Merge branch 'for-next/mm' into for-next/core

* for-next/mm:
  arm64/mm: use lm_alias() with addresses passed to memblock_free()
  mm: arm64: document why pte is not advanced in contpte_ptep_set_access_flags()
  arm64: Expose the end of the linear map in PHYSMEM_END
  arm64: trans_pgd: mark PTEs entries as valid to avoid dead kexec()
  arm64/mm: Delete __init region from memblock.reserved

Author: willdeacon

arch/arm64/include/asm/memory.h

@@ -110,6 +110,8 @@
 #define PAGE_END		(_PAGE_END(VA_BITS_MIN))
 #endif /* CONFIG_KASAN */
 
+#define PHYSMEM_END		__pa(PAGE_END - 1)
+
 #define MIN_THREAD_SHIFT	(14 + KASAN_THREAD_SHIFT)
 
 /*

arch/arm64/mm/contpte.c

@@ -421,6 +421,12 @@ int contpte_ptep_set_access_flags(struct vm_area_struct *vma,
 		ptep = contpte_align_down(ptep);
 		start_addr = addr = ALIGN_DOWN(addr, CONT_PTE_SIZE);
 
+		/*
+		 * We are not advancing entry because __ptep_set_access_flags()
+		 * only consumes access flags from entry. And since we have checked
+		 * for the whole contpte block and returned early, pte_same()
+		 * within __ptep_set_access_flags() is likely false.
+		 */
 		for (i = 0; i < CONT_PTES; i++, ptep++, addr += PAGE_SIZE)
 			__ptep_set_access_flags(vma, addr, ptep, entry, 0);
 

arch/arm64/mm/init.c

@@ -414,8 +414,16 @@ void __init mem_init(void)
 
 void free_initmem(void)
 {
-	free_reserved_area(lm_alias(__init_begin),
-			   lm_alias(__init_end),
+	void *lm_init_begin = lm_alias(__init_begin);
+	void *lm_init_end = lm_alias(__init_end);
+
+	WARN_ON(!IS_ALIGNED((unsigned long)lm_init_begin, PAGE_SIZE));
+	WARN_ON(!IS_ALIGNED((unsigned long)lm_init_end, PAGE_SIZE));
+
+	/* Delete __init region from memblock.reserved. */
+	memblock_free(lm_init_begin, lm_init_end - lm_init_begin);
+
+	free_reserved_area(lm_init_begin, lm_init_end,
 			   POISON_FREE_INITMEM, "unused kernel");
 	/*
 	 * Unmap the __init region but leave the VM area in place. This

arch/arm64/mm/trans_pgd.c

@@ -42,14 +42,16 @@ static void _copy_pte(pte_t *dst_ptep, pte_t *src_ptep, unsigned long addr)
 		 * the temporary mappings we use during restore.
 		 */
 		__set_pte(dst_ptep, pte_mkwrite_novma(pte));
-	} else if ((debug_pagealloc_enabled() ||
-		   is_kfence_address((void *)addr)) && !pte_none(pte)) {
+	} else if (!pte_none(pte)) {
 		/*
 		 * debug_pagealloc will removed the PTE_VALID bit if
 		 * the page isn't in use by the resume kernel. It may have
 		 * been in use by the original kernel, in which case we need
 		 * to put it back in our copy to do the restore.
 		 *
+		 * Other cases include kfence / vmalloc / memfd_secret which
+		 * may call `set_direct_map_invalid_noflush()`.
+		 *
 		 * Before marking this entry valid, check the pfn should
 		 * be mapped.
 		 */