Commit b6c9d5a9 authored Mar 05, 2024 by Peter Xu Committed by Andrew Morton Mar 06, 2024

mm/kasan: use pXd_leaf() in shadow_mapped()

There is an old trick in shadow_mapped() to use pXd_bad() to detect huge
pages.  After commit 93fab1b2 ("mm: add generic p?d_leaf() macros") we
have a global API for huge mappings.  Use that to replace the trick.

Link: https://lkml.kernel.org/r/20240305043750.93762-7-peterx@redhat.com


Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: "Naveen N. Rao" <naveen.n.rao@linux.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

parent 924bd6a8

mm/kasan/shadow.c

+2 −9

Original line number	Diff line number	Diff line
		@@ -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));