From: Will Deacon <will@xxxxxxxxxx> [ Upstream commit 4e4ff23a35ee3a145fbc8378ecfeaab2d235cddd ] With only two levels of page-table, the generic 'pud_*' macros are implemented using dummy operations in pgtable-nopmd.h. Since commit 730a11f982e6 ("arm64/mm: add pud_user_exec() check in pud_user_accessible_page()"), pud_user_accessible_page() unconditionally calls pud_user_exec(), which is an arm64-specific helper and therefore isn't defined by pgtable-nopmd.h. This results in a build failure for configurations with only two levels of page table: arch/arm64/include/asm/pgtable.h: In function 'pud_user_accessible_page': >> arch/arm64/include/asm/pgtable.h:870:51: error: implicit declaration of function 'pud_user_exec'; did you mean 'pmd_user_exec'? [-Werror=implicit-function-declaration] 870 | return pud_leaf(pud) && (pud_user(pud) || pud_user_exec(pud)); | ^~~~~~~~~~~~~ | pmd_user_exec Fix the problem by defining pud_user_exec() as pud_user() in this case. Link: https://lore.kernel.org/r/202301080515.z6zEksU4-lkp@xxxxxxxxx Reported-by: kernel test robot <lkp@xxxxxxxxx> Signed-off-by: Will Deacon <will@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- arch/arm64/include/asm/pgtable.h | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index edf6625ce965..c43ecb072ffd 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -731,6 +731,7 @@ static inline pmd_t *pud_pgtable(pud_t pud) #else #define pud_page_paddr(pud) ({ BUILD_BUG(); 0; }) +#define pud_user_exec(pud) pud_user(pud) /* Always 0 with folding */ /* Match pmd_offset folding in <asm/generic/pgtable-nopmd.h> */ #define pmd_set_fixmap(addr) NULL -- 2.35.1