ACK: [PATCH 1/1] UBUNTU: SAUCE: igc: fix page fault when thunderbolt is unplugged

[Kleber Souza]

On 02.08.21 12:56, Aaron Ma wrote:
> BugLink: https://bugs.launchpad.net/bugs/1938689
> 
> After unplug thunderbolt 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 at canonical.com>
> (cherry picked from commit 25475b830989e2879bd0fd60d7a14a1db0df8f5c
> https://git.kernel.org/pub/scm/linux/kernel/git/tnguy/next-queue.git
> branch dev-queue)
> Signed-off-by: Aaron Ma <aaron.ma at canonical.com>

Acked-by: Kleber Sacilotto de Souza <kleber.souza at canonical.com>

Thanks

> ---
>   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 f1adf154ec4a..49ba039f66db 100644
> --- a/drivers/net/ethernet/intel/igc/igc_main.c
> +++ b/drivers/net/ethernet/intel/igc/igc_main.c
> @@ -146,6 +146,9 @@ 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,
> @@ -4035,26 +4038,29 @@ 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);
>   }
>   
>   /**
>