Merge branch 'akpm' (patches from Andrew)

Merge more updates from Andrew Morton:

- MM remainders

- various misc things

- kcov updates

* emailed patches from Andrew Morton <[e-mail]>: (27 commits)
lib/test_printf.c: call wait_for_random_bytes() before plain %p tests
hexagon: drop the unused variable zero_page_mask
hexagon: fix printk format warning in setup.c
mm: fix oom_kill event handling
treewide: use PHYS_ADDR_MAX to avoid type casting ULLONG_MAX
mm: use octal not symbolic permissions
ipc: use new return type vm_fault_t
sysvipc/sem: mitigate semnum index against spectre v1
fault-injection: reorder config entries
arm: port KCOV to arm
sched/core / kcov: avoid kcov_area during task switch
kcov: prefault the kcov_area
kcov: ensure irq code sees a valid area
kernel/relay.c: change return type to vm_fault_t
exofs: avoid VLA in structures
coredump: fix spam with zero VMA process
fat: use fat_fs_error() instead of BUG_ON() in __fat_get_block()
proc: skip branch in /proc/*/* lookup
mremap: remove LATENCY_LIMIT from mremap to reduce the number of TLB shootdowns
mm/memblock: add missing include <linux/bootmem.h>
...

arch/arm/Kconfig

···
 	select ARCH_HAS_DEVMEM_IS_ALLOWED
 	select ARCH_HAS_ELF_RANDOMIZE
 	select ARCH_HAS_FORTIFY_SOURCE
+	select ARCH_HAS_KCOV
 	select ARCH_HAS_PTE_SPECIAL if ARM_LPAE
-	select ARCH_HAS_SET_MEMORY
 	select ARCH_HAS_PHYS_TO_DMA
+	select ARCH_HAS_SET_MEMORY
 	select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL
 	select ARCH_HAS_STRICT_MODULE_RWX if MMU
 	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST

arch/arm/boot/compressed/Makefile

···
 
 GCOV_PROFILE		:= n
 
+# Prevents link failures: __sanitizer_cov_trace_pc() is not linked in.
+KCOV_INSTRUMENT		:= n
+
 #
 # Architecture dependencies
 #

arch/arm/kvm/hyp/Makefile

···
 obj-$(CONFIG_KVM_ARM_HOST) += switch.o
 CFLAGS_switch.o		   += $(CFLAGS_ARMV7VE)
 obj-$(CONFIG_KVM_ARM_HOST) += s2-setup.o
+
+# KVM code is run at a different exception code with a different map, so
+# compiler instrumentation that inserts callbacks or checks into the code may
+# cause crashes. Just disable it.
+GCOV_PROFILE	:= n
+KASAN_SANITIZE	:= n
+UBSAN_SANITIZE	:= n
+KCOV_INSTRUMENT	:= n

arch/arm/vdso/Makefile

···
 # Disable gcov profiling for VDSO code
 GCOV_PROFILE := n
 
+# Prevents link failures: __sanitizer_cov_trace_pc() is not linked in.
+KCOV_INSTRUMENT := n
+
 # Force dependency
 $(obj)/vdso.o : $(obj)/vdso.so
 

arch/arm64/mm/init.c

···
 }
 #endif
 
-static phys_addr_t memory_limit = (phys_addr_t)ULLONG_MAX;
+static phys_addr_t memory_limit = PHYS_ADDR_MAX;
 
 /*
  * Limit the memory size that was specified via FDT.
···
 	 * high up in memory, add back the kernel region that must be accessible
 	 * via the linear mapping.
 	 */
-	if (memory_limit != (phys_addr_t)ULLONG_MAX) {
+	if (memory_limit != PHYS_ADDR_MAX) {
 		memblock_mem_limit_remove_map(memory_limit);
 		memblock_add(__pa_symbol(_text), (u64)(_end - _text));
 	}
···
  */
 static int dump_mem_limit(struct notifier_block *self, unsigned long v, void *p)
 {
-	if (memory_limit != (phys_addr_t)ULLONG_MAX) {
+	if (memory_limit != PHYS_ADDR_MAX) {
 		pr_emerg("Memory Limit: %llu MB\n", memory_limit >> 20);
 	} else {
 		pr_emerg("Memory Limit: none\n");

arch/hexagon/include/asm/pgtable.h

···
 
 /* A handy thing to have if one has the RAM. Declared in head.S */
 extern unsigned long empty_zero_page;
-extern unsigned long zero_page_mask;
 
 /*
  * The PTE model described here is that of the Hexagon Virtual Machine,

arch/hexagon/kernel/setup.c

···
 	 */
 	__vmsetvec(_K_VM_event_vector);
 
-	printk(KERN_INFO "PHYS_OFFSET=0x%08x\n", PHYS_OFFSET);
+	printk(KERN_INFO "PHYS_OFFSET=0x%08lx\n", PHYS_OFFSET);
 
 	/*
 	 * Simulator has a few differences from the hardware.

arch/hexagon/mm/init.c

···
 /*  Set as variable to limit PMD copies  */
 int max_kernel_seg = 0x303;
 
-/*  think this should be (page_size-1) the way it's used...*/
-unsigned long zero_page_mask;
-
 /*  indicate pfn's of high memory  */
 unsigned long highstart_pfn, highend_pfn;
 

arch/mips/kernel/setup.c

···
 	 * If the region reaches the top of the physical address space, adjust
 	 * the size slightly so that (start + size) doesn't overflow
 	 */
-	if (start + size - 1 == (phys_addr_t)ULLONG_MAX)
+	if (start + size - 1 == PHYS_ADDR_MAX)
 		--size;
 
 	/* Sanity check */
···
 	unsigned long reserved_end;
 	unsigned long mapstart = ~0UL;
 	unsigned long bootmap_size;
-	phys_addr_t ramstart = (phys_addr_t)ULLONG_MAX;
+	phys_addr_t ramstart = PHYS_ADDR_MAX;
 	bool bootmap_valid = false;
 	int i;
 

arch/powerpc/mm/mem.c

···
 	/* Place all memblock_regions in the same node and merge contiguous
 	 * memblock_regions
 	 */
-	memblock_set_node(0, (phys_addr_t)ULLONG_MAX, &memblock.memory, 0);
+	memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0);
 }
 
 void __init initmem_init(void)

arch/sparc/mm/init_64.c

···
 	       (top_of_ram - total_ram) >> 20);
 
 	init_node_masks_nonnuma();
-	memblock_set_node(0, (phys_addr_t)ULLONG_MAX, &memblock.memory, 0);
+	memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0);
 	allocate_node_data(0);
 	node_set_online(0);
 }

arch/x86/mm/init.c

···
  */
 int devmem_is_allowed(unsigned long pagenr)
 {
-	if (page_is_ram(pagenr)) {
+	if (region_intersects(PFN_PHYS(pagenr), PAGE_SIZE,
+				IORESOURCE_SYSTEM_RAM, IORES_DESC_NONE)
+			!= REGION_DISJOINT) {
 		/*
 		 * For disallowed memory regions in the low 1MB range,
 		 * request that the page be shown as all zeros.

