Bug#1091732: linux-image-6.11.10+bpo-amd64: Kernel fail to setup video correctly on server Dell PowerEdge R660

[Salvatore Bonaccorso <carnil@debian.org>]

Control: tags -1 + moreinfo

Hi Jose,

On Mon, Dec 30, 2024 at 03:53:03PM +0000, Jose M Calhariz wrote:
> Package: src:linux
> Version: 6.11.10-1~bpo12+1
> Severity: normal
> 
> I found that this kernel fails to setup the video mode of the display
> adapter, where a kernel 6.1 seams to work, on a server Dell PowerEdge
> R660.  The work around is to use mgag200.modeset=0.  This machine is
> to be used as a server, no graphics, X11 or Wayland, just text console
> after a boot from UEFI.  But I need iDRAC, BMC from dell or IPMI, to
> sucessfully export the console of the machine to be managed when SSH
> fails.
> 
> I am open to do more tests or give more information as I understand an
> R660 may not be available to the Debian Kernel Team.

Is this something you still can reproduce with current kernels, so
6.12.43-1~bpo12+1?

Can you easily take out the server for maintenance, and so do further
experiments, assuming you can reproduce it with 6.12.43 based kernel,
does 6.16.7-1 as well still expose the problem?

If yes: Can you bisect the changes between 6.1 upstream and 6.11
upstream to identify the commit which changes things for you? (do you
need instructions on how to proceed on bisection?).

Regards,
Salvatore