which
  resulted in over-invalidation on the MMU notifier path.

  Summary:

   - Fix population of the vmemmap for regions of memory that are
     smaller than a section (128 MiB)

   - Fix range-based TLB over-invalidation when invoked via a MMU
     notifier"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  Fix mmu notifiers for range-based invalidates
  arm64: mm: Populate vmemmap at the page level if not section aligned

Author: torvalds

arch/arm64/include/asm/tlbflush.h

@@ -396,33 +396,35 @@ static inline void arch_tlbbatch_flush(struct arch_tlbflush_unmap_batch *batch)
 #define __flush_tlb_range_op(op, start, pages, stride,			\
 				asid, tlb_level, tlbi_user, lpa2)	\
 do {									\
+	typeof(start) __flush_start = start;				\
+	typeof(pages) __flush_pages = pages;				\
 	int num = 0;							\
 	int scale = 3;							\
 	int shift = lpa2 ? 16 : PAGE_SHIFT;				\
 	unsigned long addr;						\
 									\
-	while (pages > 0) {						\
+	while (__flush_pages > 0) {					\
 		if (!system_supports_tlb_range() ||			\
-		    pages == 1 ||					\
-		    (lpa2 && start != ALIGN(start, SZ_64K))) {		\
-			addr = __TLBI_VADDR(start, asid);		\
+		    __flush_pages == 1 ||				\
+		    (lpa2 && __flush_start != ALIGN(__flush_start, SZ_64K))) {	\
+			addr = __TLBI_VADDR(__flush_start, asid);	\
 			__tlbi_level(op, addr, tlb_level);		\
 			if (tlbi_user)					\
 				__tlbi_user_level(op, addr, tlb_level);	\
-			start += stride;				\
-			pages -= stride >> PAGE_SHIFT;			\
+			__flush_start += stride;			\
+			__flush_pages -= stride >> PAGE_SHIFT;		\
 			continue;					\
 		}							\
 									\
-		num = __TLBI_RANGE_NUM(pages, scale);			\
+		num = __TLBI_RANGE_NUM(__flush_pages, scale);		\
 		if (num >= 0) {						\
-			addr = __TLBI_VADDR_RANGE(start >> shift, asid, \
+			addr = __TLBI_VADDR_RANGE(__flush_start >> shift, asid, \
 						scale, num, tlb_level);	\
 			__tlbi(r##op, addr);				\
 			if (tlbi_user)					\
 				__tlbi_user(r##op, addr);		\
-			start += __TLBI_RANGE_PAGES(num, scale) << PAGE_SHIFT; \
-			pages -= __TLBI_RANGE_PAGES(num, scale);	\
+			__flush_start += __TLBI_RANGE_PAGES(num, scale) << PAGE_SHIFT; \
+			__flush_pages -= __TLBI_RANGE_PAGES(num, scale);\
 		}							\
 		scale--;						\
 	}								\

arch/arm64/mm/mmu.c

@@ -1177,8 +1177,11 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
 		struct vmem_altmap *altmap)
 {
 	WARN_ON((start < VMEMMAP_START) || (end > VMEMMAP_END));
+	/* [start, end] should be within one section */
+	WARN_ON_ONCE(end - start > PAGES_PER_SECTION * sizeof(struct page));
 
-	if (!IS_ENABLED(CONFIG_ARM64_4K_PAGES))
+	if (!IS_ENABLED(CONFIG_ARM64_4K_PAGES) ||
+	    (end - start < PAGES_PER_SECTION * sizeof(struct page)))
 		return vmemmap_populate_basepages(start, end, node, altmap);
 	else
 		return vmemmap_populate_hugepages(start, end, node, altmap);