On Wed, Jan 06, 2021 at 11:53:59AM +0000, Mark Rutland wrote:

... and are you using defconfig or something else?

Not sure I replied to this. I'm not using the defconfig, I've my own
.config

As I mentioned, Will has built a 5.10 kernel using Arnd's gcc 4.9.4
and hasn't been able to reproduce it. He's sent me his kernel, which
I've booted here, and haven't yet been able to provoke it.

Meanwhile, my 5.9 kernel continues to exhibit this problem, so I've
sent Will my .config (which I'll include here.) There are differences
in some of the block layer configuration. There's differences in the
errata configuration, but we don't think that's a cause (they're not
relevant for Cortex A72).

Our plan is:
- Will is switching to 5.9, and using my config as a base for his
  platform.
- Will is going to send me his modified version of my config.
- We are both going to build using the same kernel sources and same
  config.
- We are going to test our own kernels, and also swap kernel images
  and test each others.

Watch this space for more news...

-- 
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