Hi Pawel,
Am 13.02.2019 um 17:45 schrieb Paweł Chmiel pawel.mikolaj.chmiel@gmail.com:
So I have to check what did break in between. And when. Most likely something with memory allocation.
For mainline You will probably need https://github.com/PabloPL/linux/commit/de0f7e299d94f5dfdcf15375ec2d3ace54ac... because powervr is using some strange pointers.
Yes, thats it!
I found a backported version of be83bbf ("mmap: introduce sane default mmap limits") appear in v4.16.14 -> v4.16.15 as the only patch that did modify mm/mmap.c
Either reverting that or applying your recommended one fixes the issue for all kernels starting with 4.16.15 or 4.17-rc5 up to 5.0-rc6.
IMHO this is the first example where this collaboration of our group is already very helpful because we start to exchange knowledge about common problems.
For this patch, the key question is what a better solution will be. Most likely reworking the "pgoff << PAGE_SHIFT" stuff from which I remember that it is used quite a lot. But that should be done once for all and everybody on our future master branch.
So I now have back an (almost) working reference system on v5.0-rc6 for GTA04, BeagleBoard, BeagleBone, PocketBeagle and potentially OpenPanodra (which uses the omap3430/sgx121 variant).
At least I can download and start firmware. I just have to find a way to fix the omaplfb so that it works with our omapdrm based panels to runs the CLipBlit test [1] on modern kernels...
BR and thanks, Nikolaus