For this patch, we need to add below to fixup the rv32 call rv64 elf segment fault. diff --git a/arch/riscv/include/asm/processor.h b/arch/riscv/include/asm/processor.h index 0749924d9e55..21c8072dce17 100644 --- a/arch/riscv/include/asm/processor.h +++ b/arch/riscv/include/asm/processor.h @@ -19,7 +19,11 @@ #define TASK_UNMAPPED_BASE PAGE_ALIGN(TASK_SIZE / 3) #define STACK_TOP TASK_SIZE -#define STACK_TOP_MAX STACK_TOP +#ifdef CONFIG_64BIT +#define STACK_TOP_MAX TASK_SIZE_64 +#else +#define STACK_TOP_MAX TASK_SIZE +#endif #define STACK_ALIGN 16 #ifndef __ASSEMBLY__ On Wed, Mar 16, 2022 at 3:04 PM <guoren@xxxxxxxxxx> wrote: > > From: Guo Ren <guoren@xxxxxxxxxxxxxxxxx> > > Make TASK_SIZE from const to dynamic detect TIF_32BIT flag > function. Refer to arm64 to implement DEFAULT_MAP_WINDOW_64 for > efi-stub. > > Limit 32-bit compatible process in 0-2GB virtual address range > (which is enough for real scenarios), because it could avoid > address sign extend problem when 32-bit enter 64-bit and ease > software design. > > The standard 32-bit TASK_SIZE is 0x9dc00000:FIXADDR_START, and > compared to a compatible 32-bit, it increases 476MB for the > application's virtual address. > > Signed-off-by: Guo Ren <guoren@xxxxxxxxxxxxxxxxx> > Signed-off-by: Guo Ren <guoren@xxxxxxxxxx> > Reviewed-by: Arnd Bergmann <arnd@xxxxxxxx> > Tested-by: Heiko Stuebner <heiko@xxxxxxxxx> > --- > arch/riscv/include/asm/pgtable.h | 13 +++++++++++-- > 1 file changed, 11 insertions(+), 2 deletions(-) > > diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h > index e3549e50de95..afdc9ece2ba4 100644 > --- a/arch/riscv/include/asm/pgtable.h > +++ b/arch/riscv/include/asm/pgtable.h > @@ -705,8 +705,17 @@ static inline pmd_t pmdp_establish(struct vm_area_struct *vma, > * 63–48 all equal to bit 47, or else a page-fault exception will occur." > */ > #ifdef CONFIG_64BIT > -#define TASK_SIZE (PGDIR_SIZE * PTRS_PER_PGD / 2) > -#define TASK_SIZE_MIN (PGDIR_SIZE_L3 * PTRS_PER_PGD / 2) > +#define TASK_SIZE_64 (PGDIR_SIZE * PTRS_PER_PGD / 2) > +#define TASK_SIZE_MIN (PGDIR_SIZE_L3 * PTRS_PER_PGD / 2) > + > +#ifdef CONFIG_COMPAT > +#define TASK_SIZE_32 (_AC(0x80000000, UL) - PAGE_SIZE) > +#define TASK_SIZE (test_thread_flag(TIF_32BIT) ? \ > + TASK_SIZE_32 : TASK_SIZE_64) > +#else > +#define TASK_SIZE TASK_SIZE_64 > +#endif > + > #else > #define TASK_SIZE FIXADDR_START > #define TASK_SIZE_MIN TASK_SIZE > -- > 2.25.1 > -- Best Regards Guo Ren ML: https://lore.kernel.org/linux-csky/