lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Fri, 12 Jan 2018 22:01:07 +0100 From: Andrew Lunn <andrew@...n.ch> To: Heiner Kallweit <hkallweit1@...il.com> Cc: Florian Fainelli <f.fainelli@...il.com>, "netdev@...r.kernel.org" <netdev@...r.kernel.org> Subject: Re: [PATCH] phy: realtek: use new helpers for paged register access On Fri, Jan 12, 2018 at 09:30:08PM +0100, Heiner Kallweit wrote: > Make use of the new helpers for paged register access. > > Signed-off-by: Heiner Kallweit <hkallweit1@...il.com> > --- > drivers/net/phy/realtek.c | 59 +++++++++++------------------------------------ > 1 file changed, 14 insertions(+), 45 deletions(-) > > diff --git a/drivers/net/phy/realtek.c b/drivers/net/phy/realtek.c > index 7c1bf688d..887bad07a 100644 > --- a/drivers/net/phy/realtek.c > +++ b/drivers/net/phy/realtek.c > @@ -41,37 +41,14 @@ MODULE_DESCRIPTION("Realtek PHY driver"); > MODULE_AUTHOR("Johnson Leung"); > MODULE_LICENSE("GPL"); > > -static int rtl8211x_page_read(struct phy_device *phydev, u16 page, u16 address) > +static int rtl821x_read_page(struct phy_device *phydev) > { > - int ret; > - > - ret = phy_write(phydev, RTL821x_PAGE_SELECT, page); > - if (ret) > - return ret; > - > - ret = phy_read(phydev, address); > - > - /* restore to default page 0 */ > - phy_write(phydev, RTL821x_PAGE_SELECT, 0x0); > - > - return ret; > + return phy_read(phydev, RTL821x_PAGE_SELECT); Hi Heiner It think this is wrong. You need to use __phy_read(). phy_read() does an mdiobus_read(), which takes the bus->mdio_lock. However, int phy_save_page(struct phy_device *phydev) { mutex_lock(&phydev->mdio.bus->mdio_lock); return __phy_read_page(phydev); } This also takes the same lock. So this should deadlock. Try turning on CONFIG_PROVE_LOCKING, it will detect problems like this. Andrew
Powered by blists - more mailing lists