Merge branch 'akpm' (patches from Andrew)

Merge misc fixes from Andrew Morton:
 "11 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  kvm, mm: account shadow page tables to kmemcg
  zswap: re-check zswap_is_full() after do zswap_shrink()
  include/linux/eventfd.h: include linux/errno.h
  mm: fix vma_is_anonymous() false-positives
  mm: use vma_init() to initialize VMAs on stack and data segments
  mm: introduce vma_init()
  mm: fix exports that inadvertently make put_page() EXPORT_SYMBOL_GPL
  ipc/sem.c: prevent queue.status tearing in semop
  mm: disallow mappings that conflict for devm_memremap_pages()
  kasan: only select SLUB_DEBUG with SYSFS=y
  delayacct: fix crash in delayacct_blkio_end() after delayacct init failure

arch/arm/kernel/process.c

@@ -338,6 +338,7 @@ static struct vm_area_struct gate_vma = {
 
 static int __init gate_vma_init(void)
 {
+	vma_init(&gate_vma, NULL);
 	gate_vma.vm_page_prot = PAGE_READONLY_EXEC;
 	return 0;
 }

arch/arm/mach-rpc/ecard.c

@@ -237,8 +237,8 @@ static void ecard_init_pgtables(struct mm_struct *mm)
 
 	memcpy(dst_pgd, src_pgd, sizeof(pgd_t) * (EASI_SIZE / PGDIR_SIZE));
 
+	vma_init(&vma, mm);
 	vma.vm_flags = VM_EXEC;
-	vma.vm_mm = mm;
 
 	flush_tlb_range(&vma, IO_START, IO_START + IO_SIZE);
 	flush_tlb_range(&vma, EASI_START, EASI_START + EASI_SIZE);

arch/arm64/include/asm/tlb.h

@@ -37,7 +37,9 @@ static inline void __tlb_remove_table(void *_table)
 
 static inline void tlb_flush(struct mmu_gather *tlb)
 {
-	struct vm_area_struct vma = { .vm_mm = tlb->mm, };
+	struct vm_area_struct vma;
+
+	vma_init(&vma, tlb->mm);
 
 	/*
 	 * The ASID allocator will either invalidate the ASID or mark

arch/arm64/mm/hugetlbpage.c

@@ -108,11 +108,13 @@ static pte_t get_clear_flush(struct mm_struct *mm,
 			     unsigned long pgsize,
 			     unsigned long ncontig)
 {
-	struct vm_area_struct vma = { .vm_mm = mm };
+	struct vm_area_struct vma;
 	pte_t orig_pte = huge_ptep_get(ptep);
 	bool valid = pte_valid(orig_pte);
 	unsigned long i, saddr = addr;
 
+	vma_init(&vma, mm);
+
 	for (i = 0; i < ncontig; i++, addr += pgsize, ptep++) {
 		pte_t pte = ptep_get_and_clear(mm, addr, ptep);
 
@@ -145,9 +147,10 @@ static void clear_flush(struct mm_struct *mm,
 			     unsigned long pgsize,
 			     unsigned long ncontig)
 {
-	struct vm_area_struct vma = { .vm_mm = mm };
+	struct vm_area_struct vma;
 	unsigned long i, saddr = addr;
 
+	vma_init(&vma, mm);
 	for (i = 0; i < ncontig; i++, addr += pgsize, ptep++)
 		pte_clear(mm, addr, ptep);
 

arch/ia64/include/asm/tlb.h

@@ -120,7 +120,7 @@ ia64_tlb_flush_mmu_tlbonly(struct mmu_gather *tlb, unsigned long start, unsigned
 		 */
 		struct vm_area_struct vma;
 
-		vma.vm_mm = tlb->mm;
+		vma_init(&vma, tlb->mm);
 		/* flush the address range from the tlb: */
 		flush_tlb_range(&vma, start, end);
 		/* now flush the virt. page-table area mapping the address range: */

arch/ia64/mm/init.c

@@ -273,7 +273,7 @@ static struct vm_area_struct gate_vma;
 
 static int __init gate_vma_init(void)
 {
-	gate_vma.vm_mm = NULL;
+	vma_init(&gate_vma, NULL);
 	gate_vma.vm_start = FIXADDR_USER_START;
 	gate_vma.vm_end = FIXADDR_USER_END;
 	gate_vma.vm_flags = VM_READ | VM_MAYREAD | VM_EXEC | VM_MAYEXEC;

arch/x86/kvm/mmu.c

@@ -890,7 +890,7 @@ static int mmu_topup_memory_cache_page(struct kvm_mmu_memory_cache *cache,
 	if (cache->nobjs >= min)
 		return 0;
 	while (cache->nobjs < ARRAY_SIZE(cache->objects)) {
-		page = (void *)__get_free_page(GFP_KERNEL);
+		page = (void *)__get_free_page(GFP_KERNEL_ACCOUNT);
 		if (!page)
 			return -ENOMEM;
 		cache->objects[cache->nobjs++] = page;

arch/x86/um/mem_32.c

@@ -16,7 +16,7 @@ static int __init gate_vma_init(void)
 	if (!FIXADDR_USER_START)
 		return 0;
 
