__asm__("movl %%cr4,%%eax\n\t" "orl %0,%%eax\n\t" "movl %%eax,%%cr4\n" : : "irg" (mask) :"ax");
cr4 = read_cr4(); cr4 |= mask; write_cr4(cr4);
static inline void set_in_cr4 (unsigned long mask){	mmu_cr4_features |= mask;	__asm__("movl %%cr4,%%eax\n\t"		"orl %0,%%eax\n\t"		"movl %%eax,%%cr4\n"		: : "irg" (mask)		:"ax");}