Merge tag 'mm-hotfixes-stable-2023-11-17-14-04' of git://git.kernel.o…

…rg/pub/scm/linux/kernel/git/akpm/mm

Pull misc fixes from Andrew Morton:
 "Thirteen hotfixes. Seven are cc:stable and the remainder pertain to
  post-6.6 issues or aren't considered suitable for backporting"

* tag 'mm-hotfixes-stable-2023-11-17-14-04' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  mm: more ptep_get() conversion
  parisc: fix mmap_base calculation when stack grows upwards
  mm/damon/core.c: avoid unintentional filtering out of schemes
  mm: kmem: drop __GFP_NOFAIL when allocating objcg vectors
  mm/damon/sysfs-schemes: handle tried region directory allocation failure
  mm/damon/sysfs-schemes: handle tried regions sysfs directory allocation failure
  mm/damon/sysfs: check error from damon_sysfs_update_target()
  mm: fix for negative counter: nr_file_hugepages
  selftests/mm: add hugetlb_fault_after_madv to .gitignore
  selftests/mm: restore number of hugepages
  selftests: mm: fix some build warnings
  selftests: mm: skip whole test instead of failure
  mm/damon/sysfs: eliminate potential uninitialized variable warning

arch/parisc/Kconfig

@@ -140,11 +140,11 @@ config ARCH_MMAP_RND_COMPAT_BITS_MIN
 	default 8
 
 config ARCH_MMAP_RND_BITS_MAX
-	default 24 if 64BIT
-	default 17
+	default 18 if 64BIT
+	default 13
 
 config ARCH_MMAP_RND_COMPAT_BITS_MAX
-	default 17
+	default 13
 
 # unless you want to implement ACPI on PA-RISC ... ;-)
 config PM

arch/parisc/include/asm/elf.h

@@ -349,15 +349,7 @@ struct pt_regs;	/* forward declaration... */
 
 #define ELF_HWCAP	0
 
-/* Masks for stack and mmap randomization */
-#define BRK_RND_MASK	(is_32bit_task() ? 0x07ffUL : 0x3ffffUL)
-#define MMAP_RND_MASK	(is_32bit_task() ? 0x1fffUL : 0x3ffffUL)
-#define STACK_RND_MASK	MMAP_RND_MASK
-
-struct mm_struct;
-extern unsigned long arch_randomize_brk(struct mm_struct *);
-#define arch_randomize_brk arch_randomize_brk
-
+#define STACK_RND_MASK	0x7ff	/* 8MB of VA */
 
 #define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1
 struct linux_binprm;

arch/parisc/include/asm/processor.h

@@ -47,6 +47,8 @@
 
 #ifndef __ASSEMBLY__
 
+struct rlimit;
+unsigned long mmap_upper_limit(struct rlimit *rlim_stack);
 unsigned long calc_max_stack_size(unsigned long stack_max);
 
 /*

arch/parisc/kernel/sys_parisc.c

@@ -77,7 +77,7 @@ unsigned long calc_max_stack_size(unsigned long stack_max)
  * indicating that "current" should be used instead of a passed-in
  * value from the exec bprm as done with arch_pick_mmap_layout().
  */
-static unsigned long mmap_upper_limit(struct rlimit *rlim_stack)
+unsigned long mmap_upper_limit(struct rlimit *rlim_stack)
 {
 	unsigned long stack_base;
 

mm/damon/core.c

@@ -924,7 +924,7 @@ static bool __damos_filter_out(struct damon_ctx *ctx, struct damon_target *t,
 		matched = true;
 		break;
 	default:
-		break;
+		return false;
 	}
 
 	return matched == filter->matching;

mm/damon/sysfs-schemes.c

@@ -162,6 +162,9 @@ damon_sysfs_scheme_regions_alloc(void)
 	struct damon_sysfs_scheme_regions *regions = kmalloc(sizeof(*regions),
 			GFP_KERNEL);
 
+	if (!regions)
+		return NULL;
+
 	regions->kobj = (struct kobject){};
 	INIT_LIST_HEAD(&regions->regions_list);
 	regions->nr_regions = 0;
@@ -1823,6 +1826,8 @@ static int damon_sysfs_before_damos_apply(struct damon_ctx *ctx,
 		return 0;
 
 	region = damon_sysfs_scheme_region_alloc(r);
+	if (!region)
+		return 0;
 	list_add_tail(&region->list, &sysfs_regions->regions_list);
 	sysfs_regions->nr_regions++;
 	if (kobject_init_and_add(&region->kobj,

mm/damon/sysfs.c

@@ -1172,7 +1172,7 @@ static int damon_sysfs_update_target(struct damon_target *target,
 		struct damon_ctx *ctx,
 		struct damon_sysfs_target *sys_target)
 {
-	int err;
+	int err = 0;
 
 	if (damon_target_has_pid(ctx)) {
 		err = damon_sysfs_update_target_pid(target, sys_target->pid);
@@ -1203,8 +1203,10 @@ static int damon_sysfs_set_targets(struct damon_ctx *ctx,
 
