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Diffstat (limited to 'arch/x86/include/asm/text-patching.h')
-rw-r--r--arch/x86/include/asm/text-patching.h30
1 files changed, 30 insertions, 0 deletions
diff --git a/arch/x86/include/asm/text-patching.h b/arch/x86/include/asm/text-patching.h
index c90678fd391a..880b5515b1d6 100644
--- a/arch/x86/include/asm/text-patching.h
+++ b/arch/x86/include/asm/text-patching.h
@@ -42,4 +42,34 @@ extern int after_bootmem;
extern __ro_after_init struct mm_struct *poking_mm;
extern __ro_after_init unsigned long poking_addr;
+#ifndef CONFIG_UML_X86
+static inline void int3_emulate_jmp(struct pt_regs *regs, unsigned long ip)
+{
+ regs->ip = ip;
+}
+
+#define INT3_INSN_SIZE 1
+#define CALL_INSN_SIZE 5
+
+#ifdef CONFIG_X86_64
+static inline void int3_emulate_push(struct pt_regs *regs, unsigned long val)
+{
+ /*
+ * The int3 handler in entry_64.S adds a gap between the
+ * stack where the break point happened, and the saving of
+ * pt_regs. We can extend the original stack because of
+ * this gap. See the idtentry macro's create_gap option.
+ */
+ regs->sp -= sizeof(unsigned long);
+ *(unsigned long *)regs->sp = val;
+}
+
+static inline void int3_emulate_call(struct pt_regs *regs, unsigned long func)
+{
+ int3_emulate_push(regs, regs->ip - INT3_INSN_SIZE + CALL_INSN_SIZE);
+ int3_emulate_jmp(regs, func);
+}
+#endif /* CONFIG_X86_64 */
+#endif /* !CONFIG_UML_X86 */
+
#endif /* _ASM_X86_TEXT_PATCHING_H */