Merge branch 'mm-hotfixes-unstable' of https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

4 files changed, 58 insertions, 6 deletions

diff --git a/tools/testing/selftests/clone3/clone3_set_tid.c b/tools/testing/selftests/clone3/clone3_set_tid.c
index 5c944aee6b41..485efa7c9eed 100644
--- a/tools/testing/selftests/clone3/clone3_set_tid.c
+++ b/tools/testing/selftests/clone3/clone3_set_tid.c
@@ -141,7 +141,7 @@ int main(int argc, char *argv[])
 {
 	FILE *f;
 	char buf;
-	char *line;
+	char *line = NULL;
 	int status;
 	int ret = -1;
 	size_t len = 0;
diff --git a/tools/testing/selftests/filesystems/fclog.c b/tools/testing/selftests/filesystems/fclog.c
index 551c4a0f395a..593a5136e991 100644
--- a/tools/testing/selftests/filesystems/fclog.c
+++ b/tools/testing/selftests/filesystems/fclog.c
@@ -6,10 +6,8 @@
 
 #include <assert.h>
 #include <errno.h>
+#include <fcntl.h>
 #include <sched.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
 #include <unistd.h>
 #include <sys/mount.h>
 
diff --git a/tools/testing/selftests/mm/mlock-random-test.c b/tools/testing/selftests/mm/mlock-random-test.c
index 9d349c151360..16294bc7dae6 100644
--- a/tools/testing/selftests/mm/mlock-random-test.c
+++ b/tools/testing/selftests/mm/mlock-random-test.c
@@ -84,7 +84,7 @@ int get_proc_locked_vm_size(void)
 int get_proc_page_size(unsigned long addr)
 {
 	FILE *smaps;
-	char *line;
+	char *line = NULL;
 	unsigned long mmupage_size = 0;
 	size_t size;
 
diff --git a/tools/testing/selftests/mm/pagemap_ioctl.c b/tools/testing/selftests/mm/pagemap_ioctl.c
index 6f8971d5b3ce..f9bcff8e78fa 100644
--- a/tools/testing/selftests/mm/pagemap_ioctl.c
+++ b/tools/testing/selftests/mm/pagemap_ioctl.c
@@ -1051,6 +1051,57 @@ static void test_simple(void)
 	ksft_test_result(i == TEST_ITERATIONS, "Test %s\n", __func__);
 }
 
+/*
+ * A range that was populated and then MADV_DONTNEED'd is genuine pte_none
+ * with no uffd-wp marker. Such a pte must read the same regardless of which
+ * PAGEMAP_SCAN path serves the request: both the PAGE_IS_WRITTEN fast path and
+ * the generic path (reached e.g. via category_anyof_mask) must report every
+ * page written.
+ */
+static void unpopulated_scan_test(void)
+{
+	int npages = 16, i;
+	long mem_size = npages * page_size;
+	struct page_region regions[16];
+	long fast = 0, slow = 0, ret;
+	char *mem;
+
+	mem = mmap(NULL, mem_size, PROT_READ | PROT_WRITE,
+		   MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+	if (mem == MAP_FAILED)
+		ksft_exit_fail_msg("%s mmap failed\n", __func__);
+
+	wp_init(mem, mem_size);
+
+	/* Populate, then drop: the ptes become pte_none without a marker. */
+	memset(mem, 1, mem_size);
+	if (madvise(mem, mem_size, MADV_DONTNEED))
+		ksft_exit_fail_msg("%s MADV_DONTNEED failed\n", __func__);
+
+	/* Fast path: category_mask == return_mask == PAGE_IS_WRITTEN. */
+	ret = pagemap_ioctl(mem, mem_size, regions, npages, 0, 0,
+			    PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN);
+	if (ret < 0)
+		ksft_exit_fail_msg("%s fast scan failed\n", __func__);
+	for (i = 0; i < ret; i++)
+		fast += LEN(regions[i]);
+
+	/* Generic path: same query expressed via category_anyof_mask. */
+	ret = pagemap_ioctl(mem, mem_size, regions, npages, 0, 0,
+			    0, PAGE_IS_WRITTEN, 0, PAGE_IS_WRITTEN);
+	if (ret < 0)
+		ksft_exit_fail_msg("%s generic scan failed\n", __func__);
+	for (i = 0; i < ret; i++)
+		slow += LEN(regions[i]);
+
+	ksft_test_result(fast == npages && slow == npages,
+			 "%s unpopulated ptes reported written by both paths (%ld, %ld of %d)\n",
+			 __func__, fast, slow, npages);
+
+	wp_free(mem, mem_size);
+	munmap(mem, mem_size);
+}
+
 int sanity_tests(void)
 {
 	unsigned long long mem_size, vec_size;
@@ -1559,7 +1610,7 @@ int main(int __attribute__((unused)) argc, char *argv[])
 	if (!hugetlb_setup_default(4))
 		ksft_print_msg("HugeTLB test will be skipped\n");
 
-	ksft_set_plan(117);
+	ksft_set_plan(118);
 
 	page_size = getpagesize();
 	hpage_size = read_pmd_pagesize();
@@ -1737,6 +1788,9 @@ int main(int __attribute__((unused)) argc, char *argv[])
 	/* 17. ZEROPFN tests */
 	zeropfn_tests();
 
+	/* 18. Unpopulated pte scan-path consistency */
+	unpopulated_scan_test();
+
 	close(pagemap_fd);
 	ksft_finished();
 }