Re: AMD GPU driver load hitting BUG_ON in sync_global_pgds_l5()

[Bharata B Rao <bharata@amd.com>]

On 22-Apr-25 12:44 PM, Balbir Singh wrote:
> On 4/22/25 16:34, Bharata B Rao wrote:
> 
> Could you please confirm if this is a new issue? Sounds like your hitting it on 6.8.12+?
> I've never tested this on a system with 5 levels of page tables, but with 5 levels you get
> 52 bits of VA and you'll need to look at the KASLR logic (max_pfn + padding) to see where
> your ranges are getting assigned.
> 
> I'd start by dumping the kaslr_regions array.

Here is how the ranges look like for the upstream kernel for two boots:

Iteration 1:
kaslr_region: base[0] ff4552df80000000 size_tb 1000
kaslr_region: end[0] fffffffffffff
kaslr_region: base[1] ff69c69640000000 size_tb 3200
kaslr_region: base[2] ffd3140680000000 size_tb 40

Iteration 2:
kaslr_region: base[0] ff3a9c84c0000000 size_tb 1000
kaslr_region: end[0] fffffffffffff
kaslr_region: base[1] ff73d27480000000 size_tb 3200
kaslr_region: base[2] fff01edb40000000 size_tb 40

Regards,
Bharata.