Re: [PATCH v2 net-next 01/15] net: mdio-regmap: permit working with non-MMIO regmaps
From: Vladimir Oltean <vladimir.oltean@nxp.com>
Date: 2026-01-22 13:47:11
Also in:
linux-devicetree, lkml
Subsystem:
ethernet phy library, mdio regmap driver, networking drivers, the rest · Maintainers:
Andrew Lunn, Heiner Kallweit, Maxime Chevallier, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
On Thu, Jan 22, 2026 at 02:13:01PM +0200, Vladimir Oltean wrote:
quoted
quoted
struct mdio_regmap_priv { struct regmap *regmap; + unsigned int base;Hmm... resource_size_t ?Well, regmap_read() takes "unsigned int reg". https://elixir.bootlin.com/linux/v6.18.6/source/include/linux/regmap.h#L1297 So in practice, a truncation will be done somewhere if the register base exceeds unsigned int storage capacity. But I didn't feel that it's worth handling that.
Would this address your feedback?
diff --git a/drivers/net/mdio/mdio-regmap.c b/drivers/net/mdio/mdio-regmap.c
index 2a0e9c519fa3..416ff4e13e8f 100644
--- a/drivers/net/mdio/mdio-regmap.c
+++ b/drivers/net/mdio/mdio-regmap.c@@ -67,8 +67,15 @@ struct mii_bus *devm_mdio_regmap_register(struct device *dev, mr = mii->priv; mr->regmap = config->regmap; mr->valid_addr = config->valid_addr; - if (config->resource) + if (config->resource) { + if (config->resource->start > U32_MAX || + config->resource->end > U32_MAX) { + dev_err(config->parent, + "Resource exceeds regmap API addressing possibilities\n"); + return ERR_PTR(-EINVAL); + } mr->base = config->resource->start; + } mii->name = DRV_NAME; strscpy(mii->id, config->name, MII_BUS_ID_SIZE);
(needs to be replicated in a bunch of other places)