 	damon_for_each_target_safe(t, next, ctx) {
 		if (i < sysfs_targets->nr) {
-			damon_sysfs_update_target(t, ctx,
+			err = damon_sysfs_update_target(t, ctx,
 					sysfs_targets->targets_arr[i]);
+			if (err)
+				return err;
 		} else {
 			if (damon_target_has_pid(ctx))
 				put_pid(t->pid);

mm/filemap.c

@@ -3443,7 +3443,7 @@ static vm_fault_t filemap_map_folio_range(struct vm_fault *vmf,
 		 * handled in the specific fault path, and it'll prohibit the
 		 * fault-around logic.
 		 */
-		if (!pte_none(vmf->pte[count]))
+		if (!pte_none(ptep_get(&vmf->pte[count])))
 			goto skip;
 
 		count++;

mm/huge_memory.c

@@ -2769,13 +2769,15 @@ int split_huge_page_to_list(struct page *page, struct list_head *list)
 			int nr = folio_nr_pages(folio);
 
 			xas_split(&xas, folio, folio_order(folio));
-			if (folio_test_swapbacked(folio)) {
-				__lruvec_stat_mod_folio(folio, NR_SHMEM_THPS,
-							-nr);
-			} else {
-				__lruvec_stat_mod_folio(folio, NR_FILE_THPS,
-							-nr);
-				filemap_nr_thps_dec(mapping);
+			if (folio_test_pmd_mappable(folio)) {
+				if (folio_test_swapbacked(folio)) {
+					__lruvec_stat_mod_folio(folio,
+							NR_SHMEM_THPS, -nr);
+				} else {
+					__lruvec_stat_mod_folio(folio,
+							NR_FILE_THPS, -nr);
+					filemap_nr_thps_dec(mapping);
+				}
 			}
 		}
 

mm/ksm.c

@@ -468,7 +468,7 @@ static int break_ksm_pmd_entry(pmd_t *pmd, unsigned long addr, unsigned long nex
 			page = pfn_swap_entry_to_page(entry);
 	}
 	/* return 1 if the page is an normal ksm page or KSM-placed zero page */
-	ret = (page && PageKsm(page)) || is_ksm_zero_pte(*pte);
+	ret = (page && PageKsm(page)) || is_ksm_zero_pte(ptent);
 	pte_unmap_unlock(pte, ptl);
 	return ret;
 }

mm/memcontrol.c

@@ -2936,7 +2936,8 @@ void mem_cgroup_commit_charge(struct folio *folio, struct mem_cgroup *memcg)
  * Moreover, it should not come from DMA buffer and is not readily
  * reclaimable. So those GFP bits should be masked off.
  */
-#define OBJCGS_CLEAR_MASK	(__GFP_DMA | __GFP_RECLAIMABLE | __GFP_ACCOUNT)
+#define OBJCGS_CLEAR_MASK	(__GFP_DMA | __GFP_RECLAIMABLE | \
+				 __GFP_ACCOUNT | __GFP_NOFAIL)
 
 /*
  * mod_objcg_mlstate() may be called with irq enabled, so

mm/userfaultfd.c

@@ -312,7 +312,7 @@ static int mfill_atomic_pte_poison(pmd_t *dst_pmd,
 
 	ret = -EEXIST;
 	/* Refuse to overwrite any PTE, even a PTE marker (e.g. UFFD WP). */
-	if (!pte_none(*dst_pte))
+	if (!pte_none(ptep_get(dst_pte)))
 		goto out_unlock;
 
 	set_pte_at(dst_mm, dst_addr, dst_pte, _dst_pte);

mm/util.c

@@ -414,6 +414,15 @@ static int mmap_is_legacy(struct rlimit *rlim_stack)
 
 static unsigned long mmap_base(unsigned long rnd, struct rlimit *rlim_stack)
 {
+#ifdef CONFIG_STACK_GROWSUP
+	/*
+	 * For an upwards growing stack the calculation is much simpler.
+	 * Memory for the maximum stack size is reserved at the top of the
+	 * task. mmap_base starts directly below the stack and grows
+	 * downwards.
+	 */
+	return PAGE_ALIGN_DOWN(mmap_upper_limit(rlim_stack) - rnd);
+#else
 	unsigned long gap = rlim_stack->rlim_cur;
 	unsigned long pad = stack_guard_gap;
 
