On Mon, 2014-03-10 at 10:49 +0000, Sebastian Hesselbarth wrote:
On 03/10/2014 02:51 AM, Ben Hutchings wrote:
On Mon, 2014-03-10 at 02:01 +0100, Sebastian Hesselbarth wrote:
phy_ethtool_get_wol is a helper to get current WOL settings from
a phy device. When using this helper on a PHY without .get_wol
callback, struct ethtool_wolinfo is never set-up correctly and
may contain misleading information about WOL status.
To fix this, always zero relevant fields of struct ethtool_wolinfo
regardless of .get_wol callback availability.
I think it's the caller's responsibility to zero out struct
ethtool_wolinfo. That is what ethtool_get_wol() does.
Actually, phy_ethtool_get_wol is the caller here. This belongs to
a set of helpers that deal with phy_device, not netdev.
Right, but ethtool_get_wol() is further up the stack and is responsible
for initialising the struct to defaults.
[...]Maybe you could split ethtool_get_wol() like we did
ethtool_get_settings(), to support in-kernel invocation of ETHTOOL_GWOL?
Looking at the other users of phy_ethtool_get_wol (mv643xx_eth and
cpsw), both drivers use this helper to determine what to pass back
on the corresponding ethtool_get_wol call.
BTW, both drivers above do zero ethtool_wolinfo before calling
phy_ethtool_get_wol. I can either zero it in phy_suspend too or we
deal with it properly in phy_ethtool_get_wol instead:
void phy_ethtool_get_wol(struct phy_device *phydev, struct
ethtool_wolinfo *wol)
{
memset(wol, 0, sizeof(*wol));
if (phydev && phydev->drv->get_wol)
phydev->drv->get_wol(phydev, wol);
}
This trashes wol->cmd. Don't do that.