[PATCH v3 06/10] mm/kasan: Use pXd_leaf() in shadow_mapped()

[pet...@redhat.com]

From: Peter Xu <pet...@redhat.com>

There is an old trick in shadow_mapped() to use pXd_bad() to detect huge
pages. After commit 93fab1b22ef7 ("mm: add generic p?d_leaf() macros") we
have a global API for huge mappings. Use that to replace the trick.

Cc: Andrey Ryabinin <ryabin...@gmail.com>
Cc: Alexander Potapenko <gli...@google.com>
Cc: Andrey Konovalov <andre...@gmail.com>
Cc: Dmitry Vyukov <dvy...@google.com>
Cc: Vincenzo Frascino <vincenzo...@arm.com>
Cc: kasa...@googlegroups.com
Signed-off-by: Peter Xu <pet...@redhat.com>
---
mm/kasan/shadow.c | 11 ++---------
1 file changed, 2 insertions(+), 9 deletions(-)

diff --git a/mm/kasan/shadow.c b/mm/kasan/shadow.c
index 9ef84f31833f..d6210ca48dda 100644
--- a/mm/kasan/shadow.c
+++ b/mm/kasan/shadow.c
@@ -199,19 +199,12 @@ static bool shadow_mapped(unsigned long addr)
pud = pud_offset(p4d, addr);
if (pud_none(*pud))
return false;
-
- /*
- * We can't use pud_large() or pud_huge(), the first one is
- * arch-specific, the last one depends on HUGETLB_PAGE. So let's abuse
- * pud_bad(), if pud is bad then it's bad because it's huge.
- */
- if (pud_bad(*pud))
+ if (pud_leaf(*pud))
return true;
pmd = pmd_offset(pud, addr);
if (pmd_none(*pmd))
return false;
-
- if (pmd_bad(*pmd))
+ if (pmd_leaf(*pmd))
return true;
pte = pte_offset_kernel(pmd, addr);
return !pte_none(ptep_get(pte));
--
2.44.0

[Mike Rapoport]

On Tue, Mar 05, 2024 at 12:37:46PM +0800, pet...@redhat.com wrote:
> From: Peter Xu <pet...@redhat.com>
>
> There is an old trick in shadow_mapped() to use pXd_bad() to detect huge
> pages. After commit 93fab1b22ef7 ("mm: add generic p?d_leaf() macros") we
> have a global API for huge mappings. Use that to replace the trick.
>
> Cc: Andrey Ryabinin <ryabin...@gmail.com>
> Cc: Alexander Potapenko <gli...@google.com>
> Cc: Andrey Konovalov <andre...@gmail.com>
> Cc: Dmitry Vyukov <dvy...@google.com>
> Cc: Vincenzo Frascino <vincenzo...@arm.com>
> Cc: kasa...@googlegroups.com
> Signed-off-by: Peter Xu <pet...@redhat.com>

Reviewed-by: Mike Rapoport (IBM) <rp...@kernel.org>

--
Sincerely yours,
Mike.