I just tested again on 5.3.0-43 since I thought I remember having seen the issue there too.
It does have the problem:
May 7 09:03:25 x1 kernel: [ 0.000000] Linux version 5.3.0-43-generic (buildd@lcy01-amd64-024) (gcc version 7.5.0 (Ubuntu 7.5.0-3ubuntu1~18.04)) #36~18.04.2-Ubuntu SMP Thu Mar 19 16:03:35 UTC 2020 (Ubuntu 5.3.0-43.36~18.04.2-generic 5.3.18)
May 7 09:04:27 x1 kernel: [ 69.099086] i915 0000:00:02.0: GPU HANG: ecode 9:0:0x00000000, hang on rcs0
May 7 09:04:27 x1 kernel: [ 69.100094] i915 0000:00:02.0: Resetting rcs0 for hang on rcs0
(I've gone back to 4.15 to avoid this problem and the docker issue mentioned above)
Another datapoint:
I just tested again on 5.3.0-43 since I thought I remember having seen the issue there too.
It does have the problem:
May 7 09:03:25 x1 kernel: [ 0.000000] Linux version 5.3.0-43-generic (buildd@ lcy01-amd64- 024) (gcc version 7.5.0 (Ubuntu 7.5.0-3ubuntu1~ 18.04)) #36~18.04.2-Ubuntu SMP Thu Mar 19 16:03:35 UTC 2020 (Ubuntu 5.3.0-43. 36~18.04. 2-generic 5.3.18)
May 7 09:04:27 x1 kernel: [ 69.099086] i915 0000:00:02.0: GPU HANG: ecode 9:0:0x00000000, hang on rcs0
May 7 09:04:27 x1 kernel: [ 69.100094] i915 0000:00:02.0: Resetting rcs0 for hang on rcs0
(I've gone back to 4.15 to avoid this problem and the docker issue mentioned above)