arch/x86/mm/init_32.c

···
 	high_memory = (void *) __va(max_low_pfn * PAGE_SIZE - 1) + 1;
 #endif
 
-	memblock_set_node(0, (phys_addr_t)ULLONG_MAX, &memblock.memory, 0);
+	memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0);
 	sparse_memory_present_with_active_regions(0);
 
 #ifdef CONFIG_FLATMEM

arch/x86/mm/init_64.c

···
 #ifndef CONFIG_NUMA
 void __init initmem_init(void)
 {
-	memblock_set_node(0, (phys_addr_t)ULLONG_MAX, &memblock.memory, 0);
+	memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0);
 }
 #endif
 

drivers/firmware/efi/arm-init.c

···
 	 * uses its own memory map instead.
 	 */
 	memblock_dump_all();
-	memblock_remove(0, (phys_addr_t)ULLONG_MAX);
+	memblock_remove(0, PHYS_ADDR_MAX);
 
 	for_each_efi_memory_desc(md) {
 		paddr = md->phys_addr;

drivers/remoteproc/qcom_q6v5_pil.c

···
 	struct elf32_hdr *ehdr;
 	phys_addr_t mpss_reloc;
 	phys_addr_t boot_addr;
-	phys_addr_t min_addr = (phys_addr_t)ULLONG_MAX;
+	phys_addr_t min_addr = PHYS_ADDR_MAX;
 	phys_addr_t max_addr = 0;
 	bool relocate = false;
 	char seg_name[10];

drivers/soc/qcom/mdt_loader.c

···
 	const struct elf32_phdr *phdrs;
 	const struct elf32_phdr *phdr;
 	const struct elf32_hdr *ehdr;
-	phys_addr_t min_addr = (phys_addr_t)ULLONG_MAX;
+	phys_addr_t min_addr = PHYS_ADDR_MAX;
 	phys_addr_t max_addr = 0;
 	int i;
 
···
 	const struct elf32_hdr *ehdr;
 	const struct firmware *seg_fw;
 	phys_addr_t mem_reloc;
-	phys_addr_t min_addr = (phys_addr_t)ULLONG_MAX;
+	phys_addr_t min_addr = PHYS_ADDR_MAX;
 	phys_addr_t max_addr = 0;
 	size_t fw_name_len;
 	ssize_t offset;

fs/binfmt_elf.c

···
 	if (size >= MAX_FILE_NOTE_SIZE) /* paranoia check */
 		return -EINVAL;
 	size = round_up(size, PAGE_SIZE);
-	data = vmalloc(size);
-	if (!data)
+	data = kvmalloc(size, GFP_KERNEL);
+	if (ZERO_OR_NULL_PTR(data))
 		return -ENOMEM;
 
 	start_end_ofs = data + 2;
···
 		filename = file_path(file, name_curpos, remaining);
 		if (IS_ERR(filename)) {
 			if (PTR_ERR(filename) == -ENAMETOOLONG) {
-				vfree(data);
+				kvfree(data);
 				size = size * 5 / 4;
 				goto alloc;
 			}
···
 		kfree(t);
 	}
 	kfree(info->psinfo.data);
-	vfree(info->files.data);
+	kvfree(info->files.data);
 }
 
 #else
···
 
 	/* Free data possibly allocated by fill_files_note(): */
 	if (info->notes_files)
-		vfree(info->notes_files->data);
+		kvfree(info->notes_files->data);
 
 	kfree(info->prstatus);
 	kfree(info->psinfo);
···
 
 	if (segs - 1 > ULONG_MAX / sizeof(*vma_filesz))
 		goto end_coredump;
-	vma_filesz = vmalloc(array_size(sizeof(*vma_filesz), (segs - 1)));
-	if (!vma_filesz)
+	vma_filesz = kvmalloc(array_size(sizeof(*vma_filesz), (segs - 1)),
+			      GFP_KERNEL);
+	if (ZERO_OR_NULL_PTR(vma_filesz))
 		goto end_coredump;
 
 	for (i = 0, vma = first_vma(current, gate_vma); vma != NULL;
···
 cleanup:
 	free_note_info(&info);
 	kfree(shdr4extnum);
-	vfree(vma_filesz);
+	kvfree(vma_filesz);
 	kfree(phdr4note);
 	kfree(elf);
 out:

fs/exofs/ore.c

···
 			struct ore_io_state **pios)
 {
 	struct ore_io_state *ios;
-	struct page **pages;
-	struct osd_sg_entry *sgilist;
+	size_t size_ios, size_extra, size_total;
+	void *ios_extra;
+
+	/*
+	 * The desired layout looks like this, with the extra_allocation
+	 * items pointed at from fields within ios or per_dev:
+
 	struct __alloc_all_io_state {
 		struct ore_io_state ios;
 		struct ore_per_dev_state per_dev[numdevs];
 		union {
 			struct osd_sg_entry sglist[sgs_per_dev * numdevs];
 			struct page *pages[num_par_pages];
-		};
-	} *_aios;
+		} extra_allocation;
+	} whole_allocation;
 
-	if (likely(sizeof(*_aios) <= PAGE_SIZE)) {
-		_aios = kzalloc(sizeof(*_aios), GFP_KERNEL);
-		if (unlikely(!_aios)) {
-			ORE_DBGMSG("Failed kzalloc bytes=%zd\n",
-				   sizeof(*_aios));
+	*/
+
+	/* This should never happen, so abort early if it ever does. */
+	if (sgs_per_dev && num_par_pages) {
+		ORE_DBGMSG("Tried to use both pages and sglist\n");
+		*pios = NULL;
+		return -EINVAL;
+	}
+
+	if (numdevs > (INT_MAX - sizeof(*ios)) /
+		       sizeof(struct ore_per_dev_state))
+		return -ENOMEM;
+	size_ios = sizeof(*ios) + sizeof(struct ore_per_dev_state) * numdevs;
+
+	if (sgs_per_dev * numdevs > INT_MAX / sizeof(struct osd_sg_entry))
+		return -ENOMEM;
+	if (num_par_pages > INT_MAX / sizeof(struct page *))
+		return -ENOMEM;
+	size_extra = max(sizeof(struct osd_sg_entry) * (sgs_per_dev * numdevs),
+			 sizeof(struct page *) * num_par_pages);
+
+	size_total = size_ios + size_extra;
+
+	if (likely(size_total <= PAGE_SIZE)) {
+		ios = kzalloc(size_total, GFP_KERNEL);
+		if (unlikely(!ios)) {
+			ORE_DBGMSG("Failed kzalloc bytes=%zd\n", size_total);
 			*pios = NULL;
 			return -ENOMEM;
 		}
-		pages = num_par_pages ? _aios->pages : NULL;
-		sgilist = sgs_per_dev ? _aios->sglist : NULL;
-		ios = &_aios->ios;
+		ios_extra = (char *)ios + size_ios;
 	} else {
-		struct __alloc_small_io_state {
-			struct ore_io_state ios;
-			struct ore_per_dev_state per_dev[numdevs];
-		} *_aio_small;
-		union __extra_part {
-			struct osd_sg_entry sglist[sgs_per_dev * numdevs];
-			struct page *pages[num_par_pages];
-		} *extra_part;
-
-		_aio_small = kzalloc(sizeof(*_aio_small), GFP_KERNEL);
-		if (unlikely(!_aio_small)) {
+		ios = kzalloc(size_ios, GFP_KERNEL);
+		if (unlikely(!ios)) {
 			ORE_DBGMSG("Failed alloc first part bytes=%zd\n",
-				   sizeof(*_aio_small));
+				   size_ios);
 			*pios = NULL;
 			return -ENOMEM;
 		}
-		extra_part = kzalloc(sizeof(*extra_part), GFP_KERNEL);
-		if (unlikely(!extra_part)) {
+		ios_extra = kzalloc(size_extra, GFP_KERNEL);
+		if (unlikely(!ios_extra)) {
 			ORE_DBGMSG("Failed alloc second part bytes=%zd\n",
-				   sizeof(*extra_part));
-			kfree(_aio_small);
+				   size_extra);
+			kfree(ios);
 			*pios = NULL;
 			return -ENOMEM;
 		}
 