-	gate_vma.vm_mm = NULL;
+	vma_init(&gate_vma, NULL);
 	gate_vma.vm_start = FIXADDR_USER_START;
 	gate_vma.vm_end = FIXADDR_USER_END;
 	gate_vma.vm_flags = VM_READ | VM_MAYREAD | VM_EXEC | VM_MAYEXEC;

drivers/char/mem.c

@@ -708,6 +708,7 @@ static int mmap_zero(struct file *file, struct vm_area_struct *vma)
 #endif
 	if (vma->vm_flags & VM_SHARED)
 		return shmem_zero_setup(vma);
+	vma_set_anonymous(vma);
 	return 0;
 }
 

fs/exec.c

@@ -293,6 +293,7 @@ static int __bprm_mm_init(struct linux_binprm *bprm)
 	bprm->vma = vma = vm_area_alloc(mm);
 	if (!vma)
 		return -ENOMEM;
+	vma_set_anonymous(vma);
 
 	if (down_write_killable(&mm->mmap_sem)) {
 		err = -EINTR;

fs/hugetlbfs/inode.c

@@ -411,6 +411,7 @@ static void remove_inode_hugepages(struct inode *inode, loff_t lstart,
 	bool truncate_op = (lend == LLONG_MAX);
 
 	memset(&pseudo_vma, 0, sizeof(struct vm_area_struct));
+	vma_init(&pseudo_vma, current->mm);
 	pseudo_vma.vm_flags = (VM_HUGETLB | VM_MAYSHARE | VM_SHARED);
 	pagevec_init(&pvec);
 	next = start;
@@ -595,6 +596,7 @@ static long hugetlbfs_fallocate(struct file *file, int mode, loff_t offset,
 	 * as input to create an allocation policy.
 	 */
 	memset(&pseudo_vma, 0, sizeof(struct vm_area_struct));
+	vma_init(&pseudo_vma, mm);
 	pseudo_vma.vm_flags = (VM_HUGETLB | VM_MAYSHARE | VM_SHARED);
 	pseudo_vma.vm_file = file;
 

include/linux/delayacct.h

@@ -124,7 +124,7 @@ static inline void delayacct_blkio_start(void)
 
 static inline void delayacct_blkio_end(struct task_struct *p)
 {
-	if (current->delays)
+	if (p->delays)
 		__delayacct_blkio_end(p);
 	delayacct_clear_flag(DELAYACCT_PF_BLKIO);
 }

include/linux/eventfd.h

@@ -11,6 +11,7 @@
 
 #include <linux/fcntl.h>
 #include <linux/wait.h>
+#include <linux/err.h>
 
 /*
  * CAREFUL: Check include/uapi/asm-generic/fcntl.h when defining

include/linux/mm.h

@@ -452,6 +452,20 @@ struct vm_operations_struct {
 					  unsigned long addr);
 };
 
+static inline void vma_init(struct vm_area_struct *vma, struct mm_struct *mm)
+{
+	static const struct vm_operations_struct dummy_vm_ops = {};
+
+	vma->vm_mm = mm;
+	vma->vm_ops = &dummy_vm_ops;
+	INIT_LIST_HEAD(&vma->anon_vma_chain);
+}
+
+static inline void vma_set_anonymous(struct vm_area_struct *vma)
+{
+	vma->vm_ops = NULL;
+}
+
 struct mmu_gather;
 struct inode;
 

ipc/sem.c

@@ -2118,7 +2118,7 @@ static long do_semtimedop(int semid, struct sembuf __user *tsops,
 	}
 
 	do {
-		queue.status = -EINTR;
+		WRITE_ONCE(queue.status, -EINTR);
 		queue.sleeper = current;
 
 		__set_current_state(TASK_INTERRUPTIBLE);

kernel/fork.c

@@ -312,10 +312,8 @@ struct vm_area_struct *vm_area_alloc(struct mm_struct *mm)
 {
 	struct vm_area_struct *vma = kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL);
 
