Merge branch 'akpm' (patches from Andrew)

Merge misc fixes from Andrew Morton:
 "18 patches.

  Subsystems affected by this patch series: mm (hugetlb, compaction,
  vmalloc, shmem, memblock, pagecache, kasan, and hugetlb), mailmap,
  gcov, ubsan, and MAINTAINERS"

* emailed patches from Andrew Morton <[email protected]>:
  MAINTAINERS/.mailmap: use my @kernel.org address
  mm: hugetlb: fix missing put_page in gather_surplus_pages()
  ubsan: implement __ubsan_handle_alignment_assumption
  kasan: make addr_has_metadata() return true for valid addresses
  kasan: add explicit preconditions to kasan_report()
  mm/filemap: add missing mem_cgroup_uncharge() to __add_to_page_cache_locked()
  mailmap: add entries for Manivannan Sadhasivam
  mailmap: fix name/email for Viresh Kumar
  memblock: do not start bottom-up allocations with kernel_end
  mm: thp: fix MADV_REMOVE deadlock on shmem THP
  init/gcov: allow CONFIG_CONSTRUCTORS on UML to fix module gcov
  mm/vmalloc: separate put pages and flush VM flags
  mm, compaction: move high_pfn to the for loop scope
  mm: migrate: do not migrate HugeTLB page whose refcount is one
  mm: hugetlb: remove VM_BUG_ON_PAGE from page_huge_active
  mm: hugetlb: fix a race between isolating and freeing page
  mm: hugetlb: fix a race between freeing and dissolving the page
  mm: hugetlbfs: fix cannot migrate the fallocated HugeTLB page

.mailmap

@@ -199,6 +199,8 @@ Li Yang <[email protected]> <[email protected]>
 Li Yang <[email protected]> <[email protected]>
 Lukasz Luba <[email protected]> <[email protected]>
 Maciej W. Rozycki <[email protected]> <[email protected]>
+Manivannan Sadhasivam <[email protected]> <[email protected]>
+Manivannan Sadhasivam <[email protected]> <[email protected]>
 Marcin Nowakowski <[email protected]> <[email protected]>
 Marc Zyngier <[email protected]> <[email protected]>
 Mark Brown <[email protected]>
@@ -244,6 +246,7 @@ Morten Welinder <[email protected]>
 Morten Welinder <[email protected]>
 Morten Welinder <[email protected]>
 Mythri P K <[email protected]>
+Nathan Chancellor <[email protected]> <[email protected]>
 Nguyen Anh Quynh <[email protected]>
 Nicolas Ferre <[email protected]> <[email protected]>
 Nicolas Pitre <[email protected]> <[email protected]>
@@ -334,6 +337,8 @@ Vinod Koul <[email protected]> <[email protected]>
 Viresh Kumar <[email protected]> <[email protected]>
 Viresh Kumar <[email protected]> <[email protected]>
 Viresh Kumar <[email protected]> <[email protected]>
+Viresh Kumar <[email protected]> <[email protected]>
+Viresh Kumar <[email protected]> <[email protected]>
 Vivien Didelot <[email protected]> <[email protected]>
 Vlad Dogaru <[email protected]> <[email protected]>
 Vladimir Davydov <[email protected]> <[email protected]>

MAINTAINERS

@@ -4304,7 +4304,7 @@ S:	Maintained
 F:	.clang-format
 
 CLANG/LLVM BUILD SUPPORT
-M:	Nathan Chancellor <[email protected]>
+M:	Nathan Chancellor <[email protected]>
 M:	Nick Desaulniers <[email protected]>
 L:	[email protected]
 S:	Supported

fs/hugetlbfs/inode.c

@@ -735,9 +735,10 @@ static long hugetlbfs_fallocate(struct file *file, int mode, loff_t offset,
 
 		mutex_unlock(&hugetlb_fault_mutex_table[hash]);
 
+		set_page_huge_active(page);
 		/*
 		 * unlock_page because locked by add_to_page_cache()
-		 * page_put due to reference from alloc_huge_page()
+		 * put_page() due to reference from alloc_huge_page()
 		 */
 		unlock_page(page);
 		put_page(page);

include/linux/hugetlb.h

@@ -770,6 +770,8 @@ static inline void huge_ptep_modify_prot_commit(struct vm_area_struct *vma,
 }
 #endif
 
+void set_page_huge_active(struct page *page);
+
 #else	/* CONFIG_HUGETLB_PAGE */
 struct hstate {};
 

include/linux/kasan.h

@@ -333,6 +333,13 @@ static inline void *kasan_reset_tag(const void *addr)
 	return (void *)arch_kasan_reset_tag(addr);
 }
 
