[Intel-wired-lan] suspend/resume broken of igc driver broken on 6.12

[Lifshits, Vitaly]

On 1/31/2025 3:21 AM, Stephen Hemminger wrote:
> On Thu, 30 Jan 2025 21:17:30 +0200
> "Lifshits, Vitaly" <vitaly.lifshits at intel.com> wrote:
> 
>> On 1/30/2025 7:11 PM, Stephen Hemminger wrote:
>>> I am using:
>>>
>>> 5a:00.0 Ethernet controller: Intel Corporation Ethernet Controller I226-LM (rev 04)
>>> 	Subsystem: Intel Corporation Device 0000
>>> 	Flags: bus master, fast devsel, latency 0, IRQ 19, IOMMU group 20
>>> 	Memory at 6c500000 (32-bit, non-prefetchable) [size=1M]
>>> 	Memory at 6c600000 (32-bit, non-prefetchable) [size=16K]
>>> 	Capabilities: [40] Power Management version 3
>>> 	Capabilities: [50] MSI: Enable- Count=1/1 Maskable+ 64bit+
>>> 	Capabilities: [70] MSI-X: Enable+ Count=5 Masked-
>>> 	Capabilities: [a0] Express Endpoint, IntMsgNum 0
>>> 	Capabilities: [100] Advanced Error Reporting
>>> 	Capabilities: [140] Device Serial Number 58-47-ca-ff-ff-7a-98-3d
>>> 	Capabilities: [1c0] Latency Tolerance Reporting
>>> 	Capabilities: [1f0] Precision Time Measurement
>>> 	Capabilities: [1e0] L1 PM Substates
>>> 	Kernel driver in use: igc
>>> 	Kernel modules: igc
>>>
>>>
>>> Using both Debian testing and my own kernel built from 6.12, the igc
>>> driver appears broken after resume.
>>
>>   From which system state are you resuming?
>>
>>>
>>> After resuming the device is down and no address present.
>>> Attempts to set link up manually fail.
>>
>> Did you get any errors in the dmesg log?
>> What is the firmware version on your device (you can get it by running
>> ethtool -i)?
>>
>>> If I do rmmod/modprobe of igc it comes back.
>>>
>>> Doing a bit of bisectting but it is slow going.
>>
>> Meanwhile, we'll also try to reproduce this issue in our lab.  Could you
>> share more details about your system so we can create a similar setup?
> 
> Given that error reported is -ENODEV, might be a generic netdev problem not
> just for igc device.
> 

We weren't able to reproduce this issue on our systems, even though we 
tried several suspend-resume cycles on different kernels and different 
systems.

However, a few days ago we received a comment in a BZ about an issue 
similar to yours. In there adding a short delay in igc_resume function
https://bugzilla.kernel.org/show_bug.cgi?id=219143
https://bugzilla.kernel.org/show_bug.cgi?id=219143#c123



Can you try to see if it fixes your issue as well?