/* SPDX-License-Identifier: GPL-2.0 */ #ifndef _ASM_X86_TEXT_PATCHING_H #define _ASM_X86_TEXT_PATCHING_H #include <linux/types.h> #include <linux/stddef.h> #include <asm/ptrace.h> struct paravirt_patch_site; #ifdef CONFIG_PARAVIRT void apply_paravirt(struct paravirt_patch_site *start, struct paravirt_patch_site *end); #else static inline void apply_paravirt(struct paravirt_patch_site *start, struct paravirt_patch_site *end) {} #define __parainstructions NULL #define __parainstructions_end NULL #endif extern void *text_poke_early(void *addr, const void *opcode, size_t len); /* * Clear and restore the kernel write-protection flag on the local CPU. * Allows the kernel to edit read-only pages. * Side-effect: any interrupt handler running between save and restore will have * the ability to write to read-only pages. * * Warning: * Code patching in the UP case is safe if NMIs and MCE handlers are stopped and * no thread can be preempted in the instructions being modified (no iret to an * invalid instruction possible) or if the instructions are changed from a * consistent state to another consistent state atomically. * On the local CPU you need to be protected again NMI or MCE handlers seeing an * inconsistent instruction while you patch. */ extern void *text_poke(void *addr, const void *opcode, size_t len); extern int poke_int3_handler(struct pt_regs *regs); extern void *text_poke_bp(void *addr, const void *opcode, size_t len, void *handler); extern int after_bootmem; #endif /* _ASM_X86_TEXT_PATCHING_H */