path: root/arch
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authorDan Williams <dan.j.williams@intel.com>2017-11-29 16:10:14 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2017-11-29 18:40:42 -0800
commite7fe7b5cae90cf85bb6fed5ec5d4c5cf311a4fe9 (patch)
tree8019ca6ee6cd5adbe2bea8f7313c5601a2f87c7f /arch
parente4e40e0263ea6a3bfefbfd15d1b6ff5c03f2b95e (diff)
mm: replace pud_write with pud_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 pud_write is must be referencing user-memory. [dan.j.williams@intel.com: fix powerpc compile error] Link: http://lkml.kernel.org/r/151129127237.37405.16073414520854722485.stgit@dwillia2-desk3.amr.corp.intel.com Link: http://lkml.kernel.org/r/151043110453.2842.2166049702068628177.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: "David S. Miller" <davem@davemloft.net> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch')
2 files changed, 7 insertions, 1 deletions
diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
index 0a6b0286c32e..57d7bc92e0b8 100644
--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -1264,6 +1264,12 @@ static inline pud_t pud_mkwrite(pud_t pud)
return pud;
+#define pud_write pud_write
+static inline int pud_write(pud_t pud)
+ return (pud_val(pud) & _REGION3_ENTRY_WRITE) != 0;
static inline pud_t pud_mkclean(pud_t pud)
if (pud_large(pud)) {
diff --git a/arch/sparc/mm/gup.c b/arch/sparc/mm/gup.c
index 5335ba3c850e..5ae2d0a01a70 100644
--- a/arch/sparc/mm/gup.c
+++ b/arch/sparc/mm/gup.c
@@ -114,7 +114,7 @@ static int gup_huge_pud(pud_t *pudp, pud_t pud, unsigned long addr,
if (!(pud_val(pud) & _PAGE_VALID))
return 0;
- if (write && !pud_write(pud))
+ if (!pud_access_permitted(pud, write))
return 0;
refs = 0;

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