From 7583605b6d29f1f7f6fc505b883328089f3485ad Mon Sep 17 00:00:00 2001 From: Anton Vorontsov Date: Thu, 24 Dec 2009 05:31:03 +0000 Subject: ucc_geth: Fix empty TX queue processing Following oops was seen with the ucc_geth driver: Unable to handle kernel paging request for data at address 0x00000058 Faulting instruction address: 0xc024f2fc Oops: Kernel access of bad area, sig: 11 [#1] [...] NIP [c024f2fc] skb_recycle_check+0x14/0x100 LR [e30aa0a4] ucc_geth_poll+0xd8/0x4e0 [ucc_geth_driver] Call Trace: [df857d50] [c000b03c] __ipipe_grab_irq+0x3c/0xa4 (unreliable) [df857d60] [e30aa0a4] ucc_geth_poll+0xd8/0x4e0 [ucc_geth_driver] [df857dd0] [c0258cf8] net_rx_action+0xf8/0x1b8 [df857e10] [c0032a38] __do_softirq+0xb8/0x13c [df857e60] [c00065cc] do_softirq+0xa0/0xac [...] This is because ucc_geth_tx() tries to process an empty queue when queues are logically stopped. Stopping the queues doesn't disable polling, and since nowadays ucc_geth_tx() is actually called from the polling routine, the oops above might pop up. Fix this by removing 'netif_queue_stopped() == 0' check. Reported-by: Lennart Sorensen Signed-off-by: Anton Vorontsov Tested-by: Lennart Sorensen Cc: Stable [2.6.32] Signed-off-by: David S. Miller --- drivers/net/ucc_geth.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/net/ucc_geth.c') diff --git a/drivers/net/ucc_geth.c b/drivers/net/ucc_geth.c index afaf088b72ea..0f8c99e845dd 100644 --- a/drivers/net/ucc_geth.c +++ b/drivers/net/ucc_geth.c @@ -3273,7 +3273,7 @@ static int ucc_geth_tx(struct net_device *dev, u8 txQ) /* Handle the transmitted buffer and release */ /* the BD to be used with the current frame */ - if ((bd == ugeth->txBd[txQ]) && (netif_queue_stopped(dev) == 0)) + if (bd == ugeth->txBd[txQ]) /* queue empty? */ break; dev->stats.tx_packets++; -- cgit v1.2.2 From 08b5e1c91ce95793c59a59529a362a1bcc81faae Mon Sep 17 00:00:00 2001 From: Anton Vorontsov Date: Thu, 24 Dec 2009 05:31:05 +0000 Subject: ucc_geth: Fix netdev watchdog triggering on link changes Since commit 864fdf884e82bacbe8ca5e93bd43393a61d2e2b4 ("ucc_geth: Fix hangs after switching from full to half duplex") ucc_geth driver disables the controller during MAC configuration changes. Though, disabling the controller might take quite awhile, and so the netdev watchdog might get upset: NETDEV WATCHDOG: eth2 (ucc_geth): transmit queue 0 timed out ------------[ cut here ]------------ Badness at c02729a8 [verbose debug info unavailable] NIP: c02729a8 LR: c02729a8 CTR: c01b6088 REGS: c0451c40 TRAP: 0700 Not tainted (2.6.32-trunk-8360e) [...] NIP [c02729a8] dev_watchdog+0x280/0x290 LR [c02729a8] dev_watchdog+0x280/0x290 Call Trace: [c0451cf0] [c02729a8] dev_watchdog+0x280/0x290 (unreliable) [c0451d50] [c00377c4] run_timer_softirq+0x164/0x224 [c0451da0] [c0032a38] __do_softirq+0xb8/0x13c [c0451df0] [c00065cc] do_softirq+0xa0/0xac [c0451e00] [c003280c] irq_exit+0x7c/0x9c [c0451e10] [c00640c4] __ipipe_sync_stage+0x248/0x24c [...] This patch fixes the issue by detaching the netdev during the time we change the configuration. Reported-by: Lennart Sorensen Signed-off-by: Anton Vorontsov Tested-by: Lennart Sorensen Cc: Stable [2.6.32] Signed-off-by: David S. Miller --- drivers/net/ucc_geth.