3.16.55-rc1 review patch. If anyone has any objections, please let me know.
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From: Christophe Leroy christophe.leroy@c-s.fr
commit f8b39039cbf2a15f2b8c9f081e1cbd5dee00aaf5 upstream.
In case of TX timeout, fs_timeout() calls phy_stop(), which triggers the following BUG_ON() as we are in interrupt.
[92708.199889] kernel BUG at drivers/net/phy/mdio_bus.c:482! [92708.204985] Oops: Exception in kernel mode, sig: 5 [#1] [92708.210119] PREEMPT [92708.212107] CMPC885 [92708.214216] CPU: 0 PID: 3 Comm: ksoftirqd/0 Tainted: G W 4.9.61 #39 [92708.223227] task: c60f0a40 task.stack: c6104000 [92708.227697] NIP: c02a84bc LR: c02a947c CTR: c02a93d8 [92708.232614] REGS: c6105c70 TRAP: 0700 Tainted: G W (4.9.61) [92708.241193] MSR: 00021032 <ME,IR,DR,RI>[92708.244818] CR: 24000822 XER: 20000000 [92708.248767] GPR00: c02a947c c6105d20 c60f0a40 c62b4c00 00000005 0000001f c069aad8 0001a688 GPR08: 00000007 00000100 c02a93d8 00000000 000005fc 00000000 c6213240 c06338e4 GPR16: 00000001 c06330d4 c0633094 00000000 c0680000 c6104000 c6104000 00000000 GPR24: 00000200 00000000 ffffffff 00000004 00000078 00009032 00000000 c62b4c00 NIP [c02a84bc] mdiobus_read+0x20/0x74 [92708.281517] LR [c02a947c] kszphy_config_intr+0xa4/0xc4 [92708.286547] Call Trace: [92708.288980] [c6105d20] [c6104000] 0xc6104000 (unreliable) [92708.294339] [c6105d40] [c02a947c] kszphy_config_intr+0xa4/0xc4 [92708.300098] [c6105d50] [c02a5330] phy_stop+0x60/0x9c [92708.305007] [c6105d60] [c02c84d0] fs_timeout+0xdc/0x110 [92708.310197] [c6105d80] [c035cd48] dev_watchdog+0x268/0x2a0 [92708.315593] [c6105db0] [c0060288] call_timer_fn+0x34/0x17c [92708.321014] [c6105dd0] [c00605f0] run_timer_softirq+0x21c/0x2e4 [92708.326887] [c6105e50] [c001e19c] __do_softirq+0xf4/0x2f4 [92708.332207] [c6105eb0] [c001e3c8] run_ksoftirqd+0x2c/0x40 [92708.337560] [c6105ec0] [c003b420] smpboot_thread_fn+0x1f0/0x258 [92708.343405] [c6105ef0] [c003745c] kthread+0xbc/0xd0 [92708.348217] [c6105f40] [c000c400] ret_from_kernel_thread+0x5c/0x64 [92708.354275] Instruction dump: [92708.357207] 7c0803a6 bbc10018 38210020 4e800020 7c0802a6 9421ffe0 54290024 bfc10018 [92708.364865] 90010024 7c7f1b78 81290008 552902ee <0f090000> 3bc3002c 7fc3f378 90810008 [92708.372711] ---[ end trace 42b05441616fafd7 ]---
This patch moves fs_timeout() actions into an async worker.
Fixes: commit 48257c4f168e5 ("Add fs_enet ethernet network driver, for several embedded platforms") Signed-off-by: Christophe Leroy christophe.leroy@c-s.fr Signed-off-by: David S. Miller davem@davemloft.net [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings ben@decadent.org.uk --- drivers/net/ethernet/freescale/fs_enet/fs_enet-main.c | 16 +++++++++++++--- drivers/net/ethernet/freescale/fs_enet/fs_enet.h | 1 + 2 files changed, 14 insertions(+), 3 deletions(-)
--- a/drivers/net/ethernet/freescale/fs_enet/fs_enet-main.c +++ b/drivers/net/ethernet/freescale/fs_enet/fs_enet-main.c @@ -696,9 +696,11 @@ static int fs_enet_start_xmit(struct sk_ return NETDEV_TX_OK; }
-static void fs_timeout(struct net_device *dev) +static void fs_timeout_work(struct work_struct *work) { - struct fs_enet_private *fep = netdev_priv(dev); + struct fs_enet_private *fep = container_of(work, struct fs_enet_private, + timeout_work); + struct net_device *dev = fep->ndev; unsigned long flags; int wake = 0;
@@ -710,7 +712,6 @@ static void fs_timeout(struct net_device phy_stop(fep->phydev); (*fep->ops->stop)(dev); (*fep->ops->restart)(dev); - phy_start(fep->phydev); }
phy_start(fep->phydev); @@ -721,6 +722,13 @@ static void fs_timeout(struct net_device netif_wake_queue(dev); }
+static void fs_timeout(struct net_device *dev) +{ + struct fs_enet_private *fep = netdev_priv(dev); + + schedule_work(&fep->timeout_work); +} + /*----------------------------------------------------------------------------- * generic link-change handler - should be sufficient for most cases *-----------------------------------------------------------------------------*/ @@ -847,6 +855,7 @@ static int fs_enet_close(struct net_devi netif_carrier_off(dev); if (fep->fpi->use_napi) napi_disable(&fep->napi); + cancel_work_sync(&fep->timeout_work); phy_stop(fep->phydev);
spin_lock_irqsave(&fep->lock, flags); @@ -1102,6 +1111,7 @@ static int fs_enet_probe(struct platform
ndev->netdev_ops = &fs_enet_netdev_ops; ndev->watchdog_timeo = 2 * HZ; + INIT_WORK(&fep->timeout_work, fs_timeout_work); if (fpi->use_napi) netif_napi_add(ndev, &fep->napi, fs_enet_rx_napi, fpi->napi_weight); --- a/drivers/net/ethernet/freescale/fs_enet/fs_enet.h +++ b/drivers/net/ethernet/freescale/fs_enet/fs_enet.h @@ -124,6 +124,7 @@ struct fs_enet_private { spinlock_t lock; /* during all ops except TX pckt processing */ spinlock_t tx_lock; /* during fs_start_xmit and fs_tx */ struct fs_platform_info *fpi; + struct work_struct timeout_work; const struct fs_ops *ops; int rx_ring, tx_ring; dma_addr_t ring_mem_addr;