Re: [PATCH net-next 1/3] enetc: Add mdio bus driver for the PCIe MDIO endpoint

From: Andrew Lunn
Date: Tue Jul 23 2019 - 18:25:04 EST

> + bus = mdiobus_alloc_size(sizeof(u32 *));
> + if (!bus)
> + return -ENOMEM;
> +

> + bus->priv = pci_iomap_range(pdev, 0, ENETC_MDIO_REG_OFFSET, 0);

This got me confused for a while. You allocate space for a u32
pointer. bus->priv will point to this space. However, you are not
using this space, you {ab}use the pointer to directly hold the return
from pci_iomap_range(). This works, but sparse is probably unhappy,
and you are wasting the space the u32 pointer takes.