From: Stephen Hemminger <stephen@networkplumber.org>
To: bugzilla@dpdk.org
Cc: dev@dpdk.org
Subject: Re: [Bug 1277] memory_hotplug_lock deadlock during initialization
Date: Wed, 23 Aug 2023 07:56:16 -0700 [thread overview]
Message-ID: <20230823075616.45b2f971@hermes.local> (raw)
In-Reply-To: <bug-1277-3@http.bugs.dpdk.org/>
> It seems the issue arose due to changes in the DPDK read-write lock
> implementation. Following these changes, the RW-lock no longer supports
> recursion, implying that a single thread shouldn't obtain a read lock if it
> already possesses one. The problem arises during initialization: the
> rte_eal_memory_init() function acquires the memory_hotplug_lock, and later on,
> the sequence of calls eal_memalloc_init() -> rte_memseg_list_walk() acquires it
> again without releasing it. This scenario introduces the risk of a potential
> deadlock when concurrent write locks are applied to the same
> memory_hotplug_lock. To address this locally, we resolved the issue by
> replacing rte_memseg_list_walk() with rte_memseg_list_walk_thread_unsafe().
recursive read locks are bad idea and the fact that it worked before was
an accident.
Please send patch for review.
prev parent reply other threads:[~2023-08-23 14:56 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-08-23 14:02 bugzilla
2023-08-23 14:56 ` Stephen Hemminger [this message]
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=20230823075616.45b2f971@hermes.local \
--to=stephen@networkplumber.org \
--cc=bugzilla@dpdk.org \
--cc=dev@dpdk.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;
as well as URLs for NNTP newsgroup(s).