RE: Regression v5.12-rc3: net: stmmac: re-init rx buffers when mac resume back

[Joakim Zhang]

> -----Original Message-----
> From: Jon Hunter <jonathanh@xxxxxxxxxx>
> Sent: 2021年3月24日 18:51
> To: Joakim Zhang <qiangqing.zhang@xxxxxxx>
> Cc: netdev@xxxxxxxxxxxxxxx; Linux Kernel Mailing List
> <linux-kernel@xxxxxxxxxxxxxxx>; linux-tegra <linux-tegra@xxxxxxxxxxxxxxx>;
> Jakub Kicinski <kuba@xxxxxxxxxx>
> Subject: Regression v5.12-rc3: net: stmmac: re-init rx buffers when mac
> resume back
> 
> Hi Joakim,
> 
> Starting with v5.12-rc3 I noticed that one of our boards, Tegra186 Jetson TX2,
> was not long resuming from suspend. Bisect points to commit 9c63faaa931e
> ("net: stmmac: re-init rx buffers when mac resume back") and reverting this on
> top of mainline fixes the problem.
> 
> Interestingly, the board appears to partially resume from suspend and I see
> ethernet appear to resume ...
> 
>  dwc-eth-dwmac 2490000.ethernet eth0: configuring for phy/rgmii link  mode
>  dwmac4: Master AXI performs any burst length  dwc-eth-dwmac
> 2490000.ethernet eth0: No Safety Features support found  dwc-eth-dwmac
> 2490000.ethernet eth0: Link is Up - 1Gbps/Full - flow  control rx/tx
> 
> I don't see any crash, but then it hangs at some point. Please note that this
> board is using NFS for mounting the rootfs.
> 
> Let me know if there is any more info I can provide or tests I can run.

Hi Jon,

Sorry for this breakage at your side.

You mean one of your boards? Does other boards with STMMAC can work fine?

We do daily test with NFS to mount rootfs, on issue found. And I add this patch at the resume patch, and on error check, this should not break suspend.
I even did the overnight stress test, there is no issue found.

Could you please do more test to see where the issue happen?

Best Regards,
Joakim Zhang
> Thanks
> Jon
>