From e72319bba814b115c47785b3b88f7263d0b8a1b8 Mon Sep 17 00:00:00 2001 From: Jacob Keller Date: Thu, 4 Feb 2016 10:47:55 -0800 Subject: [PATCH] fm10k: don't initialize service task until later in probe Delay initialization of the service timer and service task until late probe. If we don't wait, failures in probe do not properly cleanup the service timer or service task items, which results in the kernel panic below, potentially freezing the whole system. In addition, ensure that the SERVICE_DISABLE bit is set before we request the MBX IRQ since the MBX interrupt attempts to schedule the service task otherwise. This prevents a similar trace from occurring after this change. We didn't notice this issue before because probe almost always completes successfully. I discovered it due to a mis-ordered mailbox handler array, which resulted in the following failure when requesting mailbox interrupt. [ 555.325619] ------------[ cut here ]------------ [ 555.325628] WARNING: CPU: 0 PID: 4941 at lib/list_debug.c:33 __list_add+0xa0/0xd0() [ 555.325631] list_add corruption. prev->next should be next (ffffffff81f46648), but was (null). (prev=ffff8807fad5d0e8). [ 555.325722] CPU: 0 PID: 4941 Comm: insmod Tainted: G OE 4.0.4-303.fc22.x86_64 #1 [ 555.325725] Hardware name: Intel Corporation S2600CO/S2600CO, BIOS SE5C600.86B.02.03.8x23.060520140825 06/05/2014 [ 555.325727] 0000000000000000 00000000b4f161b3 ffff88081a21f8e8 ffffffff81783124 [ 555.325734] 0000000000000000 ffff88081a21f940 ffff88081a21f928 ffffffff8109c66a [ 555.325740] 0000000064000000 ffff8807fad5d0e8 ffff8807fad5d0e8 ffffffff81f46648 [ 555.325746] Call Trace: [ 555.325752] [] dump_stack+0x45/0x57 [ 555.325757] [] warn_slowpath_common+0x8a/0xc0 [ 555.325759] [] warn_slowpath_fmt+0x55/0x70 [ 555.325763] [] __list_add+0xa0/0xd0 [ 555.325768] [] __internal_add_timer+0x9d/0x110 [ 555.325771] [] internal_add_timer+0x2f/0xc0 [ 555.325774] [] mod_timer+0x12a/0x230 [ 555.325782] [] fm10k_probe+0x69a/0xc80 [fm10k] [ 555.325787] [] local_pci_probe+0x45/0xa0 [ 555.325791] [] ? sysfs_do_create_link_sd.isra.2+0x72/0xc0 [ 555.325794] [] pci_device_probe+0xf9/0x150 [ 555.325799] [] driver_probe_device+0xa3/0x400 [ 555.325802] [] __driver_attach+0x9b/0xa0 [ 555.325805] [] ? __device_attach+0x40/0x40 [ 555.325808] [] bus_for_each_dev+0x73/0xc0 [ 555.325811] [] driver_attach+0x1e/0x20 [ 555.325815] [] bus_add_driver+0x180/0x250 [ 555.325819] [] ? 0xffffffffa03b2000 [ 555.325823] [] driver_register+0x64/0xf0 [ 555.325826] [] __pci_register_driver+0x4c/0x50 [ 555.325832] [] fm10k_register_pci_driver+0x23/0x30 [fm10k] [ 555.325838] [] fm10k_init_module+0x80/0x1000 [fm10k] [ 555.325843] [] do_one_initcall+0xb8/0x200 [ 555.325848] [] ? __vunmap+0xa2/0x100 [ 555.325852] [] ? kmem_cache_alloc_trace+0x1b9/0x240 [ 555.325855] [] ? do_init_module+0x28/0x1cb [ 555.325858] [] do_init_module+0x60/0x1cb [ 555.325862] [] load_module+0x205e/0x26b0 [ 555.325866] [] ? store_uevent+0x70/0x70 [ 555.325870] [] ? kernel_read+0x50/0x80 [ 555.325873] [] SyS_finit_module+0xbe/0xf0 [ 555.325878] [] system_call_fastpath+0x12/0x17 [ 555.325880] ---[ end trace 9e0f58d071eafd2a ]--- Signed-off-by: Jacob Keller Tested-by: Krishneil Singh Signed-off-by: Jeff Kirsher --- drivers/net/ethernet/intel/fm10k/fm10k_pci.c | 25 +++++++++++++------- 1 file changed, 16 insertions(+), 9 deletions(-) diff --git a/drivers/net/ethernet/intel/fm10k/fm10k_pci.c b/drivers/net/ethernet/intel/fm10k/fm10k_pci.c index 8c23fb3df572..ed1f8cf39508 100644 --- a/drivers/net/ethernet/intel/fm10k/fm10k_pci.c +++ b/drivers/net/ethernet/intel/fm10k/fm10k_pci.c @@ -1795,15 +1795,6 @@ static int fm10k_sw_init(struct fm10k_intfc *interface, /* initialize DCBNL interface */ fm10k_dcbnl_set_ops(netdev); - /* Initialize service timer and service task */ - set_bit(__FM10K_SERVICE_DISABLE, &interface->state); - setup_timer(&interface->service_timer, &fm10k_service_timer, - (unsigned long)interface); - INIT_WORK(&interface->service_task, fm10k_service_task); - - /* kick off service timer now, even when interface is down */ - mod_timer(&interface->service_timer, (HZ * 2) + jiffies); - /* Intitialize timestamp data */ fm10k_ts_init(interface); @@ -1989,6 +1980,12 @@ static int fm10k_probe(struct pci_dev *pdev, const struct pci_device_id *ent) if (err) goto err_sw_init; + /* the mbx interrupt might attempt to schedule the service task, so we + * must ensure it is disabled since we haven't yet requested the timer + * or work item. + */ + set_bit(__FM10K_SERVICE_DISABLE, &interface->state); + err = fm10k_mbx_request_irq(interface); if (err) goto err_mbx_interrupt; @@ -2008,6 +2005,16 @@ static int fm10k_probe(struct pci_dev *pdev, const struct pci_device_id *ent) /* stop all the transmit queues from transmitting until link is up */ netif_tx_stop_all_queues(netdev); + /* Initialize service timer and service task late in order to avoid + * cleanup issues. + */ + setup_timer(&interface->service_timer, &fm10k_service_timer, + (unsigned long)interface); + INIT_WORK(&interface->service_task, fm10k_service_task); + + /* kick off service timer now, even when interface is down */ + mod_timer(&interface->service_timer, (HZ * 2) + jiffies); + /* Register PTP interface */ fm10k_ptp_register(interface); -- 2.20.1