arm64/mm: Check PUD_TYPE_TABLE in pud_bad()

[ Upstream commit bfb1d2b9021c21891427acc86eb848ccedeb274e ]

pud_bad() is currently defined in terms of pud_table(). Although for some
configs, pud_table() is hard-coded to true i.e. when using 64K base pages
or when page table levels are less than 3.

pud_bad() is intended to check that the pud is configured correctly. Hence
let's open-code the same check that the full version of pud_table() uses
into pud_bad(). Then it always performs the check regardless of the config.

Cc: Will Deacon <will@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Link: https://lore.kernel.org/r/20250221044227.1145393-7-anshuman.khandual@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index abf990ce175b1118e4e0b7103ab2bbd83ee9af8a..665f90443f9e8670d96a5efb1eb36fd491bef384 100644 (file)
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -805,7 +805,8 @@ static inline unsigned long pmd_page_vaddr(pmd_t pmd)
        pr_err("%s:%d: bad pmd %016llx.\n", __FILE__, __LINE__, pmd_val(e))
 
 #define pud_none(pud)          (!pud_val(pud))
-#define pud_bad(pud)           (!pud_table(pud))
+#define pud_bad(pud)           ((pud_val(pud) & PUD_TYPE_MASK) != \
+                                PUD_TYPE_TABLE)
 #define pud_present(pud)       pte_present(pud_pte(pud))
 #ifndef __PAGETABLE_PMD_FOLDED
 #define pud_leaf(pud)          (pud_present(pud) && !pud_table(pud))