> -----Original Message-----
> From: Intel-wired-lan <intel-wired-lan-bounces@xxxxxxxxxx> On Behalf Of Jesse Brandeburg
> Sent: Wednesday, October 4, 2023 10:32 PM
> To: intel-wired-lan@xxxxxxxxxxxxxxxx
> Cc: pmenzel@xxxxxxxxxxxxx; Vishal Agrawal <vagrawal@xxxxxxxxxx>; linux-pci@xxxxxxxxxxxxxxx; Brandeburg, Jesse <jesse.brandeburg@xxxxxxxxx>; netdev@xxxxxxxxxxxxxxx; jkc@xxxxxxxxxx; Kitszel, Przemyslaw <przemyslaw.kitszel@xxxxxxxxx>
> Subject: [Intel-wired-lan] [PATCH iwl-net v3] ice: reset first in crash dump kernels
>
> When the system boots into the crash dump kernel after a panic, the ice
> networking device may still have pending transactions that can cause errors
> or machine checks when the device is re-enabled. This can prevent the crash
> dump kernel from loading the driver or collecting the crash data.
>
> To avoid this issue, perform a function level reset (FLR) on the ice device
> via PCIe config space before enabling it on the crash kernel. This will
> clear any outstanding transactions and stop all queues and interrupts.
> Restore the config space after the FLR, otherwise it was found in testing
> that the driver wouldn't load successfully.
>
> The following sequence causes the original issue:
> - Load the ice driver with modprobe ice
> - Enable SR-IOV with 2 VFs: echo 2 > /sys/class/net/eth0/device/sriov_num_vfs
> - Trigger a crash with echo c > /proc/sysrq-trigger
> - Load the ice driver again (or let it load automatically) with modprobe ice
> - The system crashes again during pcim_enable_device()
>
> Fixes: 837f08fdecbe ("ice: Add basic driver framework for Intel(R) E800 Series")
>
> Reported-by: Vishal Agrawal <vagrawal@xxxxxxxxxx>
> Reviewed-by: Jay Vosburgh <jay.vosburgh@xxxxxxxxxxxxx>
> Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@xxxxxxxxx>
> Signed-off-by: Jesse Brandeburg <jesse.brandeburg@xxxxxxxxx>
> ---
> v3: add Fixes tag as approximate, added Jay's RB tag
> v2: respond to list comments and update commit message
> v1: initial version
> ---
> drivers/net/ethernet/intel/ice/ice_main.c | 15 +++++++++++++++
> 1 file changed, 15 insertions(+)
>
Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@xxxxxxxxx> (A Contingent worker at Intel)
