Re: ce56a86e2a ("x86/mm: Limit mmap() of /dev/mem to valid physical addresses"): kernel BUG at arch/x86/mm/physaddr.c:79!

[Ingo Molnar]

* Craig Bergstrom <craigb@xxxxxxxxxx> wrote:

> Sander, thanks for the details, they've been very useful.
> 
> I suspect that your host system's mem=2048M parameter is causing the
> problem.  Any chance you can confirm by removing the parameter and
> running the guest code path?
> 
> More specifically, since you're telling the kernel that it's high
> memory address is at 2048M and your device is at 0xfe1fe000 (~4G), the
> new mmap() limits are preventing you from mapping addresses that are
> explicitly disallowed by the parameter.

Well, 'mem=2048M' shouldn't really limit device memory, it's supposed to limit 
(trim) 'RAM' and not much else.

Thanks,

	Ingo