From: Jakub Kicinski <kuba@kernel.org>
To: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Eric Dumazet <edumazet@google.com>,
Dmitry Vyukov <dvyukov@google.com>,
"David S. Miller" <davem@davemloft.net>,
LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] ref_tracker: add stack_depot_save() failure handling to ref_tracker_alloc()
Date: Mon, 29 May 2023 19:05:26 -0700 [thread overview]
Message-ID: <20230529190526.65d13658@kernel.org> (raw)
In-Reply-To: <5fa8dfeb-8eb6-0de0-a335-e0b4336c29e0@I-love.SAKURA.ne.jp>
On Sat, 27 May 2023 20:04:11 +0900 Tetsuo Handa wrote:
> stack_depot_save() cannot accept __GFP_NOFAIL flag because
> __stack_depot_save() drops gfp flags which are not in
> GFP_KERNEL | GFP_ATOMIC | __GFP_NOWARN. Also, changing
> __stack_depot_save() to accept __GFP_NOFAIL is not possible
> because rmqueue() does not want __GFP_NOFAIL flag for
> order == DEPOT_POOL_ORDER allocation request.
>
> Therefore, assume that stack_depot_save(GFP_KERNEL | __GFP_NOFAIL) from
> ref_tracker_alloc() can silently fail, and emit "unreliable refcount
> tracker." message.
It's probably a good idea to CC netdev@vger. I'm not sure if anyone
will pick this up from LKML.
For the patch itself - I'm not sure it's needed, even if we don't
record the stack we'll have a tracker object and still detect the leak.
So printing the "unreliable refcount" message is not very precise.
At least to me; Eric's opinion matters most.
next prev parent reply other threads:[~2023-05-30 2:06 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-05-27 11:04 [PATCH] ref_tracker: add stack_depot_save() failure handling to ref_tracker_alloc() Tetsuo Handa
2023-05-30 2:05 ` Jakub Kicinski [this message]
2023-05-30 7:22 ` Eric Dumazet
2023-05-30 9:51 ` Tetsuo Handa
2023-05-30 10:06 ` Eric Dumazet
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=20230529190526.65d13658@kernel.org \
--to=kuba@kernel.org \
--cc=davem@davemloft.net \
--cc=dvyukov@google.com \
--cc=edumazet@google.com \
--cc=linux-kernel@vger.kernel.org \
--cc=penguin-kernel@I-love.SAKURA.ne.jp \
/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.