-		pages = num_par_pages ? extra_part->pages : NULL;
-		sgilist = sgs_per_dev ? extra_part->sglist : NULL;
 		/* In this case the per_dev[0].sgilist holds the pointer to
 		 * be freed
 		 */
-		ios = &_aio_small->ios;
 		ios->extra_part_alloc = true;
 	}
 
-	if (pages) {
-		ios->parity_pages = pages;
+	if (num_par_pages) {
+		ios->parity_pages = ios_extra;
 		ios->max_par_pages = num_par_pages;
 	}
-	if (sgilist) {
+	if (sgs_per_dev) {
+		struct osd_sg_entry *sgilist = ios_extra;
 		unsigned d;
 
 		for (d = 0; d < numdevs; ++d) {

fs/exofs/ore_raid.c

···
 {
 	struct __stripe_pages_2d *sp2d;
 	unsigned data_devs = group_width - parity;
+
+	/*
+	 * Desired allocation layout is, though when larger than PAGE_SIZE,
+	 * each struct __alloc_1p_arrays is separately allocated:
+
 	struct _alloc_all_bytes {
 		struct __alloc_stripe_pages_2d {
 			struct __stripe_pages_2d sp2d;
···
 			char page_is_read[data_devs];
 		} __a1pa[pages_in_unit];
 	} *_aab;
+
 	struct __alloc_1p_arrays *__a1pa;
 	struct __alloc_1p_arrays *__a1pa_end;
-	const unsigned sizeof__a1pa = sizeof(_aab->__a1pa[0]);
+
+	*/
+
+	char *__a1pa;
+	char *__a1pa_end;
+
+	const size_t sizeof_stripe_pages_2d =
+		sizeof(struct __stripe_pages_2d) +
+		sizeof(struct __1_page_stripe) * pages_in_unit;
+	const size_t sizeof__a1pa =
+		ALIGN(sizeof(struct page *) * (2 * group_width) + data_devs,
+		      sizeof(void *));
+	const size_t sizeof__a1pa_arrays = sizeof__a1pa * pages_in_unit;
+	const size_t alloc_total = sizeof_stripe_pages_2d +
+				   sizeof__a1pa_arrays;
+
 	unsigned num_a1pa, alloc_size, i;
 
 	/* FIXME: check these numbers in ore_verify_layout */
-	BUG_ON(sizeof(_aab->__asp2d) > PAGE_SIZE);
+	BUG_ON(sizeof_stripe_pages_2d > PAGE_SIZE);
 	BUG_ON(sizeof__a1pa > PAGE_SIZE);
 
-	if (sizeof(*_aab) > PAGE_SIZE) {
-		num_a1pa = (PAGE_SIZE - sizeof(_aab->__asp2d)) / sizeof__a1pa;
-		alloc_size = sizeof(_aab->__asp2d) + sizeof__a1pa * num_a1pa;
+	/*
+	 * If alloc_total would be larger than PAGE_SIZE, only allocate
+	 * as many a1pa items as would fill the rest of the page, instead
+	 * of the full pages_in_unit count.
+	 */
+	if (alloc_total > PAGE_SIZE) {
+		num_a1pa = (PAGE_SIZE - sizeof_stripe_pages_2d) / sizeof__a1pa;
+		alloc_size = sizeof_stripe_pages_2d + sizeof__a1pa * num_a1pa;
 	} else {
 		num_a1pa = pages_in_unit;
-		alloc_size = sizeof(*_aab);
+		alloc_size = alloc_total;
 	}
 
-	_aab = kzalloc(alloc_size, GFP_KERNEL);
-	if (unlikely(!_aab)) {
+	*psp2d = sp2d = kzalloc(alloc_size, GFP_KERNEL);
+	if (unlikely(!sp2d)) {
 		ORE_DBGMSG("!! Failed to alloc sp2d size=%d\n", alloc_size);
 		return -ENOMEM;
 	}
+	/* From here Just call _sp2d_free */
 
-	sp2d = &_aab->__asp2d.sp2d;
-	*psp2d = sp2d; /* From here Just call _sp2d_free */
+	/* Find start of a1pa area. */
+	__a1pa = (char *)sp2d + sizeof_stripe_pages_2d;
+	/* Find end of the _allocated_ a1pa area. */
+	__a1pa_end = __a1pa + alloc_size;
 
-	__a1pa = _aab->__a1pa;
-	__a1pa_end = __a1pa + num_a1pa;
-
+	/* Allocate additionally needed a1pa items in PAGE_SIZE chunks. */
 	for (i = 0; i < pages_in_unit; ++i) {
+		struct __1_page_stripe *stripe = &sp2d->_1p_stripes[i];
+
 		if (unlikely(__a1pa >= __a1pa_end)) {
 			num_a1pa = min_t(unsigned, PAGE_SIZE / sizeof__a1pa,
 							pages_in_unit - i);
+			alloc_size = sizeof__a1pa * num_a1pa;
 
-			__a1pa = kcalloc(num_a1pa, sizeof__a1pa, GFP_KERNEL);
+			__a1pa = kzalloc(alloc_size, GFP_KERNEL);
 			if (unlikely(!__a1pa)) {
 				ORE_DBGMSG("!! Failed to _alloc_1p_arrays=%d\n",
 					   num_a1pa);
 				return -ENOMEM;
 			}
-			__a1pa_end = __a1pa + num_a1pa;
+			__a1pa_end = __a1pa + alloc_size;
 			/* First *pages is marked for kfree of the buffer */
-			sp2d->_1p_stripes[i].alloc = true;
+			stripe->alloc = true;
 		}
 
