From: Keith Busch <kbusch@kernel.org>
To: Daniel Wagner <dwagner@suse.de>
Cc: Christoph Hellwig <hch@lst.de>, Sagi Grimberg <sagi@grimberg.me>,
Chris Leech <cleech@redhat.com>,
linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org,
Dmitry Bogdanov <d.bogdanov@yadro.com>,
Daniel Wagner <wagi@kernel.org>
Subject: Re: [PATCH] nvme-tcp: fix usage of page_frag_cache
Date: Mon, 10 Aug 2026 17:40:21 -0600 [thread overview]
Message-ID: <anphZRzJvg0zSE6g@kbusch-mbp> (raw)
In-Reply-To: <20260716-nvme-tcp-page_fraq_cache-v1-1-ea660828cf93@kernel.org>
On Thu, Jul 16, 2026 at 04:42:19PM +0200, Daniel Wagner wrote:
> From: Dmitry Bogdanov <d.bogdanov@yadro.com>
>
> nvme uses page_frag_cache to preallocate PDU for each preallocated request
> of block device. Block devices are created in parallel threads,
> consequently page_frag_cache is used in not thread-safe manner.
> That leads to incorrect refcounting of backstore pages and premature free.
I was struggling to see how the nvme_tcp callback was happening
concurrently for the same queue. It's because you're using an io
scheduler, right? I don't think this applies if you don't have one
enabled.
Anyway, with that understanding, looks like a safe patch. Applied to
nvme-7.3.
next prev parent reply other threads:[~2026-08-10 23:40 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-07-16 14:42 [PATCH] nvme-tcp: fix usage of page_frag_cache Daniel Wagner
2026-08-06 12:46 ` Daniel Wagner
2026-08-10 23:40 ` Keith Busch [this message]
-- strict thread matches above, loose matches on Subject: below --
2025-09-29 11:19 Dmitry Bogdanov
2025-10-01 6:31 ` Chris Leech
2025-10-01 16:41 ` Dmitry Bogdanov
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=anphZRzJvg0zSE6g@kbusch-mbp \
--to=kbusch@kernel.org \
--cc=cleech@redhat.com \
--cc=d.bogdanov@yadro.com \
--cc=dwagner@suse.de \
--cc=hch@lst.de \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-nvme@lists.infradead.org \
--cc=sagi@grimberg.me \
--cc=wagi@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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.