Musannaf Ibn Abi Shayba 33:394

Abu Khalid al-Ahmar narrated to us, from Hisham, from his father, who said: Umar ibn al-Khattab entered upon Abu Ubaydah ibn al-Jarrah, and behold, he was lying on the saddlecloth of his mount, using his saddlebag as a pillow. He said: So Umar said to him, "Will you not provide for yourself what your companions have provided for themselves?" He said: "O Commander of the Faithful, this is sufficient for me to reach my resting place."