From a15f78ea1171d5c901a804558aedbbde07ca2dea Mon Sep 17 00:00:00 2001 From: Stefan Assmann Date: Fri, 5 Mar 2021 13:38:56 +0100 Subject: [PATCH] iavf: do not override the adapter state in the watchdog task The iavf watchdog task overrides adapter->state to __IAVF_RESETTING when it detects a pending reset. Then schedules iavf_reset_task() which takes care of the reset. The reset task is capable of handling the reset without changing adapter->state. In fact we lose the state information when the watchdog task prematurely changes the adapter state. This may lead to a crash if instead of the reset task the iavf_remove() function gets called before the reset task. In that case (if we were in state __IAVF_RUNNING previously) the iavf_remove() function triggers iavf_close() which fails to close the device because of the incorrect state information. This may result in a crash due to pending interrupts. kernel BUG at drivers/pci/msi.c:357! [...] Call Trace: [] pci_disable_msix+0x3d/0x50 [] iavf_reset_interrupt_capability+0x23/0x40 [iavf] [] iavf_remove+0x10a/0x350 [iavf] [] pci_device_remove+0x39/0xc0 [] __device_release_driver+0x7f/0xf0 [] device_release_driver+0x23/0x30 [] pci_stop_bus_device+0x84/0xa0 [] pci_stop_and_remove_bus_device+0x12/0x20 [] pci_iov_remove_virtfn+0xaf/0x160 [] sriov_disable+0x3c/0xf0 [] pci_disable_sriov+0x23/0x30 [] i40e_free_vfs+0x265/0x2d0 [i40e] [] i40e_pci_sriov_configure+0x144/0x1f0 [i40e] [] sriov_numvfs_store+0x177/0x1d0 Code: 00 00 e8 3c 25 e3 ff 49 c7 86 88 08 00 00 00 00 00 00 5b 41 5c 41 5d 41 5e 41 5f 5d c3 48 8b 7b 28 e8 0d 44 RIP [] free_msi_irqs+0x188/0x190 The solution is to not touch the adapter->state in iavf_watchdog_task() and let the reset task handle the state transition. Signed-off-by: Stefan Assmann Tested-by: Konrad Jankowski Signed-off-by: Tony Nguyen --- drivers/net/ethernet/intel/iavf/iavf_main.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/net/ethernet/intel/iavf/iavf_main.c b/drivers/net/ethernet/intel/iavf/iavf_main.c index 44bafedd09f28..44cadf4ebb24f 100644 --- a/drivers/net/ethernet/intel/iavf/iavf_main.c +++ b/drivers/net/ethernet/intel/iavf/iavf_main.c @@ -1988,7 +1988,6 @@ static void iavf_watchdog_task(struct work_struct *work) /* check for hw reset */ reg_val = rd32(hw, IAVF_VF_ARQLEN1) & IAVF_VF_ARQLEN1_ARQENABLE_MASK; if (!reg_val) { - adapter->state = __IAVF_RESETTING; adapter->flags |= IAVF_FLAG_RESET_PENDING; adapter->aq_required = 0; adapter->current_op = VIRTCHNL_OP_UNKNOWN; -- 2.39.5