-		sp2d->_1p_stripes[i].pages = __a1pa->pages;
-		sp2d->_1p_stripes[i].scribble = __a1pa->scribble ;
-		sp2d->_1p_stripes[i].page_is_read = __a1pa->page_is_read;
-		++__a1pa;
+		/*
+		 * Attach all _lp_stripes pointers to the allocation for
+		 * it which was either part of the original PAGE_SIZE
+		 * allocation or the subsequent allocation in this loop.
+		 */
+		stripe->pages = (void *)__a1pa;
+		stripe->scribble = stripe->pages + group_width;
+		stripe->page_is_read = (char *)stripe->scribble + group_width;
+		__a1pa += sizeof__a1pa;
 	}
 
 	sp2d->parity = parity;

fs/exofs/super.c

···
 static int __alloc_dev_table(struct exofs_sb_info *sbi, unsigned numdevs,
 		      struct exofs_dev **peds)
 {
-	struct __alloc_ore_devs_and_exofs_devs {
-		/* Twice bigger table: See exofs_init_comps() and comment at
-		 * exofs_read_lookup_dev_table()
-		 */
-		struct ore_dev *oreds[numdevs * 2 - 1];
-		struct exofs_dev eds[numdevs];
-	} *aoded;
+	/* Twice bigger table: See exofs_init_comps() and comment at
+	 * exofs_read_lookup_dev_table()
+	 */
+	const size_t numores = numdevs * 2 - 1;
 	struct exofs_dev *eds;
 	unsigned i;
 
-	aoded = kzalloc(sizeof(*aoded), GFP_KERNEL);
-	if (unlikely(!aoded)) {
+	sbi->oc.ods = kzalloc(numores * sizeof(struct ore_dev *) +
+			      numdevs * sizeof(struct exofs_dev), GFP_KERNEL);
+	if (unlikely(!sbi->oc.ods)) {
 		EXOFS_ERR("ERROR: failed allocating Device array[%d]\n",
 			  numdevs);
 		return -ENOMEM;
 	}
 
-	sbi->oc.ods = aoded->oreds;
-	*peds = eds = aoded->eds;
+	/* Start of allocated struct exofs_dev entries */
+	*peds = eds = (void *)sbi->oc.ods[numores];
+	/* Initialize pointers into struct exofs_dev */
 	for (i = 0; i < numdevs; ++i)
-		aoded->oreds[i] = &eds[i].ored;
+		sbi->oc.ods[i] = &eds[i].ored;
 	return 0;
 }
 

fs/fat/inode.c

···
 	err = fat_bmap(inode, iblock, &phys, &mapped_blocks, create, false);
 	if (err)
 		return err;
+	if (!phys) {
+		fat_fs_error(sb,
+			     "invalid FAT chain (i_pos %lld, last_block %llu)",
+			     MSDOS_I(inode)->i_pos,
+			     (unsigned long long)last_block);
+		return -EIO;
+	}
 
-	BUG_ON(!phys);
 	BUG_ON(*max_blocks != mapped_blocks);
 	set_buffer_new(bh_result);
 	map_bh(bh_result, sb, phys);

fs/proc/base.c

···
 	for (p = ents; p < last; p++) {
 		if (p->len != dentry->d_name.len)
 			continue;
-		if (!memcmp(dentry->d_name.name, p->name, p->len))
+		if (!memcmp(dentry->d_name.name, p->name, p->len)) {
+			res = proc_pident_instantiate(dentry, task, p);
 			break;
+		}
 	}
-	if (p >= last)
-		goto out;
-
-	res = proc_pident_instantiate(dentry, task, p);
-out:
 	put_task_struct(task);
 out_no_task:
 	return res;

include/linux/kcov.h

···
 	KCOV_MODE_TRACE_CMP = 3,
 };
 
+#define KCOV_IN_CTXSW	(1 << 30)
+
 void kcov_task_init(struct task_struct *t);
 void kcov_task_exit(struct task_struct *t);
+
+#define kcov_prepare_switch(t)			\
+do {						\
+	(t)->kcov_mode |= KCOV_IN_CTXSW;	\
+} while (0)
+
+#define kcov_finish_switch(t)			\
+do {						\
+	(t)->kcov_mode &= ~KCOV_IN_CTXSW;	\
+} while (0)
 
 #else
 
 static inline void kcov_task_init(struct task_struct *t) {}
 static inline void kcov_task_exit(struct task_struct *t) {}
+static inline void kcov_prepare_switch(struct task_struct *t) {}
+static inline void kcov_finish_switch(struct task_struct *t) {}
 
 #endif /* CONFIG_KCOV */
 #endif /* _LINUX_KCOV_H */

include/linux/memcontrol.h

···
 	MEMCG_HIGH,
 	MEMCG_MAX,
 	MEMCG_OOM,
+	MEMCG_OOM_KILL,
 	MEMCG_SWAP_MAX,
 	MEMCG_SWAP_FAIL,
 	MEMCG_NR_MEMORY_EVENTS,
···
 
 	rcu_read_lock();
 	memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
-	if (likely(memcg)) {
+	if (likely(memcg))
 		count_memcg_events(memcg, idx, 1);
-		if (idx == OOM_KILL)
-			cgroup_file_notify(&memcg->events_file);
-	}
 	rcu_read_unlock();
 }
 
···
 {
 	atomic_long_inc(&memcg->memory_events[event]);
 	cgroup_file_notify(&memcg->events_file);
+}
+
+static inline void memcg_memory_event_mm(struct mm_struct *mm,
+					 enum memcg_memory_event event)
+{
+	struct mem_cgroup *memcg;
+
+	if (mem_cgroup_disabled())
+		return;
+
+	rcu_read_lock();
+	memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
+	if (likely(memcg))
+		memcg_memory_event(memcg, event);
+	rcu_read_unlock();
 }
 
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
···
 
 static inline void memcg_memory_event(struct mem_cgroup *memcg,
 				      enum memcg_memory_event event)
+{
+}
+
+static inline void memcg_memory_event_mm(struct mm_struct *mm,
+					 enum memcg_memory_event event)
 {
 }
 

include/linux/sched.h

···
 
 #ifdef CONFIG_KCOV
 	/* Coverage collection mode enabled for this task (0 if disabled): */
-	enum kcov_mode			kcov_mode;
+	unsigned int			kcov_mode;
 
 	/* Size of the kcov_area: */
 	unsigned int			kcov_size;

include/linux/slab.h

···
 			struct memcg_cache_array __rcu *memcg_caches;
 			struct list_head __root_caches_node;
 			struct list_head children;
+			bool dying;
 		};
 		struct {
 			struct mem_cgroup *memcg;

ipc/sem.c

···
 #include <linux/nsproxy.h>
 #include <linux/ipc_namespace.h>
 #include <linux/sched/wake_q.h>
+#include <linux/nospec.h>
 
 #include <linux/uaccess.h>
 #include "util.h"
···
 			      int nsops)
 {
 	struct sem *sem;
+	int idx;
 
 	if (nsops != 1) {
 		/* Complex operation - acquire a full lock */
···
 	 *
 	 * Both facts are tracked by use_global_mode.
 	 */
-	sem = &sma->sems[sops->sem_num];
+	idx = array_index_nospec(sops->sem_num, sma->sem_nsems);
+	sem = &sma->sems[idx];
 
 	/*
 	 * Initial check for use_global_lock. Just an optimization,
···
 	un = q->undo;
 
 	for (sop = sops; sop < sops + nsops; sop++) {
-		curr = &sma->sems[sop->sem_num];
+		int idx = array_index_nospec(sop->sem_num, sma->sem_nsems);
+		curr = &sma->sems[idx];
 		sem_op = sop->sem_op;
 		result = curr->semval;
 
