Re: drivers/net/phy/marvell.c:1037:5-8: WARNING: Unsigned expression compared with zero: val < 0

Re: drivers/net/phy/marvell.c:1037:5-8: WARNING: Unsigned expression compared with zero: val < 0

[Julia Lawall]

Looks like a problem, please check.

julia


> >> drivers/net/phy/marvell.c:1037:5-8: WARNING: Unsigned expression compared with zero: val < 0
>
> git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> git remote update linus
> git checkout d2fa47d9dd5c5f82d78c4503cf33989f67e8aa64
> vim +1037 drivers/net/phy/marvell.c
>
> d2fa47d9 Andrew Lunn 2015-12-30  1021  #define UINT64_MAX              (u64)(~((u64)0))
> d2fa47d9 Andrew Lunn 2015-12-30  1022  #endif
> d2fa47d9 Andrew Lunn 2015-12-30  1023  static u64 marvell_get_stat(struct phy_device *phydev, int i)
> d2fa47d9 Andrew Lunn 2015-12-30  1024  {
> d2fa47d9 Andrew Lunn 2015-12-30  1025  	struct marvell_hw_stat stat = marvell_hw_stats[i];
> d2fa47d9 Andrew Lunn 2015-12-30  1026  	struct marvell_priv *priv = phydev->priv;
> d2fa47d9 Andrew Lunn 2015-12-30  1027  	int err, oldpage;
> d2fa47d9 Andrew Lunn 2015-12-30  1028  	u64 val;
> d2fa47d9 Andrew Lunn 2015-12-30  1029
> d2fa47d9 Andrew Lunn 2015-12-30  1030  	oldpage = phy_read(phydev, MII_MARVELL_PHY_PAGE);
> d2fa47d9 Andrew Lunn 2015-12-30  1031  	err = phy_write(phydev, MII_MARVELL_PHY_PAGE,
> d2fa47d9 Andrew Lunn 2015-12-30  1032  			stat.page);
> d2fa47d9 Andrew Lunn 2015-12-30  1033  	if (err < 0)
> d2fa47d9 Andrew Lunn 2015-12-30  1034  		return UINT64_MAX;
> d2fa47d9 Andrew Lunn 2015-12-30  1035
> d2fa47d9 Andrew Lunn 2015-12-30  1036  	val = phy_read(phydev, stat.reg);
> d2fa47d9 Andrew Lunn 2015-12-30 @1037  	if (val < 0) {
> d2fa47d9 Andrew Lunn 2015-12-30  1038  		val = UINT64_MAX;
> d2fa47d9 Andrew Lunn 2015-12-30  1039  	} else {
> d2fa47d9 Andrew Lunn 2015-12-30  1040  		val = val & ((1 << stat.bits) - 1);
> d2fa47d9 Andrew Lunn 2015-12-30  1041  		priv->stats[i] += val;
> d2fa47d9 Andrew Lunn 2015-12-30  1042  		val = priv->stats[i];
> d2fa47d9 Andrew Lunn 2015-12-30  1043  	}
> d2fa47d9 Andrew Lunn 2015-12-30  1044
> d2fa47d9 Andrew Lunn 2015-12-30  1045  	phy_write(phydev, MII_MARVELL_PHY_PAGE, oldpage);
>
> ---
> 0-DAY kernel test infrastructure                Open Source Technology Center
> https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
>

Re: drivers/net/phy/marvell.c:1037:5-8: WARNING: Unsigned expression compared with zero: val < 0

[Andrew Lunn]

On Wed, Feb 17, 2016 at 08:36:49AM -0500, Julia Lawall wrote:
> Looks like a problem, please check.

Hi Julia

It is, and Dan Carpenter already pointed it out. There is a second phy
driver with the exact same problem. No need to tell me if you find it.

Thanks
       Andrew