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// SPDX-License-Identifier: GPL-2.0
#include <linux/kprobes.h>
/* 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 ftrace_regs *regs)
{
struct kprobe *p;
struct kprobe_ctlblk *kcb;
p = get_kprobe((kprobe_opcode_t *)ip);
if (unlikely(!p) || kprobe_disabled(p))
return;
kcb = get_kprobe_ctlblk();
if (kprobe_running()) {
kprobes_inc_nmissed_count(p);
} else {
unsigned long orig_ip = instruction_pointer(&(regs->regs));
instruction_pointer_set(&(regs->regs), ip);
__this_cpu_write(current_kprobe, p);
kcb->kprobe_status = KPROBE_HIT_ACTIVE;
if (!p->pre_handler || !p->pre_handler(p, &(regs->regs))) {
/*
* Emulate singlestep (and also recover regs->pc)
* as if there is a nop
*/
instruction_pointer_set(&(regs->regs),
(unsigned long)p->addr + MCOUNT_INSN_SIZE);
if (unlikely(p->post_handler)) {
kcb->kprobe_status = KPROBE_HIT_SSDONE;
p->post_handler(p, &(regs->regs), 0);
}
instruction_pointer_set(&(regs->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;
}
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