commiteba2591d99upstream. Instead of directly dereferencing page tables entries, which can cause issues (see commit20a004e7b0("arm64: mm: Use READ_ONCE/WRITE_ONCE when accessing page tables"), let's introduce new functions to get the pud/p4d/pgd entries (the pte and pmd versions already exist). Note that arm pgd_t is actually an array so pgdp_get() is defined as a macro to avoid a build error. Those new functions will be used in subsequent commits by the riscv architecture. Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com> Link: https://lore.kernel.org/r/20231213203001.179237-3-alexghiti@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com> Signed-off-by: WangYuli <wangyuli@uniontech.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>