| Message ID | 1334586925-11348-1-git-send-email-christian.riesch@omicron.at |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
From: Christian Riesch <christian.riesch@omicron.at> Date: Mon, 16 Apr 2012 16:35:25 +0200 > Under heavy load (flood ping) it is possible for the MDIO timeout to > expire before the loop checks the GO bit again. This patch adds an > additional check whether the operation was done before actually > returning -ETIMEDOUT. > > To reproduce this bug, flood ping the device, e.g., ping -f -l 1000 > After some time, a "timed out waiting for user access" warning > may appear. And even worse, link may go down since the PHY reported a > timeout. > > Signed-off-by: Christian Riesch <christian.riesch@omicron.at> > Cc: <stable@vger.kernel.org> > Cc: Cyril Chemparathy <cyril@ti.com> Applied. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/net/ethernet/ti/davinci_mdio.c b/drivers/net/ethernet/ti/davinci_mdio.c index 2757c7d..e4e4708 100644 --- a/drivers/net/ethernet/ti/davinci_mdio.c +++ b/drivers/net/ethernet/ti/davinci_mdio.c @@ -181,6 +181,11 @@ static inline int wait_for_user_access(struct davinci_mdio_data *data) __davinci_mdio_reset(data); return -EAGAIN; } + + reg = __raw_readl(®s->user[0].access); + if ((reg & USERACCESS_GO) == 0) + return 0; + dev_err(data->dev, "timed out waiting for user access\n"); return -ETIMEDOUT; }
Under heavy load (flood ping) it is possible for the MDIO timeout to expire before the loop checks the GO bit again. This patch adds an additional check whether the operation was done before actually returning -ETIMEDOUT. To reproduce this bug, flood ping the device, e.g., ping -f -l 1000 After some time, a "timed out waiting for user access" warning may appear. And even worse, link may go down since the PHY reported a timeout. Signed-off-by: Christian Riesch <christian.riesch@omicron.at> Cc: <stable@vger.kernel.org> Cc: Cyril Chemparathy <cyril@ti.com> --- drivers/net/ethernet/ti/davinci_mdio.c | 5 +++++ 1 files changed, 5 insertions(+), 0 deletions(-)