Re: [PATCH] selftests/mm: remove virtual_address_range test

[Lorenzo Stoakes <lorenzo.stoakes@oracle.com>]

On Mon, Jan 19, 2026 at 11:39:51AM +0100, David Hildenbrand (Red Hat) wrote:
> On
>
> $ uname -r
> 6.18.4-200.fc43.x86_64
>
> I am getting
>
> $ ./va_high_addr_switch
> mmap(addr_switch_hint - pagesize, pagesize): 0x7fe7de6d7000 - OK
> mmap(addr_switch_hint - pagesize, (2 * pagesize)): 0x7fe7de6d6000 - OK
> mmap(addr_switch_hint, pagesize): 0x7fe7de6d7000 - OK
> mmap(addr_switch_hint, 2 * pagesize, MAP_FIXED): 0xffffffffffffffff - FAILED
> mmap(NULL): 0x7fe7de6d5000 - OK
> mmap(low_addr): 0x40000000 - OK
> mmap(high_addr): 0x7fe7de6d5000 - OK
> mmap(high_addr) again: 0x7fe7de6d3000 - OK
> mmap(high_addr, MAP_FIXED): 0xffffffffffffffff - FAILED
> mmap(-1): 0x7fe7de6d1000 - OK
> mmap(-1) again: 0x7fe7de6cf000 - OK
> mmap(addr_switch_hint - pagesize, pagesize): 0x7fe7de6d0000 - OK
> mmap(addr_switch_hint - pagesize, 2 * pagesize): 0x7fe7de6cf000 - OK
> mmap(addr_switch_hint - pagesize/2 , 2 * pagesize): 0x7fe7de6cd000 - OK
> mmap(addr_switch_hint, pagesize): 0x7fe7de6cc000 - OK
> mmap(addr_switch_hint, 2 * pagesize, MAP_FIXED): 0xffffffffffffffff - FAILED
>
>
> Are these the same issues you see?

No, that's entirely separate bug it seems :)

Seems to work locally for me on 6.18.3, and also in VM with tip mm-unstable,
strange.

The issue here is with virtual_address_space.c which seems to just to be
generally broken, I couldn't even bisect to a working one, and I really did
try.

Actually hang on, isn't va_high_addr_space already then testing what
virtual_address_space should be testing anyway if it were sensible??

That suggests then that just removing virtual_address_space without
replacement (since this already exists) is the right way (...!)

Thanks, Lorenzo