From: Andrew Morton <akpm@linux-foundation.org>
To: Frank van der Linden <fvdl@google.com>
Cc: linux-mm@kvack.org, muchun.song@linux.dev,
linux-kernel@vger.kernel.org,
Marek Szyprowski <m.szyprowski@samsung.com>,
David Hildenbrand <david@redhat.com>
Subject: Re: [PATCH 1/2] mm/cma: drop incorrect alignment check in cma_init_reserved_mem
Date: Thu, 4 Apr 2024 13:15:49 -0700 [thread overview]
Message-ID: <20240404131549.27a454072f7e96530dce2d62@linux-foundation.org> (raw)
In-Reply-To: <20240404162515.527802-1-fvdl@google.com>
On Thu, 4 Apr 2024 16:25:14 +0000 Frank van der Linden <fvdl@google.com> wrote:
> cma_init_reserved_mem uses IS_ALIGNED to check if the size
> represented by one bit in the cma allocation bitmask is
> aligned with CMA_MIN_ALIGNMENT_BYTES (pageblock size).
>
> However, this is too strict, as this will fail if
> order_per_bit > pageblock_order, which is a valid configuration.
>
> We could check IS_ALIGNED both ways, but since both numbers are
> powers of two, no check is needed at all.
What are the userspace visible effects of this bug?
next prev parent reply other threads:[~2024-04-04 20:15 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-04-04 16:25 [PATCH 1/2] mm/cma: drop incorrect alignment check in cma_init_reserved_mem Frank van der Linden
2024-04-04 16:25 ` [PATCH 2/2] mm/hugetlb: pass correct order_per_bit to cma_declare_contiguous_nid Frank van der Linden
2024-04-04 18:56 ` Roman Gushchin
2024-04-04 19:40 ` Frank van der Linden
2024-04-04 20:45 ` Roman Gushchin
2024-04-04 20:13 ` David Hildenbrand
2024-04-04 20:52 ` Roman Gushchin
2024-04-04 22:02 ` Frank van der Linden
2024-04-04 22:20 ` Andrew Morton
2024-04-04 21:44 ` Frank van der Linden
2024-04-04 22:22 ` Frank van der Linden
2024-04-08 8:15 ` David Hildenbrand
2024-04-04 20:17 ` Andrew Morton
2024-04-04 21:58 ` Frank van der Linden
2024-04-07 8:02 ` Muchun Song
2024-04-04 20:15 ` Andrew Morton [this message]
2024-04-04 20:45 ` [PATCH 1/2] mm/cma: drop incorrect alignment check in cma_init_reserved_mem Frank van der Linden
[not found] ` <93eccef7-a559-4ad8-be0f-8cc99c00bd09@redhat.com>
2024-04-04 20:48 ` Frank van der Linden
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=20240404131549.27a454072f7e96530dce2d62@linux-foundation.org \
--to=akpm@linux-foundation.org \
--cc=david@redhat.com \
--cc=fvdl@google.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=m.szyprowski@samsung.com \
--cc=muchun.song@linux.dev \
/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