projects/linux·commit 23bc8f69

arm64: mm: fix p?d_leaf()

23bc8f69 · Muchun Song <[email protected]> · 2022-04-22 14:00:33 +08:00

The pmd_leaf() is used to test a leaf mapped PMD, however, it misses
the PROT_NONE mapped PMD on arm64.  Fix it.  A real world issue [1]
caused by this was reported by Qian Cai. Also fix pud_leaf().

Link: https://patchwork.kernel.org/comment/24798260/ [1]
Fixes: 8aa82df3c123 ("arm64: mm: add p?d_leaf() definitions")
Reported-by: Qian Cai <[email protected]>
Signed-off-by: Muchun Song <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Will Deacon <[email protected]>
Commit
23bc8f69f0eceecbb87c3801d2e48827d2dca92b
Parents
0ff74a23

Changes

1 files changed · +2 −2

FileStatusAddDelContent
arch/arm64/include/asm/pgtable.hmodified+2−2View file

arch/arm64/include/asm/pgtable.h

View file
diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index 94e147e..dff2b48 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -535,7 +535,7 @@ extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
PMD_TYPE_TABLE)
#define pmd_sect(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
PMD_TYPE_SECT)
-#define pmd_leaf(pmd) pmd_sect(pmd)
+#define pmd_leaf(pmd) (pmd_present(pmd) && !pmd_table(pmd))
#define pmd_bad(pmd) (!pmd_table(pmd))
#define pmd_leaf_size(pmd) (pmd_cont(pmd) ? CONT_PMD_SIZE : PMD_SIZE)
@@ -625,7 +625,7 @@ static inline unsigned long pmd_page_vaddr(pmd_t pmd)
#define pud_none(pud) (!pud_val(pud))
#define pud_bad(pud) (!pud_table(pud))
#define pud_present(pud) pte_present(pud_pte(pud))
-#define pud_leaf(pud) pud_sect(pud)
+#define pud_leaf(pud) (pud_present(pud) && !pud_table(pud))
#define pud_valid(pud) pte_valid(pud_pte(pud))
static inline void set_pud(pud_t *pudp, pud_t pud)