public inbox for linux-mm@kvack.org
 help / color / mirror / Atom feed
From: "David Hildenbrand (Arm)" <david@kernel.org>
To: Juan Yescas <jyescas@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>,
	Kalesh Singh <kaleshsingh@google.com>,
	"T.J. Mercier" <tjmercier@google.com>,
	Isaac Manjarres <isaacmanjarres@google.com>,
	android-mm <android-mm@google.com>,
	Linux Memory Management List <linux-mm@kvack.org>,
	Matthew Wilcox <willy@infradead.org>,
	Vlastimil Babka <vbabka@suse.cz>,
	Lorenzo Stoakes <lorenzo.stoakes@oracle.com>,
	lsf-pc@lists.linux-foundation.org
Subject: Re: [LSF/MM/BPF TOPIC] Discussion: Targeted memory allocation via debugfs
Date: Fri, 24 Apr 2026 14:34:22 +0200	[thread overview]
Message-ID: <60cd723d-82f0-410a-9a7b-c4d75a5c94e4@kernel.org> (raw)
In-Reply-To: <CAJDx_rjgyi-L-1j2kpi1NeKj+Huynd6ZFqJDmYqN8i8L3KyBfw@mail.gmail.com>

>> So maybe you really want a debug mechanism to migrate a (movable) user
>> space page into a CMA area?
>>
> One intent of this driver is to debug CMA issues (pinned MOVABLE pages). This
> The driver will allow easy reproduction of the case you just
> mentioned. For example,
> I will allocate most of the MOVABLE pages and then trigger a CMA
> allocation, that might trigger a migration.
> 
> However, the driver's main goal is to put the system into low-memory conditions.
> so we can reproduce OOO, kswad, lmkd issues seeing in the devices.

(Late reply ...)

But there are other ways to trigger low-memory conditions, no?

So I think the real missing piece you are looking for is getting a movable
userspace page allocated on CMA memory, to then try allocating from CMA to see
if migration works.

And you can do a bunch of things to make CMA's life has hard as possible.
O_DIRECT the userspace page, trigger low-memory conditions etc.

-- 
Cheers,

David


  reply	other threads:[~2026-04-24 12:34 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-02-27  2:42 [LSF/MM/BPF TOPIC] Discussion: Targeted memory allocation via debugfs Juan Yescas
2026-03-16 15:52 ` David Hildenbrand (Arm)
2026-03-19  0:56   ` Juan Yescas
2026-03-23  9:14     ` David Hildenbrand (Arm)
2026-04-08  0:12       ` Juan Yescas
2026-04-08  7:47         ` David Hildenbrand (Arm)
2026-04-08 21:32           ` Juan Yescas
2026-04-09  8:06             ` David Hildenbrand (Arm)
2026-04-09 15:57               ` Juan Yescas
2026-04-24 12:34                 ` David Hildenbrand (Arm) [this message]
2026-05-01  0:19                   ` Juan Yescas

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=60cd723d-82f0-410a-9a7b-c4d75a5c94e4@kernel.org \
    --to=david@kernel.org \
    --cc=android-mm@google.com \
    --cc=isaacmanjarres@google.com \
    --cc=jyescas@google.com \
    --cc=kaleshsingh@google.com \
    --cc=linux-mm@kvack.org \
    --cc=lorenzo.stoakes@oracle.com \
    --cc=lsf-pc@lists.linux-foundation.org \
    --cc=surenb@google.com \
    --cc=tjmercier@google.com \
    --cc=vbabka@suse.cz \
    --cc=willy@infradead.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox