On 10/17/2014 12:30 PM, Guenter Roeck wrote:
Commit b4d2394d01bc ("dsa: Replace mii_bus with a generic host device") replaces mii_bus with a generic host_dev, and introduces dsa_host_dev_to_mii_bus() to support conversion from host_dev to mii_bus. However, in some cases it uses to_mii_bus to perform that conversion. Since host_dev is not the phy bus device but typically a platform device, this fails and results in a crash with the affected drivers.BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff81781d35>] __mutex_lock_slowpath+0x75/0x100 PGD 406783067 PUD 406784067 PMD 0 Oops: 0002 [#1] SMP ... Call Trace: [<ffffffff810a538b>] ? pick_next_task_fair+0x61b/0x880 [<ffffffff81781de3>] mutex_lock+0x23/0x37 [<ffffffff81533244>] mdiobus_read+0x34/0x60 [<ffffffff8153b95a>] __mv88e6xxx_reg_read+0x8a/0xa0 [<ffffffff8153b9bc>] mv88e6xxx_reg_read+0x4c/0xa0 Fixes: b4d2394d01bc ("dsa: Replace mii_bus with a generic host device") Cc: Alexander Duyck <[email protected]> Signed-off-by: Guenter Roeck <[email protected]> ---
The fix looks good to me. Acked-by: Alexander Duyck <[email protected]> -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
