TRAMPOLINE_PHYS_LOW 131 arch/x86/kernel/smpboot.c *((volatile unsigned short *)phys_to_virt(TRAMPOLINE_PHYS_LOW)) = TRAMPOLINE_PHYS_LOW 147 arch/x86/kernel/smpboot.c *((volatile u32 *)phys_to_virt(TRAMPOLINE_PHYS_LOW)) = 0;