324     fn pad_zero(&self, elf_bss: VirtAddr) -> Result<(), SystemError> {  in pad_zero()
325         let nbyte = self.elf_page_offset(elf_bss);  in pad_zero()
328             unsafe { clear_user(elf_bss, nbyte).map_err(|_| SystemError::EFAULT) }?;  in pad_zero()
510         let mut elf_bss = VirtAddr::new(0);  in load()  localVariable
526             if unlikely(elf_brk > elf_bss) {  in load()
534                     elf_bss + load_bias,  in load()
538                 let nbyte = self.elf_page_offset(elf_bss);  in load()
540                     let nbyte = min(Self::ELF_PAGE_SIZE - nbyte, elf_brk - elf_bss);  in load()
544                         clear_user(elf_bss + load_bias, nbyte).ok();  in load()
645             if seg_end_vaddr_f > elf_bss {  in load()
646                 elf_bss = seg_end_vaddr_f;  in load()
679         elf_bss += load_bias;  in load()
692         self.set_elf_brk(&mut user_vm, elf_bss, elf_brk, bss_prot_flags)?;  in load()
694         if likely(elf_bss != elf_brk) && unlikely(self.pad_zero(elf_bss).is_err()) {  in load()
696             return Err(ExecError::BadAddress(Some(elf_bss)));  in load()