The patch titled
Subject: selftests/mm: smoke test UFFD_FEATURE_WP_UNPOPULATED
has been added to the -mm mm-unstable branch. Its filename is
selftests-mm-smoke-test-uffd_feature_wp_unpopulated.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/selftests-mm-smoke-test-uffd_feature_wp_unpopulated.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: Peter Xu <peterx@xxxxxxxxxx>
Subject: selftests/mm: smoke test UFFD_FEATURE_WP_UNPOPULATED
Date: Thu, 9 Mar 2023 17:37:11 -0500
Enable it by default on the stress test, and add some smoke tests for the
pte markers on anonymous.
Link: https://lkml.kernel.org/r/20230309223711.823547-3-peterx@xxxxxxxxxx
Signed-off-by: Peter Xu <peterx@xxxxxxxxxx>
Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx>
Cc: Axel Rasmussen <axelrasmussen@xxxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: Mike Rapoport <rppt@xxxxxxxxxxxxxxxxxx>
Cc: Muhammad Usama Anjum <usama.anjum@xxxxxxxxxxxxx>
Cc: Nadav Amit <nadav.amit@xxxxxxxxx>
Cc: Paul Gofman <pgofman@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
--- a/tools/testing/selftests/mm/userfaultfd.c~selftests-mm-smoke-test-uffd_feature_wp_unpopulated
+++ a/tools/testing/selftests/mm/userfaultfd.c
@@ -1444,6 +1444,43 @@ static int pagemap_test_fork(bool presen
return result;
}
+static void userfaultfd_wp_unpopulated_test(int pagemap_fd)
+{
+ uint64_t value;
+
+ /* Test applying pte marker to anon unpopulated */
+ wp_range(uffd, (uint64_t)area_dst, page_size, true);
+ value = pagemap_read_vaddr(pagemap_fd, area_dst);
+ pagemap_check_wp(value, true);
+
+ /* Test unprotect on anon pte marker */
+ wp_range(uffd, (uint64_t)area_dst, page_size, false);
+ value = pagemap_read_vaddr(pagemap_fd, area_dst);
+ pagemap_check_wp(value, false);
+
+ /* Test zap on anon marker */
+ wp_range(uffd, (uint64_t)area_dst, page_size, true);
+ if (madvise(area_dst, page_size, MADV_DONTNEED))
+ err("madvise(MADV_DONTNEED) failed");
+ value = pagemap_read_vaddr(pagemap_fd, area_dst);
+ pagemap_check_wp(value, false);
+
+ /* Test fault in after marker removed */
+ *area_dst = 1;
+ value = pagemap_read_vaddr(pagemap_fd, area_dst);
+ pagemap_check_wp(value, false);
+ /* Drop it to make pte none again */
+ if (madvise(area_dst, page_size, MADV_DONTNEED))
+ err("madvise(MADV_DONTNEED) failed");
+
+ /* Test read-zero-page upon pte marker */
+ wp_range(uffd, (uint64_t)area_dst, page_size, true);
+ *(volatile char *)area_dst;
+ /* Drop it to make pte none again */
+ if (madvise(area_dst, page_size, MADV_DONTNEED))
+ err("madvise(MADV_DONTNEED) failed");
+}
+
static void userfaultfd_pagemap_test(unsigned int test_pgsize)
{
struct uffdio_register uffdio_register;
@@ -1462,7 +1499,7 @@ static void userfaultfd_pagemap_test(uns
/* Flush so it doesn't flush twice in parent/child later */
fflush(stdout);
- uffd_test_ctx_init(0);
+ uffd_test_ctx_init(UFFD_FEATURE_WP_UNPOPULATED);
if (test_pgsize > page_size) {
/* This is a thp test */
@@ -1482,6 +1519,10 @@ static void userfaultfd_pagemap_test(uns
pagemap_fd = pagemap_open();
+ /* Smoke test WP_UNPOPULATED first when it's still empty */
+ if (test_pgsize == page_size)
+ userfaultfd_wp_unpopulated_test(pagemap_fd);
+
/* Touch the page */
*area_dst = 1;
wp_range(uffd, (uint64_t)area_dst, test_pgsize, true);
@@ -1526,7 +1567,7 @@ static int userfaultfd_stress(void)
struct uffdio_register uffdio_register;
struct uffd_stats uffd_stats[nr_cpus];
- uffd_test_ctx_init(0);
+ uffd_test_ctx_init(UFFD_FEATURE_WP_UNPOPULATED);
if (posix_memalign(&area, page_size, page_size))
err("out of memory");
_
Patches currently in -mm which might be from peterx@xxxxxxxxxx are
kselftest-vm-fix-unused-variable-warning.patch
tools-headers-uapi-sync-linux-prctlh-with-the-kernel-sources.patch
mm-khugepaged-alloc_charge_hpage-take-care-of-mem-charge-errors.patch
mm-khugepaged-cleanup-memcg-uncharge-for-failure-path.patch
mm-uffd-uffd_feature_wp_unpopulated.patch
selftests-mm-smoke-test-uffd_feature_wp_unpopulated.patch