···
 	 * until the operations can go through.
 	 */
 	for (sop = sops; sop < sops + nsops; sop++) {
-		curr = &sma->sems[sop->sem_num];
+		int idx = array_index_nospec(sop->sem_num, sma->sem_nsems);
+
+		curr = &sma->sems[idx];
 		sem_op = sop->sem_op;
 		result = curr->semval;
 
···
 		return -EIDRM;
 	}
 
+	semnum = array_index_nospec(semnum, sma->sem_nsems);
 	curr = &sma->sems[semnum];
 
 	ipc_assert_locked_object(&sma->sem_perm);
···
 		err = -EIDRM;
 		goto out_unlock;
 	}
+
+	semnum = array_index_nospec(semnum, nsems);
 	curr = &sma->sems[semnum];
 
 	switch (cmd) {
···
 	 */
 	if (nsops == 1) {
 		struct sem *curr;
-		curr = &sma->sems[sops->sem_num];
+		int idx = array_index_nospec(sops->sem_num, sma->sem_nsems);
+		curr = &sma->sems[idx];
 
 		if (alter) {
 			if (sma->complex_count) {

ipc/shm.c

···
 	up_write(&shm_ids(ns).rwsem);
 }
 
-static int shm_fault(struct vm_fault *vmf)
+static vm_fault_t shm_fault(struct vm_fault *vmf)
 {
 	struct file *file = vmf->vma->vm_file;
 	struct shm_file_data *sfd = shm_file_data(file);

kernel/fork.c

···
 			continue;
 		}
 		charge = 0;
+		/*
+		 * Don't duplicate many vmas if we've been oom-killed (for
+		 * example)
+		 */
+		if (fatal_signal_pending(current)) {
+			retval = -EINTR;
+			goto out;
+		}
 		if (mpnt->vm_flags & VM_ACCOUNT) {
 			unsigned long len = vma_pages(mpnt);
 

kernel/kcov.c

···
 
 static bool check_kcov_mode(enum kcov_mode needed_mode, struct task_struct *t)
 {
-	enum kcov_mode mode;
+	unsigned int mode;
 
 	/*
 	 * We are interested in code coverage as a function of a syscall inputs,
···
 
 void kcov_task_init(struct task_struct *t)
 {
-	t->kcov_mode = KCOV_MODE_DISABLED;
+	WRITE_ONCE(t->kcov_mode, KCOV_MODE_DISABLED);
+	barrier();
 	t->kcov_size = 0;
 	t->kcov_area = NULL;
 	t->kcov = NULL;
···
 	return 0;
 }
 
+/*
+ * Fault in a lazily-faulted vmalloc area before it can be used by
+ * __santizer_cov_trace_pc(), to avoid recursion issues if any code on the
+ * vmalloc fault handling path is instrumented.
+ */
+static void kcov_fault_in_area(struct kcov *kcov)
+{
+	unsigned long stride = PAGE_SIZE / sizeof(unsigned long);
+	unsigned long *area = kcov->area;
+	unsigned long offset;
+
+	for (offset = 0; offset < kcov->size; offset += stride)
+		READ_ONCE(area[offset]);
+}
+
 static int kcov_ioctl_locked(struct kcov *kcov, unsigned int cmd,
 			     unsigned long arg)
 {
···
 #endif
 		else
 			return -EINVAL;
+		kcov_fault_in_area(kcov);
 		/* Cache in task struct for performance. */
 		t->kcov_size = kcov->size;
 		t->kcov_area = kcov->area;

kernel/kexec_core.c

···
 		else
 			buf += mchunk;
 		mbytes -= mchunk;
+
+		cond_resched();
 	}
 out:
 	return result;
···
 		else
 			buf += mchunk;
 		mbytes -= mchunk;
+
+		cond_resched();
 	}
 out:
 	return result;

kernel/relay.c

···
 /*
  * fault() vm_op implementation for relay file mapping.
  */
-static int relay_buf_fault(struct vm_fault *vmf)
+static vm_fault_t relay_buf_fault(struct vm_fault *vmf)
 {
 	struct page *page;
 	struct rchan_buf *buf = vmf->vma->vm_private_data;

kernel/sched/core.c

···
 #include <linux/kthread.h>
 #include <linux/nospec.h>
 
+#include <linux/kcov.h>
+
 #include <asm/switch_to.h>
 #include <asm/tlb.h>
 
···
 prepare_task_switch(struct rq *rq, struct task_struct *prev,
 		    struct task_struct *next)
 {
+	kcov_prepare_switch(prev);
 	sched_info_switch(rq, prev, next);
 	perf_event_task_sched_out(prev, next);
 	rseq_preempt(prev);
···
 	finish_task(prev);
 	finish_lock_switch(rq);
 	finish_arch_post_lock_switch();
+	kcov_finish_switch(current);
 
 	fire_sched_in_preempt_notifiers(current);
 	/*

lib/Kconfig.debug

···
 
 	  If unsure, say N.
 
+config FUNCTION_ERROR_INJECTION
+	def_bool y
+	depends on HAVE_FUNCTION_ERROR_INJECTION && KPROBES
+
 config FAULT_INJECTION
 	bool "Fault-injection framework"
 	depends on DEBUG_KERNEL
 	help
 	  Provide fault-injection framework.
 	  For more details, see Documentation/fault-injection/.
-
-config FUNCTION_ERROR_INJECTION
-	def_bool y
-	depends on HAVE_FUNCTION_ERROR_INJECTION && KPROBES
 
 config FAILSLAB
 	bool "Fault-injection capability for kmalloc"
···
 	  Only works with drivers that use the generic timeout handling,
 	  for others it wont do anything.
 
-config FAIL_MMC_REQUEST
-	bool "Fault-injection capability for MMC IO"
-	depends on FAULT_INJECTION_DEBUG_FS && MMC
-	help
-	  Provide fault-injection capability for MMC IO.
-	  This will make the mmc core return data errors. This is
-	  useful to test the error handling in the mmc block device
-	  and to test how the mmc host driver handles retries from
-	  the block device.
-
 config FAIL_FUTEX
 	bool "Fault-injection capability for futexes"
 	select DEBUG_FS
 	depends on FAULT_INJECTION && FUTEX
 	help
 	  Provide fault-injection capability for futexes.
+
+config FAULT_INJECTION_DEBUG_FS
+	bool "Debugfs entries for fault-injection capabilities"
+	depends on FAULT_INJECTION && SYSFS && DEBUG_FS
+	help
+	  Enable configuration of fault-injection capabilities via debugfs.
 
 config FAIL_FUNCTION
 	bool "Fault-injection capability for functions"
···
 	  an error value and have to handle it. This is useful to test the
 	  error handling in various subsystems.
 
