From: Jann Horn <[email protected]>
To: Jens Axboe <[email protected]>
Cc: Glauber Costa <[email protected]>,
io-uring <[email protected]>,
Avi Kivity <[email protected]>
Subject: Re: Kernel BUG when registering the ring
Date: Wed, 12 Feb 2020 23:31:09 +0100 [thread overview]
Message-ID: <CAG48ez0ffvnfnPEemkKn1ZkGE-uAsAyBcAeJWdJ8j-eVeyaxfQ@mail.gmail.com> (raw)
In-Reply-To: <[email protected]>
On Tue, Feb 11, 2020 at 7:58 PM Jens Axboe <[email protected]> wrote:
[...]
> @@ -849,6 +857,8 @@ void io_wq_cancel_all(struct io_wq *wq)
> for_each_node(node) {
> struct io_wqe *wqe = wq->wqes[node];
>
> + if (!node_online(node))
> + continue;
> io_wq_for_each_worker(wqe, io_wqe_worker_send_sig, NULL);
> }
> rcu_read_unlock();
What is this going to do if a NUMA node is marked as offline (through
a call to node_set_offline() from try_offline_node()) while it has a
worker running, and then afterwards, with the worker still running,
io_wq_cancel_all() is executed? Is that going to potentially hang
because some op is still executing on that node's worker? Or is there
a reason why that can't happen?
[...]
> @@ -1084,6 +1100,8 @@ void io_wq_flush(struct io_wq *wq)
> for_each_node(node) {
> struct io_wqe *wqe = wq->wqes[node];
>
> + if (!node_online(node))
> + continue;
> init_completion(&data.done);
> INIT_IO_WORK(&data.work, io_wq_flush_func);
> data.work.flags |= IO_WQ_WORK_INTERNAL;
(io_wq_flush() is dead code since 05f3fb3c5397, right? Are there plans
to use it again?)
next prev parent reply other threads:[~2020-02-12 22:31 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-11 1:22 Kernel BUG when registering the ring Glauber Costa
2020-02-11 3:25 ` Jens Axboe
2020-02-11 3:45 ` Glauber Costa
2020-02-11 3:50 ` Jens Axboe
2020-02-11 13:01 ` Glauber Costa
2020-02-11 18:58 ` Jens Axboe
2020-02-11 19:23 ` Glauber Costa
2020-02-11 19:24 ` Jens Axboe
2020-02-12 22:31 ` Jann Horn [this message]
2020-02-13 15:20 ` Jens Axboe
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=CAG48ez0ffvnfnPEemkKn1ZkGE-uAsAyBcAeJWdJ8j-eVeyaxfQ@mail.gmail.com \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
/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