diff options
| author | Ryan Roberts <ryan.roberts@arm.com> | 2023-11-14 15:49:45 +0000 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2023-11-15 15:30:09 -0800 |
| commit | afccb0804fc74ac2f6737af6a139632606cb461d (patch) | |
| tree | f40e6663e27cc7be0f49900d08d08cfd7c54c397 /mm/userfaultfd.c | |
| parent | 5f74f820f6fc844b95f9e5e406e0a07d97510420 (diff) | |
mm: more ptep_get() conversion
Commit c33c794828f2 ("mm: ptep_get() conversion") converted all (non-arch)
call sites to use ptep_get() instead of doing a direct dereference of the
pte. Full rationale can be found in that commit's log.
Since then, three new call sites have snuck in, which directly dereference
the pte, so let's fix those up.
Unfortunately there is no reliable automated mechanism to catch these; I'm
relying on a combination of Coccinelle (which throws up a lot of false
positives) and some compiler magic to force a compiler error on
dereference (While this approach finds dereferences, it also yields a
non-booting kernel so can't be committed).
Link: https://lkml.kernel.org/r/20231114154945.490401-1-ryan.roberts@arm.com
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm/userfaultfd.c')
| -rw-r--r-- | mm/userfaultfd.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c index 96d9eae5c7cc..0b6ca553bebe 100644 --- a/mm/userfaultfd.c +++ b/mm/userfaultfd.c @@ -312,7 +312,7 @@ static int mfill_atomic_pte_poison(pmd_t *dst_pmd, ret = -EEXIST; /* Refuse to overwrite any PTE, even a PTE marker (e.g. UFFD WP). */ - if (!pte_none(*dst_pte)) + if (!pte_none(ptep_get(dst_pte))) goto out_unlock; set_pte_at(dst_mm, dst_addr, dst_pte, _dst_pte); |