I've been using grsec for quite a long time now. Recently I've began upgrading all of my servers from 2.4.20, grsec-1.9.9e to 2.4.21, grsec-1.9.11. The upgrade was fine for most computers except for a few. Grsecurity is set to 'medium'.
Minor issue was that 'ide' modules would fail during modprobe, although if i were to compile ide modules within kernel then they work.
The major issue is highmem support. When I enable 'highmem' support in kernel and when computer starts up all the modules fail during modprobe. The same thing happens when I enable SMP support in kernel. I am pretty sure this is a grsec issue because when I compile unpatched kernel then it works. With grsec kernel even if i disable everything, the 'highmem' and SMP support just break all the modules.
This is a new issue, and I never had anything like this with previous kernels/grsec versions.
I would appreciate if any of the developers respond to this, because of this issue I am unable to upgrade my most critical servers.
Thank You,
Walter.