+/**
+ * kasan_report - print a report about a bad memory access detected by KASAN
+ * @addr: address of the bad access
+ * @size: size of the bad access
+ * @is_write: whether the bad access is a write or a read
+ * @ip: instruction pointer for the accessibility check or the bad access itself
+ */
 bool kasan_report(unsigned long addr, size_t size,
 		bool is_write, unsigned long ip);
 

include/linux/vmalloc.h

@@ -24,7 +24,8 @@ struct notifier_block;		/* in notifier.h */
 #define VM_UNINITIALIZED	0x00000020	/* vm_struct is not fully initialized */
 #define VM_NO_GUARD		0x00000040      /* don't add guard page */
 #define VM_KASAN		0x00000080      /* has allocated kasan shadow memory */
-#define VM_MAP_PUT_PAGES	0x00000100	/* put pages and free array in vfree */
+#define VM_FLUSH_RESET_PERMS	0x00000100	/* reset direct map and flush TLB on unmap, can't be freed in atomic context */
+#define VM_MAP_PUT_PAGES	0x00000200	/* put pages and free array in vfree */
 
 /*
  * VM_KASAN is used slighly differently depending on CONFIG_KASAN_VMALLOC.
@@ -37,12 +38,6 @@ struct notifier_block;		/* in notifier.h */
  * determine which allocations need the module shadow freed.
  */
 
-/*
- * Memory with VM_FLUSH_RESET_PERMS cannot be freed in an interrupt or with
- * vfree_atomic().
- */
-#define VM_FLUSH_RESET_PERMS	0x00000100      /* Reset direct map and flush TLB on unmap */
-
 /* bits [20..32] reserved for arch specific ioremap internals */
 
 /*

init/Kconfig

@@ -76,7 +76,6 @@ config CC_HAS_ASM_INLINE
 
 config CONSTRUCTORS
 	bool
-	depends on !UML
 
 config IRQ_WORK
 	bool

init/main.c

@@ -1066,7 +1066,13 @@ asmlinkage __visible void __init __no_sanitize_address start_kernel(void)
 /* Call all constructor functions linked into the kernel. */
 static void __init do_ctors(void)
 {
-#ifdef CONFIG_CONSTRUCTORS
+/*
+ * For UML, the constructors have already been called by the
+ * normal setup code as it's just a normal ELF binary, so we
+ * cannot do it again - but we do need CONFIG_CONSTRUCTORS
+ * even on UML for modules.
+ */
+#if defined(CONFIG_CONSTRUCTORS) && !defined(CONFIG_UML)
 	ctor_fn_t *fn = (ctor_fn_t *) __ctors_start;
 
 	for (; fn < (ctor_fn_t *) __ctors_end; fn++)

kernel/gcov/Kconfig

@@ -4,7 +4,7 @@ menu "GCOV-based kernel profiling"
 config GCOV_KERNEL
 	bool "Enable gcov-based kernel profiling"
 	depends on DEBUG_FS
-	select CONSTRUCTORS if !UML
+	select CONSTRUCTORS
 	default n
 	help
 	This option enables gcov-based code profiling (e.g. for code coverage

lib/ubsan.c

@@ -427,3 +427,34 @@ void __ubsan_handle_load_invalid_value(void *_data, void *val)
 	ubsan_epilogue();
 }
 EXPORT_SYMBOL(__ubsan_handle_load_invalid_value);
+
+void __ubsan_handle_alignment_assumption(void *_data, unsigned long ptr,
+					 unsigned long align,
+					 unsigned long offset);
+void __ubsan_handle_alignment_assumption(void *_data, unsigned long ptr,
+					 unsigned long align,
+					 unsigned long offset)
+{
+	struct alignment_assumption_data *data = _data;
+	unsigned long real_ptr;
+
+	if (suppress_report(&data->location))
+		return;
+
+	ubsan_prologue(&data->location, "alignment-assumption");
+
+	if (offset)
+		pr_err("assumption of %lu byte alignment (with offset of %lu byte) for pointer of type %s failed",
+		       align, offset, data->type->type_name);
+	else
+		pr_err("assumption of %lu byte alignment for pointer of type %s failed",
+		       align, data->type->type_name);
+
+	real_ptr = ptr - offset;
+	pr_err("%saddress is %lu aligned, misalignment offset is %lu bytes",
+	       offset ? "offset " : "", BIT(real_ptr ? __ffs(real_ptr) : 0),
+	       real_ptr & (align - 1));
+
+	ubsan_epilogue();
+}
+EXPORT_SYMBOL(__ubsan_handle_alignment_assumption);

lib/ubsan.h

@@ -78,6 +78,12 @@ struct invalid_value_data {
 	struct type_descriptor *type;
 };
 