-	if (vma) {
-		vma->vm_mm = mm;
-		INIT_LIST_HEAD(&vma->anon_vma_chain);
-	}
+	if (vma)
+		vma_init(vma, mm);
 	return vma;
 }
 

kernel/memremap.c

@@ -176,10 +176,27 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
 	unsigned long pfn, pgoff, order;
 	pgprot_t pgprot = PAGE_KERNEL;
 	int error, nid, is_ram;
+	struct dev_pagemap *conflict_pgmap;
 
 	align_start = res->start & ~(SECTION_SIZE - 1);
 	align_size = ALIGN(res->start + resource_size(res), SECTION_SIZE)
 		- align_start;
+	align_end = align_start + align_size - 1;
+
+	conflict_pgmap = get_dev_pagemap(PHYS_PFN(align_start), NULL);
+	if (conflict_pgmap) {
+		dev_WARN(dev, "Conflicting mapping in same section\n");
+		put_dev_pagemap(conflict_pgmap);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	conflict_pgmap = get_dev_pagemap(PHYS_PFN(align_end), NULL);
+	if (conflict_pgmap) {
+		dev_WARN(dev, "Conflicting mapping in same section\n");
+		put_dev_pagemap(conflict_pgmap);
+		return ERR_PTR(-ENOMEM);
+	}
+
 	is_ram = region_intersects(align_start, align_size,
 		IORESOURCE_SYSTEM_RAM, IORES_DESC_NONE);
 
@@ -199,7 +216,6 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
 
 	mutex_lock(&pgmap_lock);
 	error = 0;
-	align_end = align_start + align_size - 1;
 
 	foreach_order_pgoff(res, order, pgoff) {
 		error = __radix_tree_insert(&pgmap_radix,
@@ -305,7 +321,7 @@ EXPORT_SYMBOL_GPL(get_dev_pagemap);
 
 #ifdef CONFIG_DEV_PAGEMAP_OPS
 DEFINE_STATIC_KEY_FALSE(devmap_managed_key);
-EXPORT_SYMBOL_GPL(devmap_managed_key);
+EXPORT_SYMBOL(devmap_managed_key);
 static atomic_t devmap_enable;
 
 /*
@@ -346,5 +362,5 @@ void __put_devmap_managed_page(struct page *page)
 	} else if (!count)
 		__put_page(page);
 }
-EXPORT_SYMBOL_GPL(__put_devmap_managed_page);
+EXPORT_SYMBOL(__put_devmap_managed_page);
 #endif /* CONFIG_DEV_PAGEMAP_OPS */

lib/Kconfig.kasan

@@ -5,7 +5,7 @@ if HAVE_ARCH_KASAN
 
 config KASAN
 	bool "KASan: runtime memory debugger"
-	depends on SLUB || (SLAB && !DEBUG_SLAB)
+	depends on (SLUB && SYSFS) || (SLAB && !DEBUG_SLAB)
 	select SLUB_DEBUG if SLUB
 	select CONSTRUCTORS
 	select STACKDEPOT

mm/mempolicy.c

@@ -2505,6 +2505,7 @@ void mpol_shared_policy_init(struct shared_policy *sp, struct mempolicy *mpol)
 
 		/* Create pseudo-vma that contains just the policy */
 		memset(&pvma, 0, sizeof(struct vm_area_struct));
+		vma_init(&pvma, NULL);
 		pvma.vm_end = TASK_SIZE;	/* policy covers entire file */
 		mpol_set_shared_policy(sp, &pvma, new); /* adds ref */
 

mm/mmap.c

@@ -1778,6 +1778,8 @@ unsigned long mmap_region(struct file *file, unsigned long addr,
 		error = shmem_zero_setup(vma);
 		if (error)
 			goto free_vma;
+	} else {
+		vma_set_anonymous(vma);
 	}
 
 	vma_link(mm, vma, prev, rb_link, rb_parent);
@@ -2983,6 +2985,7 @@ static int do_brk_flags(unsigned long addr, unsigned long len, unsigned long fla
 		return -ENOMEM;
 	}
 
+	vma_set_anonymous(vma);
 	vma->vm_start = addr;
 	vma->vm_end = addr + len;
 	vma->vm_pgoff = pgoff;

mm/nommu.c

@@ -1145,6 +1145,8 @@ static int do_mmap_private(struct vm_area_struct *vma,
 		if (ret < len)
 			memset(base + ret, 0, len - ret);
 
+	} else {
+		vma_set_anonymous(vma);
 	}
 
 	return 0;

mm/shmem.c

@@ -1421,6 +1421,7 @@ static void shmem_pseudo_vma_init(struct vm_area_struct *vma,
 {
 	/* Create a pseudo vma that just contains the policy */
 	memset(vma, 0, sizeof(*vma));
+	vma_init(vma, NULL);
 	/* Bias interleave by inode number to distribute better across nodes */
 	vma->vm_pgoff = index + info->vfs_inode.i_ino;
 	vma->vm_policy = mpol_shared_policy_lookup(&info->policy, index);

mm/zswap.c

@@ -1026,6 +1026,15 @@ static int zswap_frontswap_store(unsigned type, pgoff_t offset,
 			ret = -ENOMEM;
 			goto reject;
 		}
+
+		/* A second zswap_is_full() check after
+		 * zswap_shrink() to make sure it's now
+		 * under the max_pool_percent
+		 */
+		if (zswap_is_full()) {
+			ret = -ENOMEM;
+			goto reject;
+		}
 	}
 
 	/* allocate entry */