Linux-mm Archive on lore.kernel.org
 help / color / mirror / Atom feed
From: Kiryl Shutsemau <kas@kernel.org>
To: "Mike Rapoport (Microsoft)" <rppt@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>,
	 David Hildenbrand <david@kernel.org>,
	"Liam R. Howlett" <liam@infradead.org>,
	 Lorenzo Stoakes <ljs@kernel.org>, Michal Hocko <mhocko@suse.com>,
	 Suren Baghdasaryan <surenb@google.com>,
	Vlastimil Babka <vbabka@kernel.org>,
	 linux-kernel@vger.kernel.org, linux-mm@kvack.org,
	stable@vger.kernel.org
Subject: Re: [PATCH 0/2] mm/cma: accept memory of CMA areas reserved with memblock_reserve()
Date: Thu, 29 Oct 2026 12:27:23 +0000	[thread overview]
Message-ID: <auM6lKGAeUI26jCj@thinkstation> (raw)
In-Reply-To: <20261029-cma-multi-v1-0-2cbced8b5cb7@kernel.org>

On Thu, Oct 29, 2026 at 12:18:36PM +0200, Mike Rapoport (Microsoft) wrote:
> Pages of allocated CMA areas are released to the buddy allocator with
> __free_pages(), which does not check for unaccepted memory.
> 
> This usually works because memblock accepts the memory it allocates.
> 
> However, multi-range CMA areas, used by hugetlb_cma, and fixed CMA areas
> requested with cma=<size>@<base> are reserved with memblock_reserve() and
> their memory is never accepted.

It feels like memblock_reserve() abuse, no?

crashkernel=size@base already uses memblock_phys_alloc_range() for this.
Should the fixed and multi-range CMA paths go through the allocation API
as well.

-- 
  Kiryl Shutsemau / Kirill A. Shutemov


  parent reply	other threads:[~2026-10-29 12:27 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-10-29 10:18 [PATCH 0/2] mm/cma: accept memory of CMA areas reserved with memblock_reserve() Mike Rapoport (Microsoft)
2026-10-29 10:18 ` [PATCH 1/2] mm/cma: accept memory of multi-range CMA areas Mike Rapoport (Microsoft)
2026-10-29 10:52   ` Gupta, Pankaj
2026-10-29 12:19     ` Mike Rapoport
2026-10-29 10:18 ` [PATCH 2/2] mm/cma: accept memory of CMA areas reserved at a fixed address Mike Rapoport (Microsoft)
2026-10-29 12:27 ` Kiryl Shutsemau [this message]
2026-10-29 12:40   ` [PATCH 0/2] mm/cma: accept memory of CMA areas reserved with memblock_reserve() Mike Rapoport
2026-10-29 13:17     ` Kiryl Shutsemau
2026-10-29 15:03       ` Mike Rapoport
2026-10-29 15:39         ` Kiryl Shutsemau

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=auM6lKGAeUI26jCj@thinkstation \
    --to=kas@kernel.org \
    --cc=akpm@linux-foundation.org \
    --cc=david@kernel.org \
    --cc=liam@infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=ljs@kernel.org \
    --cc=mhocko@suse.com \
    --cc=rppt@kernel.org \
    --cc=stable@vger.kernel.org \
    --cc=surenb@google.com \
    --cc=vbabka@kernel.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