1*35de5b06SAndy Lutomirski #ifndef _ASM_X86_TEXT_PATCHING_H 2*35de5b06SAndy Lutomirski #define _ASM_X86_TEXT_PATCHING_H 3*35de5b06SAndy Lutomirski 4*35de5b06SAndy Lutomirski #include <linux/types.h> 5*35de5b06SAndy Lutomirski #include <linux/stddef.h> 6*35de5b06SAndy Lutomirski #include <asm/ptrace.h> 7*35de5b06SAndy Lutomirski 8*35de5b06SAndy Lutomirski struct paravirt_patch_site; 9*35de5b06SAndy Lutomirski #ifdef CONFIG_PARAVIRT 10*35de5b06SAndy Lutomirski void apply_paravirt(struct paravirt_patch_site *start, 11*35de5b06SAndy Lutomirski struct paravirt_patch_site *end); 12*35de5b06SAndy Lutomirski #else 13*35de5b06SAndy Lutomirski static inline void apply_paravirt(struct paravirt_patch_site *start, 14*35de5b06SAndy Lutomirski struct paravirt_patch_site *end) 15*35de5b06SAndy Lutomirski {} 16*35de5b06SAndy Lutomirski #define __parainstructions NULL 17*35de5b06SAndy Lutomirski #define __parainstructions_end NULL 18*35de5b06SAndy Lutomirski #endif 19*35de5b06SAndy Lutomirski 20*35de5b06SAndy Lutomirski extern void *text_poke_early(void *addr, const void *opcode, size_t len); 21*35de5b06SAndy Lutomirski 22*35de5b06SAndy Lutomirski /* 23*35de5b06SAndy Lutomirski * Clear and restore the kernel write-protection flag on the local CPU. 24*35de5b06SAndy Lutomirski * Allows the kernel to edit read-only pages. 25*35de5b06SAndy Lutomirski * Side-effect: any interrupt handler running between save and restore will have 26*35de5b06SAndy Lutomirski * the ability to write to read-only pages. 27*35de5b06SAndy Lutomirski * 28*35de5b06SAndy Lutomirski * Warning: 29*35de5b06SAndy Lutomirski * Code patching in the UP case is safe if NMIs and MCE handlers are stopped and 30*35de5b06SAndy Lutomirski * no thread can be preempted in the instructions being modified (no iret to an 31*35de5b06SAndy Lutomirski * invalid instruction possible) or if the instructions are changed from a 32*35de5b06SAndy Lutomirski * consistent state to another consistent state atomically. 33*35de5b06SAndy Lutomirski * On the local CPU you need to be protected again NMI or MCE handlers seeing an 34*35de5b06SAndy Lutomirski * inconsistent instruction while you patch. 35*35de5b06SAndy Lutomirski */ 36*35de5b06SAndy Lutomirski extern void *text_poke(void *addr, const void *opcode, size_t len); 37*35de5b06SAndy Lutomirski extern int poke_int3_handler(struct pt_regs *regs); 38*35de5b06SAndy Lutomirski extern void *text_poke_bp(void *addr, const void *opcode, size_t len, void *handler); 39*35de5b06SAndy Lutomirski 40*35de5b06SAndy Lutomirski #endif /* _ASM_X86_TEXT_PATCHING_H */ 41