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| author | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-11-21 12:21:53 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-11-21 12:21:53 +0300 |
| commit | 05df6ab8eba625a1d97eb67ee06d786b8e460685 (patch) | |
| tree | 7fed59b7f49fd8d816475ca6b20c95c7f837ca6f /mm/madvise.c | |
| parent | 1d926e259d8f8195fdfaeea7951149001894b473 (diff) | |
| parent | eb7081409f94a9a8608593d0fb63a1aa3d6f95d8 (diff) | |
| download | linux-05df6ab8eba625a1d97eb67ee06d786b8e460685.tar.xz | |
Merge 6.1-rc6 into driver-core-next
We need the kernfs changes in here as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'mm/madvise.c')
| -rw-r--r-- | mm/madvise.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/mm/madvise.c b/mm/madvise.c index 2baa93ca2310..c7105ec6d08c 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -813,7 +813,14 @@ static bool madvise_dontneed_free_valid_vma(struct vm_area_struct *vma, if (start & ~huge_page_mask(hstate_vma(vma))) return false; - *end = ALIGN(*end, huge_page_size(hstate_vma(vma))); + /* + * Madvise callers expect the length to be rounded up to PAGE_SIZE + * boundaries, and may be unaware that this VMA uses huge pages. + * Avoid unexpected data loss by rounding down the number of + * huge pages freed. + */ + *end = ALIGN_DOWN(*end, huge_page_size(hstate_vma(vma))); + return true; } @@ -828,6 +835,9 @@ static long madvise_dontneed_free(struct vm_area_struct *vma, if (!madvise_dontneed_free_valid_vma(vma, start, &end, behavior)) return -EINVAL; + if (start == end) + return 0; + if (!userfaultfd_remove(vma, start, end)) { *prev = NULL; /* mmap_lock has been dropped, prev is stale */ |