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| author | Andrea Arcangeli <aarcange@redhat.com> | 2019-11-30 17:57:58 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-12-01 12:59:10 -0800 |
| commit | 9d4678eb170c4c632174d1fec8ecee31c2f314f9 (patch) | |
| tree | 42c77ee3dd514f345e0cf52b1d5cebe0697a4ed6 /fs/userfaultfd.c | |
| parent | 643aa36eadebdcdcaeecf538f0549a619ad78ea0 (diff) | |
| download | lwn-9d4678eb170c4c632174d1fec8ecee31c2f314f9.tar.gz lwn-9d4678eb170c4c632174d1fec8ecee31c2f314f9.zip | |
fs/userfaultfd.c: wp: clear VM_UFFD_MISSING or VM_UFFD_WP during userfaultfd_register()
If the registration is repeated without VM_UFFD_MISSING or VM_UFFD_WP they
need to be cleared. Currently setting UFFDIO_REGISTER_MODE_WP returns
-EINVAL, so this patch is a noop until the UFFDIO_REGISTER_MODE_WP support
is applied.
Link: http://lkml.kernel.org/r/20191004232834.GP13922@redhat.com
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reported-by: Wei Yang <richardw.yang@linux.intel.com>
Reviewed-by: Wei Yang <richardw.yang@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/userfaultfd.c')
| -rw-r--r-- | fs/userfaultfd.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c index f9fd18670e22..d90c4c5aa3cc 100644 --- a/fs/userfaultfd.c +++ b/fs/userfaultfd.c @@ -1460,7 +1460,8 @@ static int userfaultfd_register(struct userfaultfd_ctx *ctx, start = vma->vm_start; vma_end = min(end, vma->vm_end); - new_flags = (vma->vm_flags & ~vm_flags) | vm_flags; + new_flags = (vma->vm_flags & + ~(VM_UFFD_MISSING|VM_UFFD_WP)) | vm_flags; prev = vma_merge(mm, prev, start, vma_end, new_flags, vma->anon_vma, vma->vm_file, vma->vm_pgoff, vma_policy(vma), |