1 #ifndef __X86_PERCPU_H__ 2 #define __X86_PERCPU_H__ 3 4 #define PARK_OFFLINE_CPUS_VAR 5 6 /* 7 * Force uses of per_cpu() with an invalid area to attempt to access the 8 * middle of the non-canonical address space resulting in a #GP, rather than a 9 * possible #PF at (NULL + a little) which has security implications in the 10 * context of PV guests. 11 */ 12 #define INVALID_PERCPU_AREA (0x8000000000000000UL - (unsigned long)__per_cpu_start) 13 14 #endif /* __X86_PERCPU_H__ */ 15