- struct ftrace_insn orig, new, old;
-
- if (ftrace_shared_hotpatch_trampoline(NULL)) {
- brcl_disable((void *)rec->ip);
- return 0;
- }
-
- if (copy_from_kernel_nofault(&old, (void *) rec->ip, sizeof(old)))
- return -EFAULT;
- /* Replace ftrace call with a nop. */
- ftrace_generate_call_insn(&orig, rec->ip);
- ftrace_generate_nop_insn(&new);
-
- /* Verify that the to be replaced code matches what we expect. */
- if (memcmp(&orig, &old, sizeof(old)))
- return -EINVAL;
- s390_kernel_write((void *) rec->ip, &new, sizeof(new));