linux-kernel - Re: [PATCH v2 2/7] selftests/mm: Add support to test 4PB VA on PPC64

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <fa2da701-d2ba-4a27-9d9c-c8e1434edb9b@arm.com>
Date: Thu, 3 Jul 2025 13:35:30 +0530
From: Dev Jain <dev.jain@....com>
To: Aboorva Devarajan <aboorvad@...ux.ibm.com>, akpm@...ux-foundation.org,
 Liam.Howlett@...cle.com, lorenzo.stoakes@...cle.com, shuah@...nel.org,
 pfalcato@...e.de, david@...hat.com, ziy@...dia.com,
 baolin.wang@...ux.alibaba.com, npache@...hat.com, ryan.roberts@....com,
 baohua@...nel.org
Cc: linux-mm@...ck.org, linux-kselftest@...r.kernel.org,
 linux-kernel@...r.kernel.org, donettom@...ux.ibm.com, ritesh.list@...il.com
Subject: Re: [PATCH v2 2/7] selftests/mm: Add support to test 4PB VA on PPC64


On 03/07/25 11:36 am, Aboorva Devarajan wrote:
> From: Donet Tom <donettom@...ux.ibm.com>
>
> PowerPC64 supports a 4PB virtual address space, but this test was
> previously limited to 512TB. This patch extends the coverage up to
> the full 4PB VA range on PowerPC64.
>
> Memory from 0 to 128TB is allocated without an address hint, while
> allocations from 128TB to 4PB use a hint address.
>
> Signed-off-by: Donet Tom <donettom@...ux.ibm.com>
> Signed-off-by: Aboorva Devarajan <aboorvad@...ux.ibm.com>
> ---

Would have saved us a lot of time if we had figured out that
the problem wasn't the gap logic but the large VA space support,
anyhow digging down that rabbit hole gave me some knowledge
on VMA allocation stuff : )

Reviewed-by: Dev Jain <dev.jain@....com>