Orange Pi5 kernel

// SPDX-License-Identifier: GPL-2.0-only
/*
 * check_initial_reg_state.c - check that execve sets the correct state
 * Copyright (c) 2014-2016 Andrew Lutomirski
 */
 
#define _GNU_SOURCE
 
#include <stdio.h>
 
unsigned long ax, bx, cx, dx, si, di, bp, sp, flags;
unsigned long r8, r9, r10, r11, r12, r13, r14, r15;
 
asm (
<------>".pushsection .text\n\t"
<------>".type real_start, @function\n\t"
<------>".global real_start\n\t"
<------>"real_start:\n\t"
#ifdef __x86_64__
<------>"mov %rax, ax\n\t"
<------>"mov %rbx, bx\n\t"
<------>"mov %rcx, cx\n\t"
<------>"mov %rdx, dx\n\t"
<------>"mov %rsi, si\n\t"
<------>"mov %rdi, di\n\t"
<------>"mov %rbp, bp\n\t"
<------>"mov %rsp, sp\n\t"
<------>"mov %r8, r8\n\t"
<------>"mov %r9, r9\n\t"
<------>"mov %r10, r10\n\t"
<------>"mov %r11, r11\n\t"
<------>"mov %r12, r12\n\t"
<------>"mov %r13, r13\n\t"
<------>"mov %r14, r14\n\t"
<------>"mov %r15, r15\n\t"
<------>"pushfq\n\t"
<------>"popq flags\n\t"
#else
<------>"mov %eax, ax\n\t"
<------>"mov %ebx, bx\n\t"
<------>"mov %ecx, cx\n\t"
<------>"mov %edx, dx\n\t"
<------>"mov %esi, si\n\t"
<------>"mov %edi, di\n\t"
<------>"mov %ebp, bp\n\t"
<------>"mov %esp, sp\n\t"
<------>"pushfl\n\t"
<------>"popl flags\n\t"
#endif
<------>"jmp _start\n\t"
<------>".size real_start, . - real_start\n\t"
<------>".popsection");
 
int main()
{
<------>int nerrs = 0;
 
<------>if (sp == 0) {
<------><------>printf("[FAIL]\tTest was built incorrectly\n");
<------><------>return 1;
<------>}
 
<------>if (ax || bx || cx || dx || si || di || bp
#ifdef __x86_64__
<------>    || r8 || r9 || r10 || r11 || r12 || r13 || r14 || r15
#endif
<------><------>) {
<------><------>printf("[FAIL]\tAll GPRs except SP should be 0\n");
#define SHOW(x) printf("\t" #x " = 0x%lx\n", x);
<------><------>SHOW(ax);
<------><------>SHOW(bx);
<------><------>SHOW(cx);
<------><------>SHOW(dx);
<------><------>SHOW(si);
<------><------>SHOW(di);
<------><------>SHOW(bp);
<------><------>SHOW(sp);
#ifdef __x86_64__
<------><------>SHOW(r8);
<------><------>SHOW(r9);
<------><------>SHOW(r10);
<------><------>SHOW(r11);
<------><------>SHOW(r12);
<------><------>SHOW(r13);
<------><------>SHOW(r14);
<------><------>SHOW(r15);
#endif
<------><------>nerrs++;
<------>} else {
<------><------>printf("[OK]\tAll GPRs except SP are 0\n");
<------>}
 
<------>if (flags != 0x202) {
<------><------>printf("[FAIL]\tFLAGS is 0x%lx, but it should be 0x202\n", flags);
<------><------>nerrs++;
<------>} else {
<------><------>printf("[OK]\tFLAGS is 0x202\n");
<------>}
 
<------>return nerrs ? 1 : 0;
}