-config FAULT_INJECTION_DEBUG_FS
-	bool "Debugfs entries for fault-injection capabilities"
-	depends on FAULT_INJECTION && SYSFS && DEBUG_FS
+config FAIL_MMC_REQUEST
+	bool "Fault-injection capability for MMC IO"
+	depends on FAULT_INJECTION_DEBUG_FS && MMC
 	help
-	  Enable configuration of fault-injection capabilities via debugfs.
+	  Provide fault-injection capability for MMC IO.
+	  This will make the mmc core return data errors. This is
+	  useful to test the error handling in the mmc block device
+	  and to test how the mmc host driver handles retries from
+	  the block device.
 
 config FAULT_INJECTION_STACKTRACE_FILTER
 	bool "stacktrace filter for fault-injection capabilities"

lib/test_printf.c

···
 {
 	int err;
 
+	/*
+	 * Make sure crng is ready. Otherwise we get "(ptrval)" instead
+	 * of a hashed address when printing '%p' in plain_hash() and
+	 * plain_format().
+	 */
+	wait_for_random_bytes();
+
 	err = plain_hash();
 	if (err) {
 		pr_warn("plain 'p' does not appear to be hashed\n");

mm/cleancache.c

···
 	struct dentry *root = debugfs_create_dir("cleancache", NULL);
 	if (root == NULL)
 		return -ENXIO;
-	debugfs_create_u64("succ_gets", S_IRUGO, root, &cleancache_succ_gets);
-	debugfs_create_u64("failed_gets", S_IRUGO,
-				root, &cleancache_failed_gets);
-	debugfs_create_u64("puts", S_IRUGO, root, &cleancache_puts);
-	debugfs_create_u64("invalidates", S_IRUGO,
-				root, &cleancache_invalidates);
+	debugfs_create_u64("succ_gets", 0444, root, &cleancache_succ_gets);
+	debugfs_create_u64("failed_gets", 0444, root, &cleancache_failed_gets);
+	debugfs_create_u64("puts", 0444, root, &cleancache_puts);
+	debugfs_create_u64("invalidates", 0444, root, &cleancache_invalidates);
 #endif
 	return 0;
 }

mm/cma_debug.c

···
 
 	tmp = debugfs_create_dir(name, cma_debugfs_root);
 
-	debugfs_create_file("alloc", S_IWUSR, tmp, cma,
-				&cma_alloc_fops);
-
-	debugfs_create_file("free", S_IWUSR, tmp, cma,
-				&cma_free_fops);
-
-	debugfs_create_file("base_pfn", S_IRUGO, tmp,
-				&cma->base_pfn, &cma_debugfs_fops);
-	debugfs_create_file("count", S_IRUGO, tmp,
-				&cma->count, &cma_debugfs_fops);
-	debugfs_create_file("order_per_bit", S_IRUGO, tmp,
-				&cma->order_per_bit, &cma_debugfs_fops);
-	debugfs_create_file("used", S_IRUGO, tmp, cma, &cma_used_fops);
-	debugfs_create_file("maxchunk", S_IRUGO, tmp, cma, &cma_maxchunk_fops);
+	debugfs_create_file("alloc", 0200, tmp, cma, &cma_alloc_fops);
+	debugfs_create_file("free", 0200, tmp, cma, &cma_free_fops);
+	debugfs_create_file("base_pfn", 0444, tmp,
+			    &cma->base_pfn, &cma_debugfs_fops);
+	debugfs_create_file("count", 0444, tmp, &cma->count, &cma_debugfs_fops);
+	debugfs_create_file("order_per_bit", 0444, tmp,
+			    &cma->order_per_bit, &cma_debugfs_fops);
+	debugfs_create_file("used", 0444, tmp, cma, &cma_used_fops);
+	debugfs_create_file("maxchunk", 0444, tmp, cma, &cma_maxchunk_fops);
 
 	u32s = DIV_ROUND_UP(cma_bitmap_maxno(cma), BITS_PER_BYTE * sizeof(u32));
-	debugfs_create_u32_array("bitmap", S_IRUGO, tmp, (u32*)cma->bitmap, u32s);
+	debugfs_create_u32_array("bitmap", 0444, tmp, (u32 *)cma->bitmap, u32s);
 }
 
 static int __init cma_debugfs_init(void)

mm/compaction.c

···
 
 	return count;
 }
-static DEVICE_ATTR(compact, S_IWUSR, NULL, sysfs_compact_node);
+static DEVICE_ATTR(compact, 0200, NULL, sysfs_compact_node);
 
 int compaction_register_node(struct node *node)
 {

mm/dmapool.c

···
 	return PAGE_SIZE - size;
 }
 
-static DEVICE_ATTR(pools, S_IRUGO, show_pools, NULL);
+static DEVICE_ATTR(pools, 0444, show_pools, NULL);
 
 /**
  * dma_pool_create - Creates a pool of consistent memory blocks, for dma.

mm/failslab.c

···
 static int __init failslab_debugfs_init(void)
 {
 	struct dentry *dir;
-	umode_t mode = S_IFREG | S_IRUSR | S_IWUSR;
+	umode_t mode = S_IFREG | 0600;
 
 	dir = fault_create_debugfs_attr("failslab", NULL, &failslab.attr);
 	if (IS_ERR(dir))

mm/frontswap.c

···
 	struct dentry *root = debugfs_create_dir("frontswap", NULL);
 	if (root == NULL)
 		return -ENXIO;
-	debugfs_create_u64("loads", S_IRUGO, root, &frontswap_loads);
-	debugfs_create_u64("succ_stores", S_IRUGO, root, &frontswap_succ_stores);
-	debugfs_create_u64("failed_stores", S_IRUGO, root,
-				&frontswap_failed_stores);
-	debugfs_create_u64("invalidates", S_IRUGO,
-				root, &frontswap_invalidates);
+	debugfs_create_u64("loads", 0444, root, &frontswap_loads);
+	debugfs_create_u64("succ_stores", 0444, root, &frontswap_succ_stores);
+	debugfs_create_u64("failed_stores", 0444, root,
+			   &frontswap_failed_stores);
+	debugfs_create_u64("invalidates", 0444, root, &frontswap_invalidates);
 #endif
 	return 0;
 }

mm/ksm.c

···
 #define SEQNR_MASK	0x0ff	/* low bits of unstable tree seqnr */
 #define UNSTABLE_FLAG	0x100	/* is a node of the unstable tree */
 #define STABLE_FLAG	0x200	/* is listed from the stable tree */
+#define KSM_FLAG_MASK	(SEQNR_MASK|UNSTABLE_FLAG|STABLE_FLAG)
+				/* to mask all the flags */
 
 /* The stable and unstable tree heads */
 static struct rb_root one_stable_tree[1] = { RB_ROOT };
···
 		anon_vma_lock_read(anon_vma);
 		anon_vma_interval_tree_foreach(vmac, &anon_vma->rb_root,
 					       0, ULONG_MAX) {
+			unsigned long addr;
+
 			cond_resched();
 			vma = vmac->vma;
-			if (rmap_item->address < vma->vm_start ||
-			    rmap_item->address >= vma->vm_end)
+
+			/* Ignore the stable/unstable/sqnr flags */
+			addr = rmap_item->address & ~KSM_FLAG_MASK;
+
+			if (addr < vma->vm_start || addr >= vma->vm_end)
 				continue;
 			/*
 			 * Initially we examine only the vma which covers this
···
 			if (rwc->invalid_vma && rwc->invalid_vma(vma, rwc->arg))
 				continue;
 
