[PATCH v2] igc: fix page fault when thunderbolt is unplugged

From: Aaron Ma
Date: Tue Jul 13 2021 - 09:07:36 EST


After unplug thunerbolt dock with i225, pciehp interrupt is triggered,
remove call will read/write mmio address which is already disconnected,
then cause page fault and make system hang.

Check PCI state to remove device safely.

Trace:
BUG: unable to handle page fault for address: 000000000000b604
Oops: 0000 [#1] SMP NOPTI
RIP: 0010:igc_rd32+0x1c/0x90 [igc]
Call Trace:
igc_ptp_suspend+0x6c/0xa0 [igc]
igc_ptp_stop+0x12/0x50 [igc]
igc_remove+0x7f/0x1c0 [igc]
pci_device_remove+0x3e/0xb0
__device_release_driver+0x181/0x240

Signed-off-by: Aaron Ma <aaron.ma@xxxxxxxxxxxxx>
---
drivers/net/ethernet/intel/igc/igc_main.c | 32 ++++++++++++++---------
drivers/net/ethernet/intel/igc/igc_ptp.c | 3 ++-
2 files changed, 21 insertions(+), 14 deletions(-)

diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c
index 95323095094d..3c72f135fc29 100644
--- a/drivers/net/ethernet/intel/igc/igc_main.c
+++ b/drivers/net/ethernet/intel/igc/igc_main.c
@@ -149,6 +149,9 @@ static void igc_release_hw_control(struct igc_adapter *adapter)
struct igc_hw *hw = &adapter->hw;
u32 ctrl_ext;

+ if (!pci_device_is_present(adapter->pdev))
+ return;
+
/* Let firmware take over control of h/w */
ctrl_ext = rd32(IGC_CTRL_EXT);
wr32(IGC_CTRL_EXT,
@@ -4447,26 +4450,29 @@ void igc_down(struct igc_adapter *adapter)

igc_ptp_suspend(adapter);

- /* disable receives in the hardware */
- rctl = rd32(IGC_RCTL);
- wr32(IGC_RCTL, rctl & ~IGC_RCTL_EN);
- /* flush and sleep below */
-
+ if (pci_device_is_present(adapter->pdev)) {
+ /* disable receives in the hardware */
+ rctl = rd32(IGC_RCTL);
+ wr32(IGC_RCTL, rctl & ~IGC_RCTL_EN);
+ /* flush and sleep below */
+ }
/* set trans_start so we don't get spurious watchdogs during reset */
netif_trans_update(netdev);

netif_carrier_off(netdev);
netif_tx_stop_all_queues(netdev);

- /* disable transmits in the hardware */
- tctl = rd32(IGC_TCTL);
- tctl &= ~IGC_TCTL_EN;
- wr32(IGC_TCTL, tctl);
- /* flush both disables and wait for them to finish */
- wrfl();
- usleep_range(10000, 20000);
+ if (pci_device_is_present(adapter->pdev)) {
+ /* disable transmits in the hardware */
+ tctl = rd32(IGC_TCTL);
+ tctl &= ~IGC_TCTL_EN;
+ wr32(IGC_TCTL, tctl);
+ /* flush both disables and wait for them to finish */
+ wrfl();
+ usleep_range(10000, 20000);

- igc_irq_disable(adapter);
+ igc_irq_disable(adapter);
+ }

adapter->flags &= ~IGC_FLAG_NEED_LINK_UPDATE;

diff --git a/drivers/net/ethernet/intel/igc/igc_ptp.c b/drivers/net/ethernet/intel/igc/igc_ptp.c
index 69617d2c1be2..4ae19c6a3247 100644
--- a/drivers/net/ethernet/intel/igc/igc_ptp.c
+++ b/drivers/net/ethernet/intel/igc/igc_ptp.c
@@ -849,7 +849,8 @@ void igc_ptp_suspend(struct igc_adapter *adapter)
adapter->ptp_tx_skb = NULL;
clear_bit_unlock(__IGC_PTP_TX_IN_PROGRESS, &adapter->state);

- igc_ptp_time_save(adapter);
+ if (pci_device_is_present(adapter->pdev))
+ igc_ptp_time_save(adapter);
}

/**
--
2.30.2