From b1a529bdb9641392b4f5fc91545598793c0b3b96 Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Thu, 5 Jun 2025 22:34:31 +0100 Subject: selftests/mm: skip failed memfd setups in gup_longterm Unlike the other cases gup_longterm's memfd tests previously skipped the test when failing to set up the file descriptor to test. Restore this behavior to avoid hitting failures when hugetlb isn't configured. Link: https://lkml.kernel.org/r/20250605-selftest-mm-gup-longterm-tweaks-v1-1-2fae34b05958@kernel.org Fixes: 66bce7afbaca ("selftests/mm: fix test result reporting in gup_longterm") Signed-off-by: Mark Brown Reported-by: Lorenzo Stoakes Closes: https://lkml.kernel.org/r/a76fc252-0fe3-4d4b-a9a1-4a2895c2680d@lucifer.local Reviewed-by: Lorenzo Stoakes Tested-by: Lorenzo Stoakes Acked-by: David Hildenbrand Cc: Shuah Khan Signed-off-by: Andrew Morton --- tools/testing/selftests/mm/gup_longterm.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'tools/testing') diff --git a/tools/testing/selftests/mm/gup_longterm.c b/tools/testing/selftests/mm/gup_longterm.c index 8a97ac5176a4..29047d2e0c49 100644 --- a/tools/testing/selftests/mm/gup_longterm.c +++ b/tools/testing/selftests/mm/gup_longterm.c @@ -298,8 +298,11 @@ static void run_with_memfd(test_fn fn, const char *desc) log_test_start("%s ... with memfd", desc); fd = memfd_create("test", 0); - if (fd < 0) + if (fd < 0) { ksft_print_msg("memfd_create() failed (%s)\n", strerror(errno)); + log_test_result(KSFT_SKIP); + return; + } fn(fd, pagesize); close(fd); @@ -366,6 +369,8 @@ static void run_with_memfd_hugetlb(test_fn fn, const char *desc, fd = memfd_create("test", flags); if (fd < 0) { ksft_print_msg("memfd_create() failed (%s)\n", strerror(errno)); + log_test_result(KSFT_SKIP); + return; } fn(fd, hugetlbsize); -- cgit v1.2.3 From bb666b7c27073b986b75699e51a7102910f58060 Mon Sep 17 00:00:00 2001 From: Lorenzo Stoakes Date: Mon, 9 Jun 2025 17:57:49 +0100 Subject: mm: add mmap_prepare() compatibility layer for nested file systems Nested file systems, that is those which invoke call_mmap() within their own f_op->mmap() handlers, may encounter underlying file systems which provide the f_op->mmap_prepare() hook introduced by commit c84bf6dd2b83 ("mm: introduce new .mmap_prepare() file callback"). We have a chicken-and-egg scenario here - until all file systems are converted to using .mmap_prepare(), we cannot convert these nested handlers, as we can't call f_op->mmap from an .mmap_prepare() hook. So we have to do it the other way round - invoke the .mmap_prepare() hook from an .mmap() one. in order to do so, we need to convert VMA state into a struct vm_area_desc descriptor, invoking the underlying file system's f_op->mmap_prepare() callback passing a pointer to this, and then setting VMA state accordingly and safely. This patch achieves this via the compat_vma_mmap_prepare() function, which we invoke from call_mmap() if f_op->mmap_prepare() is specified in the passed in file pointer. We place the fundamental logic into mm/vma.h where VMA manipulation belongs. We also update the VMA userland tests to accommodate the changes. The compat_vma_mmap_prepare() function and its associated machinery is temporary, and will be removed once the conversion of file systems is complete. We carefully place this code so it can be used with CONFIG_MMU and also with cutting edge nommu silicon. [akpm@linux-foundation.org: export compat_vma_mmap_prepare tp fix build] [lorenzo.stoakes@oracle.com: remove unused declarations] Link: https://lkml.kernel.org/r/ac3ae324-4c65-432a-8c6d-2af988b18ac8@lucifer.local Link: https://lkml.kernel.org/r/20250609165749.344976-1-lorenzo.stoakes@oracle.com Fixes: c84bf6dd2b83 ("mm: introduce new .mmap_prepare() file callback"). Signed-off-by: Lorenzo Stoakes Reported-by: Jann Horn Closes: https://lore.kernel.org/linux-mm/CAG48ez04yOEVx1ekzOChARDDBZzAKwet8PEoPM4Ln3_rk91AzQ@mail.gmail.com/ Reviewed-by: Pedro Falcato Reviewed-by: Vlastimil Babka Cc: Al Viro Cc: Christian Brauner Cc: Jan Kara Cc: Jann Horn Cc: Liam Howlett Signed-off-by: Andrew Morton --- tools/testing/vma/vma_internal.h | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) (limited to 'tools/testing') diff --git a/tools/testing/vma/vma_internal.h b/tools/testing/vma/vma_internal.h index 4505b1c31be1..14718ca23a05 100644 --- a/tools/testing/vma/vma_internal.h +++ b/tools/testing/vma/vma_internal.h @@ -159,6 +159,14 @@ typedef __bitwise unsigned int vm_fault_t; #define ASSERT_EXCLUSIVE_WRITER(x) +/** + * swap - swap values of @a and @b + * @a: first value + * @b: second value + */ +#define swap(a, b) \ + do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0) + struct kref { refcount_t refcount; }; @@ -1468,4 +1476,12 @@ static inline void fixup_hugetlb_reservations(struct vm_area_struct *vma) (void)vma; } +static inline void vma_set_file(struct vm_area_struct *vma, struct file *file) +{ + /* Changing an anonymous vma with this is illegal */ + get_file(file); + swap(vma->vm_file, file); + fput(file); +} + #endif /* __MM_VMA_INTERNAL_H */ -- cgit v1.2.3