-			if (!rwc->rmap_one(page, vma,
-					rmap_item->address, rwc->arg)) {
+			if (!rwc->rmap_one(page, vma, addr, rwc->arg)) {
 				anon_vma_unlock_read(anon_vma);
 				return;
 			}

mm/memblock.c

···
 #include <linux/kmemleak.h>
 #include <linux/seq_file.h>
 #include <linux/memblock.h>
+#include <linux/bootmem.h>
 
 #include <asm/sections.h>
 #include <linux/io.h>
···
 	struct dentry *root = debugfs_create_dir("memblock", NULL);
 	if (!root)
 		return -ENXIO;
-	debugfs_create_file("memory", S_IRUGO, root, &memblock.memory, &memblock_debug_fops);
-	debugfs_create_file("reserved", S_IRUGO, root, &memblock.reserved, &memblock_debug_fops);
+	debugfs_create_file("memory", 0444, root,
+			    &memblock.memory, &memblock_debug_fops);
+	debugfs_create_file("reserved", 0444, root,
+			    &memblock.reserved, &memblock_debug_fops);
 #ifdef CONFIG_HAVE_MEMBLOCK_PHYS_MAP
-	debugfs_create_file("physmem", S_IRUGO, root, &memblock.physmem, &memblock_debug_fops);
+	debugfs_create_file("physmem", 0444, root,
+			    &memblock.physmem, &memblock_debug_fops);
 #endif
 
 	return 0;

mm/memcontrol.c

···
 
 	seq_printf(sf, "oom_kill_disable %d\n", memcg->oom_kill_disable);
 	seq_printf(sf, "under_oom %d\n", (bool)memcg->under_oom);
-	seq_printf(sf, "oom_kill %lu\n", memcg_sum_events(memcg, OOM_KILL));
+	seq_printf(sf, "oom_kill %lu\n",
+		   atomic_long_read(&memcg->memory_events[MEMCG_OOM_KILL]));
 	return 0;
 }
 
···
 		   atomic_long_read(&memcg->memory_events[MEMCG_MAX]));
 	seq_printf(m, "oom %lu\n",
 		   atomic_long_read(&memcg->memory_events[MEMCG_OOM]));
-	seq_printf(m, "oom_kill %lu\n", memcg_sum_events(memcg, OOM_KILL));
+	seq_printf(m, "oom_kill %lu\n",
+		   atomic_long_read(&memcg->memory_events[MEMCG_OOM_KILL]));
 
 	return 0;
 }
···
 	elow = memcg->memory.low;
 
 	parent = parent_mem_cgroup(memcg);
+	/* No parent means a non-hierarchical mode on v1 memcg */
+	if (!parent)
+		return MEMCG_PROT_NONE;
+
 	if (parent == root)
 		goto exit;
 

mm/mremap.c

···
 		drop_rmap_locks(vma);
 }
 
-#define LATENCY_LIMIT	(64 * PAGE_SIZE)
-
 unsigned long move_page_tables(struct vm_area_struct *vma,
 		unsigned long old_addr, struct vm_area_struct *new_vma,
 		unsigned long new_addr, unsigned long len,
···
 		next = (new_addr + PMD_SIZE) & PMD_MASK;
 		if (extent > next - new_addr)
 			extent = next - new_addr;
-		if (extent > LATENCY_LIMIT)
-			extent = LATENCY_LIMIT;
 		move_ptes(vma, old_pmd, old_addr, old_addr + extent, new_vma,
 			  new_pmd, new_addr, need_rmap_locks, &need_flush);
 	}

mm/oom_kill.c

···
 
 	/* Raise event before sending signal: task reaper must see this */
 	count_vm_event(OOM_KILL);
-	count_memcg_event_mm(mm, OOM_KILL);
+	memcg_memory_event_mm(mm, MEMCG_OOM_KILL);
 
 	/*
 	 * We should send SIGKILL before granting access to memory reserves

mm/page_alloc.c

···
 
 static int __init fail_page_alloc_debugfs(void)
 {
-	umode_t mode = S_IFREG | S_IRUSR | S_IWUSR;
+	umode_t mode = S_IFREG | 0600;
 	struct dentry *dir;
 
 	dir = fault_create_debugfs_attr("fail_page_alloc", NULL,

mm/page_idle.c

···
 }
 
 static struct bin_attribute page_idle_bitmap_attr =
-		__BIN_ATTR(bitmap, S_IRUSR | S_IWUSR,
+		__BIN_ATTR(bitmap, 0600,
 			   page_idle_bitmap_read, page_idle_bitmap_write, 0);
 
 static struct bin_attribute *page_idle_bin_attrs[] = {

mm/page_owner.c

···
 		return 0;
 	}
 
-	dentry = debugfs_create_file("page_owner", S_IRUSR, NULL,
-			NULL, &proc_page_owner_operations);
+	dentry = debugfs_create_file("page_owner", 0400, NULL,
+				     NULL, &proc_page_owner_operations);
 
 	return PTR_ERR_OR_ZERO(dentry);
 }

mm/shmem.c

···
 	if (len > PAGE_SIZE)
 		return -ENAMETOOLONG;
 
-	inode = shmem_get_inode(dir->i_sb, dir, S_IFLNK|S_IRWXUGO, 0, VM_NORESERVE);
+	inode = shmem_get_inode(dir->i_sb, dir, S_IFLNK | 0777, 0,
+				VM_NORESERVE);
 	if (!inode)
 		return -ENOSPC;
 
···
 			sbinfo->max_blocks << (PAGE_SHIFT - 10));
 	if (sbinfo->max_inodes != shmem_default_max_inodes())
 		seq_printf(seq, ",nr_inodes=%lu", sbinfo->max_inodes);
-	if (sbinfo->mode != (S_IRWXUGO | S_ISVTX))
+	if (sbinfo->mode != (0777 | S_ISVTX))
 		seq_printf(seq, ",mode=%03ho", sbinfo->mode);
 	if (!uid_eq(sbinfo->uid, GLOBAL_ROOT_UID))
 		seq_printf(seq, ",uid=%u",
···
 	if (!sbinfo)
 		return -ENOMEM;
 
