Blank screen with 460.27.04

On my Gentoo Laptop, Kernel 5.9.11, GeForce GTX 880M with internal display attached via eDP, after upgrading from 455.45.01 to 460.27.04, the screen switches to black during load of the nvidia modules, then turns the backlight on and off several times, and finally stays off.
VT switching does not work at this point, the system is still accessible via SSH.
Downgrading to 455.45.01 (with no other changes to the system) fixes the issue.

The kernel log contains the following lines of interest:

Jan  5 15:09:45 localhost kernel: [   33.746156] nvidia-modeset: ERROR: GPU:0: Display engine push buffer channel allocation failed: 0x65 (Call timed out [NV_ERR_TIMEOUT])
Jan  5 15:09:45 localhost kernel: [   33.746935] nvidia-modeset: ERROR: GPU:0: Failed to allocate display engine core DMA push buffer

Full nvidia-bug-report attached. Note I needed to kill vulkaninfo, which got stuck during data collection, for nvidia-bug-report to finish.
nvidia-bug-report.log.gz (1.2 MB)

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