@@ -431,6 +440,7 @@ static unsigned long mmap_base(unsigned long rnd, struct rlimit *rlim_stack)
 		gap = MAX_GAP;
 
 	return PAGE_ALIGN(STACK_TOP - gap - rnd);
+#endif
 }
 
 void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack)

tools/testing/selftests/mm/.gitignore

@@ -45,3 +45,4 @@ mdwe_test
 gup_longterm
 mkdirty
 va_high_addr_switch
+hugetlb_fault_after_madv

tools/testing/selftests/mm/pagemap_ioctl.c

@@ -94,19 +94,19 @@ int init_uffd(void)
 
 	uffd = syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK | UFFD_USER_MODE_ONLY);
 	if (uffd == -1)
-		ksft_exit_fail_msg("uffd syscall failed\n");
+		return uffd;
 
 	uffdio_api.api = UFFD_API;
 	uffdio_api.features = UFFD_FEATURE_WP_UNPOPULATED | UFFD_FEATURE_WP_ASYNC |
 			      UFFD_FEATURE_WP_HUGETLBFS_SHMEM;
 	if (ioctl(uffd, UFFDIO_API, &uffdio_api))
-		ksft_exit_fail_msg("UFFDIO_API\n");
+		return -1;
 
 	if (!(uffdio_api.api & UFFDIO_REGISTER_MODE_WP) ||
 	    !(uffdio_api.features & UFFD_FEATURE_WP_UNPOPULATED) ||
 	    !(uffdio_api.features & UFFD_FEATURE_WP_ASYNC) ||
 	    !(uffdio_api.features & UFFD_FEATURE_WP_HUGETLBFS_SHMEM))
-		ksft_exit_fail_msg("UFFDIO_API error %llu\n", uffdio_api.api);
+		return -1;
 
 	return 0;
 }
@@ -1151,15 +1151,15 @@ int sanity_tests(void)
 	/* 9. Memory mapped file */
 	fd = open(__FILE__, O_RDONLY);
 	if (fd < 0)
-		ksft_exit_fail_msg("%s Memory mapped file\n");
+		ksft_exit_fail_msg("%s Memory mapped file\n", __func__);
 
 	ret = stat(__FILE__, &sbuf);
 	if (ret < 0)
 		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
 
 	fmem = mmap(NULL, sbuf.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
 	if (fmem == MAP_FAILED)
-		ksft_exit_fail_msg("error nomem %ld %s\n", errno, strerror(errno));
+		ksft_exit_fail_msg("error nomem %d %s\n", errno, strerror(errno));
 
 	tmp_buf = malloc(sbuf.st_size);
 	memcpy(tmp_buf, fmem, sbuf.st_size);
@@ -1189,7 +1189,7 @@ int sanity_tests(void)
 
 	fmem = mmap(NULL, buf_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
 	if (fmem == MAP_FAILED)
-		ksft_exit_fail_msg("error nomem %ld %s\n", errno, strerror(errno));
+		ksft_exit_fail_msg("error nomem %d %s\n", errno, strerror(errno));
 
 	wp_init(fmem, buf_size);
 	wp_addr_range(fmem, buf_size);
@@ -1479,6 +1479,10 @@ int main(void)
 	struct stat sbuf;
 
 	ksft_print_header();
+
+	if (init_uffd())
+		return ksft_exit_pass();
+
 	ksft_set_plan(115);
 
 	page_size = getpagesize();
@@ -1488,9 +1492,6 @@ int main(void)
 	if (pagemap_fd < 0)
 		return -EINVAL;
 
-	if (init_uffd())
-		ksft_exit_fail_msg("uffd init failed\n");
-
 	/* 1. Sanity testing */
 	sanity_tests_sd();
 
@@ -1595,7 +1596,7 @@ int main(void)
 
 	fmem = mmap(NULL, sbuf.st_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
 	if (fmem == MAP_FAILED)
-		ksft_exit_fail_msg("error nomem %ld %s\n", errno, strerror(errno));
+		ksft_exit_fail_msg("error nomem %d %s\n", errno, strerror(errno));
 
 	wp_init(fmem, sbuf.st_size);
 	wp_addr_range(fmem, sbuf.st_size);
@@ -1623,7 +1624,7 @@ int main(void)
 
 	fmem = mmap(NULL, buf_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
 	if (fmem == MAP_FAILED)
-		ksft_exit_fail_msg("error nomem %ld %s\n", errno, strerror(errno));
+		ksft_exit_fail_msg("error nomem %d %s\n", errno, strerror(errno));
 
 	wp_init(fmem, buf_size);
 	wp_addr_range(fmem, buf_size);

tools/testing/selftests/mm/run_vmtests.sh

@@ -223,9 +223,12 @@ CATEGORY="hugetlb" run_test ./hugepage-mremap
 CATEGORY="hugetlb" run_test ./hugepage-vmemmap
 CATEGORY="hugetlb" run_test ./hugetlb-madvise
 
+nr_hugepages_tmp=$(cat /proc/sys/vm/nr_hugepages)
 # For this test, we need one and just one huge page
 echo 1 > /proc/sys/vm/nr_hugepages
 CATEGORY="hugetlb" run_test ./hugetlb_fault_after_madv
+# Restore the previous number of huge pages, since further tests rely on it
+echo "$nr_hugepages_tmp" > /proc/sys/vm/nr_hugepages
 
 if test_selected "hugetlb"; then
 	echo "NOTE: These hugetlb tests provide minimal coverage.  Use"