-	sbinfo->mode = S_IRWXUGO | S_ISVTX;
+	sbinfo->mode = 0777 | S_ISVTX;
 	sbinfo->uid = current_fsuid();
 	sbinfo->gid = current_fsgid();
 	sb->s_fs_info = sbinfo;
···
 	d_set_d_op(path.dentry, &anon_ops);
 
 	res = ERR_PTR(-ENOSPC);
-	inode = shmem_get_inode(sb, NULL, S_IFREG | S_IRWXUGO, 0, flags);
+	inode = shmem_get_inode(sb, NULL, S_IFREG | 0777, 0, flags);
 	if (!inode)
 		goto put_memory;
 

mm/slab_common.c

···
 	s->memcg_params.root_cache = NULL;
 	RCU_INIT_POINTER(s->memcg_params.memcg_caches, NULL);
 	INIT_LIST_HEAD(&s->memcg_params.children);
+	s->memcg_params.dying = false;
 }
 
 static int init_memcg_params(struct kmem_cache *s,
···
 	 * The memory cgroup could have been offlined while the cache
 	 * creation work was pending.
 	 */
-	if (memcg->kmem_state != KMEM_ONLINE)
+	if (memcg->kmem_state != KMEM_ONLINE || root_cache->memcg_params.dying)
 		goto out_unlock;
 
 	idx = memcg_cache_id(memcg);
···
 {
 	if (WARN_ON_ONCE(is_root_cache(s)) ||
 	    WARN_ON_ONCE(s->memcg_params.deact_fn))
+		return;
+
+	if (s->memcg_params.root_cache->memcg_params.dying)
 		return;
 
 	/* pin memcg so that @s doesn't get destroyed in the middle */
···
 		return -EBUSY;
 	return 0;
 }
+
+static void flush_memcg_workqueue(struct kmem_cache *s)
+{
+	mutex_lock(&slab_mutex);
+	s->memcg_params.dying = true;
+	mutex_unlock(&slab_mutex);
+
+	/*
+	 * SLUB deactivates the kmem_caches through call_rcu_sched. Make
+	 * sure all registered rcu callbacks have been invoked.
+	 */
+	if (IS_ENABLED(CONFIG_SLUB))
+		rcu_barrier_sched();
+
+	/*
+	 * SLAB and SLUB create memcg kmem_caches through workqueue and SLUB
+	 * deactivates the memcg kmem_caches through workqueue. Make sure all
+	 * previous workitems on workqueue are processed.
+	 */
+	flush_workqueue(memcg_kmem_cache_wq);
+}
 #else
 static inline int shutdown_memcg_caches(struct kmem_cache *s)
 {
 	return 0;
+}
+
+static inline void flush_memcg_workqueue(struct kmem_cache *s)
+{
 }
 #endif /* CONFIG_MEMCG && !CONFIG_SLOB */
 
···
 
 	if (unlikely(!s))
 		return;
+
+	flush_memcg_workqueue(s);
 
 	get_online_cpus();
 	get_online_mems();
···
 
 #if defined(CONFIG_SLAB) || defined(CONFIG_SLUB_DEBUG)
 #ifdef CONFIG_SLAB
-#define SLABINFO_RIGHTS (S_IWUSR | S_IRUSR)
+#define SLABINFO_RIGHTS (0600)
 #else
-#define SLABINFO_RIGHTS S_IRUSR
+#define SLABINFO_RIGHTS (0400)
 #endif
 
 static void print_slabinfo_header(struct seq_file *m)

mm/swapfile.c

···
 
 static inline unsigned char swap_count(unsigned char ent)
 {
-	return ent & ~SWAP_HAS_CACHE;	/* may include SWAP_HAS_CONT flag */
+	return ent & ~SWAP_HAS_CACHE;	/* may include COUNT_CONTINUED flag */
 }
 
 /* returns 1 if swap entry is freed */

mm/vmalloc.c

···
 static int __init proc_vmalloc_init(void)
 {
 	if (IS_ENABLED(CONFIG_NUMA))
-		proc_create_seq_private("vmallocinfo", S_IRUSR, NULL,
+		proc_create_seq_private("vmallocinfo", 0400, NULL,
 				&vmalloc_op,
 				nr_node_ids * sizeof(unsigned int), NULL);
 	else
-		proc_create_seq("vmallocinfo", S_IRUSR, NULL, &vmalloc_op);
+		proc_create_seq("vmallocinfo", 0400, NULL, &vmalloc_op);
 	return 0;
 }
 module_init(proc_vmalloc_init);

mm/zsmalloc.c

···
 	}
 	pool->stat_dentry = entry;
 
-	entry = debugfs_create_file("classes", S_IFREG | S_IRUGO,
-			pool->stat_dentry, pool, &zs_stats_size_fops);
+	entry = debugfs_create_file("classes", S_IFREG | 0444,
+				    pool->stat_dentry, pool,
+				    &zs_stats_size_fops);
 	if (!entry) {
 		pr_warn("%s: debugfs file entry <%s> creation failed\n",
 				name, "classes");

mm/zswap.c

···
 	if (!zswap_debugfs_root)
 		return -ENOMEM;
 
-	debugfs_create_u64("pool_limit_hit", S_IRUGO,
-			zswap_debugfs_root, &zswap_pool_limit_hit);
-	debugfs_create_u64("reject_reclaim_fail", S_IRUGO,
-			zswap_debugfs_root, &zswap_reject_reclaim_fail);
-	debugfs_create_u64("reject_alloc_fail", S_IRUGO,
-			zswap_debugfs_root, &zswap_reject_alloc_fail);
-	debugfs_create_u64("reject_kmemcache_fail", S_IRUGO,
-			zswap_debugfs_root, &zswap_reject_kmemcache_fail);
-	debugfs_create_u64("reject_compress_poor", S_IRUGO,
-			zswap_debugfs_root, &zswap_reject_compress_poor);
-	debugfs_create_u64("written_back_pages", S_IRUGO,
-			zswap_debugfs_root, &zswap_written_back_pages);
-	debugfs_create_u64("duplicate_entry", S_IRUGO,
-			zswap_debugfs_root, &zswap_duplicate_entry);
-	debugfs_create_u64("pool_total_size", S_IRUGO,
-			zswap_debugfs_root, &zswap_pool_total_size);
-	debugfs_create_atomic_t("stored_pages", S_IRUGO,
-			zswap_debugfs_root, &zswap_stored_pages);
+	debugfs_create_u64("pool_limit_hit", 0444,
+			   zswap_debugfs_root, &zswap_pool_limit_hit);
+	debugfs_create_u64("reject_reclaim_fail", 0444,
+			   zswap_debugfs_root, &zswap_reject_reclaim_fail);
+	debugfs_create_u64("reject_alloc_fail", 0444,
+			   zswap_debugfs_root, &zswap_reject_alloc_fail);
+	debugfs_create_u64("reject_kmemcache_fail", 0444,
+			   zswap_debugfs_root, &zswap_reject_kmemcache_fail);
+	debugfs_create_u64("reject_compress_poor", 0444,
+			   zswap_debugfs_root, &zswap_reject_compress_poor);
+	debugfs_create_u64("written_back_pages", 0444,
+			   zswap_debugfs_root, &zswap_written_back_pages);
+	debugfs_create_u64("duplicate_entry", 0444,
+			   zswap_debugfs_root, &zswap_duplicate_entry);
+	debugfs_create_u64("pool_total_size", 0444,
+			   zswap_debugfs_root, &zswap_pool_total_size);
+	debugfs_create_atomic_t("stored_pages", 0444,
+				zswap_debugfs_root, &zswap_stored_pages);
 	debugfs_create_atomic_t("same_filled_pages", 0444,
-			zswap_debugfs_root, &zswap_same_filled_pages);
+				zswap_debugfs_root, &zswap_same_filled_pages);
 
 	return 0;
 }