From 4f9c85a1b03bfa5c0a0d8488a3a7766f3c9fb756 Mon Sep 17 00:00:00 2001 From: Anton Vorontsov Date: Mon, 18 Jan 2010 05:37:16 +0000 Subject: phylib: Move workqueue initialization to a proper place commit 541cd3ee00a4fe975b22fac6a3bc846bacef37f7 ("phylib: Fix deadlock on resume") caused TI DaVinci EMAC ethernet driver to oops upon resume: PM: resume of devices complete after 237.098 msecs Restarting tasks ... done. kernel BUG at kernel/workqueue.c:354! Unable to handle kernel NULL pointer dereference at virtual address 00000000 [...] Backtrace: [] (__bug+0x0/0x2c) from [] (queue_delayed_work_on+0x74/0xf8) [] (queue_delayed_work_on+0x0/0xf8) from [] (queue_delayed_work+0x2c/0x30) The oops pops up because TI DaVinci EMAC driver detaches PHY on suspend and attaches it back on resume. Attaching makes phylib call phy_start_machine() that initializes a workqueue. On the other hand, PHY's resume routine will call phy_start_machine() again, and that will cause the oops since we just destroyed the already scheduled workqueue. This patch fixes the issue by moving workqueue initialization to phy_device_create(). p.s. We don't see this oops with ucc_geth and gianfar drivers because they perform a fine-grained suspend, i.e. they just stop the PHYs without detaching. Reported-by: Sekhar Nori Signed-off-by: Anton Vorontsov Tested-by: Sekhar Nori Signed-off-by: David S. Miller --- include/linux/phy.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux') diff --git a/include/linux/phy.h b/include/linux/phy.h index 7968defd2fa7..6a7eb402165d 100644 --- a/include/linux/phy.h +++ b/include/linux/phy.h @@ -485,6 +485,7 @@ void phy_driver_unregister(struct phy_driver *drv); int phy_driver_register(struct phy_driver *new_driver); void phy_prepare_link(struct phy_device *phydev, void (*adjust_link)(struct net_device *)); +void phy_state_machine(struct work_struct *work); void phy_start_machine(struct phy_device *phydev, void (*handler)(struct net_device *)); void phy_stop_machine(struct phy_device *phydev); -- cgit v1.2.3