[Bug Report] [6.6] i2c: No atomic i2c transfer handler

[Tor Vic]

Hi,

Since Linux 6.6.3, I see some warnings in the late phase of shutdown.
Unfortunately, they are not logged because syslog has already shut down 
at that point.

I used a camera to capture a small part of the warnings:

  No atomic I2C transfer handler for 'i2c-0'
  [trace follows]
  i2c_smbus_xfer
  [...]

After checking the changelog, the culprit was found quickly:

  (3473cf43b) i2c: core: Run atomic i2c xfer when !preemptible

Reverting that commit made the warnings go away.

This is a voluntary preemption kernel running on a Skylake laptop.

Please tell me if you need more info.

Cheers,
Tor