// SPDX-License-Identifier: GPL-2.0 #include int arch_check_ftrace_location(struct kprobe *p) { if (ftrace_location((unsigned long)p->addr)) p->flags |= KPROBE_FLAG_FTRACE; return 0; } /* Ftrace callback handler for kprobes -- called under preepmt disabed */ void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *ops, struct pt_regs *regs) { bool lr_saver = false; struct kprobe *p; struct kprobe_ctlblk *kcb; /* Preempt is disabled by ftrace */ p = get_kprobe((kprobe_opcode_t *)ip); if (!p) { p = get_kprobe((kprobe_opcode_t *)(ip - MCOUNT_INSN_SIZE)); if (unlikely(!p) || kprobe_disabled(p)) return; lr_saver = true; } kcb = get_kprobe_ctlblk(); if (kprobe_running()) { kprobes_inc_nmissed_count(p); } else { unsigned long orig_ip = instruction_pointer(regs); if (lr_saver) ip -= MCOUNT_INSN_SIZE; instruction_pointer_set(regs, ip); __this_cpu_write(current_kprobe, p); kcb->kprobe_status = KPROBE_HIT_ACTIVE; if (!p->pre_handler || !p->pre_handler(p, regs)) { /* * Emulate singlestep (and also recover regs->pc) * as if there is a nop */ instruction_pointer_set(regs, (unsigned long)p->addr + MCOUNT_INSN_SIZE); if (unlikely(p->post_handler)) { kcb->kprobe_status = KPROBE_HIT_SSDONE; p->post_handler(p, regs, 0); } instruction_pointer_set(regs, orig_ip); } /* * If pre_handler returns !0, it changes regs->pc. We have to * skip emulating post_handler. */ __this_cpu_write(current_kprobe, NULL); } } NOKPROBE_SYMBOL(kprobe_ftrace_handler); int arch_prepare_kprobe_ftrace(struct kprobe *p) { p->ainsn.api.insn = NULL; return 0; }