What is the ruling on raising one's voice with supplication or Quran recitation at graves?

It was part of the Prophet's guidance (peace be upon him) to supplicate for the dead and the living when visiting graves, saying: "Peace be upon you, O inhabitants of the dwellings, among the believers and Muslims. May Allah have mercy upon those who have gone ahead of us and those who will come later. And indeed, if Allah wills, we shall join you," and "We ask Allah for well-being for us and for you." However, supplicating to the dead and seeking benefit or warding off harm from them is major shirk (polytheism). Scholars have differed regarding reading the Qur'an at graves, and the preponderant opinion is that it is disliked because it was not reported from the Prophet (peace be upon him), who used to command seeking forgiveness for the deceased and asking for steadfastness for them after burial. Reciting the Qur'an and raising voices with it in cemeteries is considered an innovation.