On Sun, Jan 03, 2021 at 05:26:29PM +0100, Arnd Bergmann wrote:

Thank you for the report and bisecting the issue, and sorry this broke
your system!

Fortunately, the patch is fairly small, so there are only a limited number
of things that could go wrong. I haven't tried to analyze that message,
but I have two ideas:

a) The added ioc->sense_off check gets triggered and the code relies
  on the data being written outside of the structure

b) the address actually needs to always be written as a 64-bit value
    regardless of the instance->consistent_mask_64bit flag, as the
   driver did before. This looked like it was done in error.

Can you try the patch below instead of the revert and see if that
resolves the regression, and if it triggers the warning message I
add?

Thanks Arnd, I tried your patch and it resolves the regression.  It does not
trigger the warning message you added.

Phil