+struct alignment_assumption_data {
+	struct source_location location;
+	struct source_location assumption_location;
+	struct type_descriptor *type;
+};
+
 #if defined(CONFIG_ARCH_SUPPORTS_INT128)
 typedef __int128 s_max;
 typedef unsigned __int128 u_max;

mm/compaction.c

@@ -1342,7 +1342,7 @@ fast_isolate_freepages(struct compact_control *cc)
 {
 	unsigned int limit = min(1U, freelist_scan_limit(cc) >> 1);
 	unsigned int nr_scanned = 0;
-	unsigned long low_pfn, min_pfn, high_pfn = 0, highest = 0;
+	unsigned long low_pfn, min_pfn, highest = 0;
 	unsigned long nr_isolated = 0;
 	unsigned long distance;
 	struct page *page = NULL;
@@ -1387,6 +1387,7 @@ fast_isolate_freepages(struct compact_control *cc)
 		struct page *freepage;
 		unsigned long flags;
 		unsigned int order_scanned = 0;
+		unsigned long high_pfn = 0;
 
 		if (!area->nr_free)
 			continue;

mm/filemap.c

@@ -835,6 +835,7 @@ noinline int __add_to_page_cache_locked(struct page *page,
 	XA_STATE(xas, &mapping->i_pages, offset);
 	int huge = PageHuge(page);
 	int error;
+	bool charged = false;
 
 	VM_BUG_ON_PAGE(!PageLocked(page), page);
 	VM_BUG_ON_PAGE(PageSwapBacked(page), page);
@@ -848,6 +849,7 @@ noinline int __add_to_page_cache_locked(struct page *page,
 		error = mem_cgroup_charge(page, current->mm, gfp);
 		if (error)
 			goto error;
+		charged = true;
 	}
 
 	gfp &= GFP_RECLAIM_MASK;
@@ -896,6 +898,8 @@ noinline int __add_to_page_cache_locked(struct page *page,
 
 	if (xas_error(&xas)) {
 		error = xas_error(&xas);
+		if (charged)
+			mem_cgroup_uncharge(page);
 		goto error;
 	}
 

mm/huge_memory.c

@@ -2202,7 +2202,7 @@ void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
 {
 	spinlock_t *ptl;
 	struct mmu_notifier_range range;
-	bool was_locked = false;
+	bool do_unlock_page = false;
 	pmd_t _pmd;
 
 	mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, vma, vma->vm_mm,
@@ -2218,7 +2218,6 @@ void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
 	VM_BUG_ON(freeze && !page);
 	if (page) {
 		VM_WARN_ON_ONCE(!PageLocked(page));
-		was_locked = true;
 		if (page != pmd_page(*pmd))
 			goto out;
 	}
@@ -2227,19 +2226,29 @@ void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
 	if (pmd_trans_huge(*pmd)) {
 		if (!page) {
 			page = pmd_page(*pmd);
-			if (unlikely(!trylock_page(page))) {
-				get_page(page);
-				_pmd = *pmd;
-				spin_unlock(ptl);
-				lock_page(page);
-				spin_lock(ptl);
-				if (unlikely(!pmd_same(*pmd, _pmd))) {
-					unlock_page(page);
+			/*
+			 * An anonymous page must be locked, to ensure that a
+			 * concurrent reuse_swap_page() sees stable mapcount;
+			 * but reuse_swap_page() is not used on shmem or file,
+			 * and page lock must not be taken when zap_pmd_range()
+			 * calls __split_huge_pmd() while i_mmap_lock is held.
+			 */
+			if (PageAnon(page)) {
+				if (unlikely(!trylock_page(page))) {
+					get_page(page);
+					_pmd = *pmd;
+					spin_unlock(ptl);
+					lock_page(page);
+					spin_lock(ptl);
+					if (unlikely(!pmd_same(*pmd, _pmd))) {
+						unlock_page(page);
+						put_page(page);
+						page = NULL;
+						goto repeat;
+					}
 					put_page(page);
-					page = NULL;
-					goto repeat;
 				}
-				put_page(page);
+				do_unlock_page = true;
 			}
 		}
 		if (PageMlocked(page))
@@ -2249,7 +2258,7 @@ void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
 	__split_huge_pmd_locked(vma, pmd, range.start, freeze);
 out:
 	spin_unlock(ptl);
-	if (!was_locked && page)
+	if (do_unlock_page)
 		unlock_page(page);
 	/*
 	 * No need to double call mmu_notifier->invalidate_range() callback.