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'drivers/net/ucc_geth.c') diff --git a/drivers/net/ucc_geth.c b/drivers/net/ucc_geth.c index 0f8c99e845dd..7fff4c5a1693 100644 --- a/drivers/net/ucc_geth.c +++ b/drivers/net/ucc_geth.c @@ -1563,7 +1563,10 @@ static int ugeth_disable(struct ucc_geth_private *ugeth, enum comm_dir mode) static void ugeth_quiesce(struct ucc_geth_private *ugeth) { - /* Wait for and prevent any further xmits. */ + /* Prevent any further xmits, plus detach the device. */ + netif_device_detach(ugeth->ndev); + + /* Wait for any current xmits to finish. */ netif_tx_disable(ugeth->ndev); /* Disable the interrupt to avoid NAPI rescheduling. */ @@ -1577,7 +1580,7 @@ static void ugeth_activate(struct ucc_geth_private *ugeth) { napi_enable(&ugeth->napi); enable_irq(ugeth->ug_info->uf_info.irq); - netif_tx_wake_all_queues(ugeth->ndev); + netif_device_attach(ugeth->ndev); } /* Called every time the controller might need to be made -- cgit v1.2.2 From 08fafd8461c0ca8d1b389b7dc11d17e7b2331282 Mon Sep 17 00:00:00 2001 From: Anton Vorontsov Date: Thu, 24 Dec 2009 05:31:20 +0000 Subject: ucc_geth: Don't needlessly change MAC settings in adjust_link() If PHY doesn't have an IRQ, phylib would poll for link changes, and would call adjust_link() every second. In that case we disable and enable the controller every second. Let's better check if there is actually anything changed, and, if so, change the MAC settings. Signed-off-by: Anton Vorontsov Signed-off-by: David S. Miller --- drivers/net/ucc_geth.c | 33 ++++++++++++++++++--------------- 1 file changed, 18 insertions(+), 15 deletions(-) (limited to 'drivers/net/ucc_geth.c') diff --git a/drivers/net/ucc_geth.c b/drivers/net/ucc_geth.c index 7fff4c5a1693..41ad2f3697c7 100644 --- a/drivers/net/ucc_geth.c +++ b/drivers/net/ucc_geth.c @@ -1651,25 +1651,28 @@ static void adjust_link(struct net_device *dev) ugeth->oldspeed = phydev->speed; } - /* - * To change the MAC configuration we need to disable the - * controller. To do so, we have to either grab ugeth->lock, - * which is a bad idea since 'graceful stop' commands might - * take quite a while, or we can quiesce driver's activity. - */ - ugeth_quiesce(ugeth); - ugeth_disable(ugeth, COMM_DIR_RX_AND_TX); - - out_be32(&ug_regs->maccfg2, tempval); - out_be32(&uf_regs->upsmr, upsmr); - - ugeth_enable(ugeth, COMM_DIR_RX_AND_TX); - ugeth_activate(ugeth); - if (!ugeth->oldlink) { new_state = 1; ugeth->oldlink = 1; } + + if (new_state) { + /* + * To change the MAC configuration we need to disable + * the controller. To do so, we have to either grab + * ugeth->lock, which is a bad idea since 'graceful + * stop' commands might take quite a while, or we can + * quiesce driver's activity. + */ + ugeth_quiesce(ugeth); + ugeth_disable(ugeth, COMM_DIR_RX_AND_TX); + + out_be32(&ug_regs->maccfg2, tempval); + out_be32(&uf_regs->upsmr, upsmr); + + ugeth_enable(ugeth, COMM_DIR_RX_AND_TX); + ugeth_activate(ugeth); + } } else if (ugeth->oldlink) { new_state = 1; ugeth->oldlink = 0; -- cgit v1.2.2