diff options
| author | Dan Williams <dan.j.williams@intel.com> | 2017-11-29 16:10:18 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-11-29 18:40:42 -0800 |
| commit | c7da82b894e9eef60a04a15f065a8502341bf13b (patch) | |
| tree | c59fd3cca98b6247bcd36f2cea370c3ce746b4e2 /mm/hmm.c | |
| parent | e7fe7b5cae90cf85bb6fed5ec5d4c5cf311a4fe9 (diff) | |
mm: replace pmd_write with pmd_access_permitted in fault + gup paths
The 'access_permitted' helper is used in the gup-fast path and goes
beyond the simple _PAGE_RW check to also:
- validate that the mapping is writable from a protection keys
standpoint
- validate that the pte has _PAGE_USER set since all fault paths where
pmd_write is must be referencing user-memory.
Link: http://lkml.kernel.org/r/151043111049.2842.15241454964150083466.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/hmm.c')
| -rw-r--r-- | mm/hmm.c | 4 |
1 files changed, 2 insertions, 2 deletions
@@ -391,11 +391,11 @@ again: if (pmd_protnone(pmd)) return hmm_vma_walk_clear(start, end, walk); - if (write_fault && !pmd_write(pmd)) + if (!pmd_access_permitted(pmd, write_fault)) return hmm_vma_walk_clear(start, end, walk); pfn = pmd_pfn(pmd) + pte_index(addr); - flag |= pmd_write(pmd) ? HMM_PFN_WRITE : 0; + flag |= pmd_access_permitted(pmd, WRITE) ? HMM_PFN_WRITE : 0; for (; addr < end; addr += PAGE_SIZE, i++, pfn++) pfns[i] = hmm_pfn_t_from_pfn(pfn) | flag; return 0; |