From: Matthew Wilcox <willy@infradead.org>
To: Hillf Danton <hdanton@sina.com>
Cc: "Liam R. Howlett" <Liam.Howlett@oracle.com>,
Andrew Morton <akpm@linux-foundation.org>,
maple-tree@lists.infradead.org, linux-mm@kvack.org,
linux-kernel@vger.kernel.org,
"Paul E. McKenney" <paulmck@kernel.org>,
syzbot+036af2f0c7338a33b0cd@syzkaller.appspotmail.com
Subject: Re: [PATCH] maple_tree: Remove rcu_read_lock() from mt_validate()
Date: Tue, 20 Aug 2024 23:53:58 +0100 [thread overview]
Message-ID: <ZsUehuMKf1dfRfJI@casper.infradead.org> (raw)
In-Reply-To: <20240820175417.2782532-1-Liam.Howlett@oracle.com>
On Wed, Aug 21, 2024 at 06:38:45AM +0800, Hillf Danton wrote:
Hillf, your email client is STILL broken. It's using the same message
ID as the email it's replying to, which causes all kinds of problems.
Please fix it or change to a different client.
> On Tue, 20 Aug 2024 13:54:17 -0400 "Liam R. Howlett" <Liam.Howlett@Oracle.com>
> >
> > The write lock should be held when validating the tree to avoid updates
> > racing with checks. Holding the rcu read lock during a large tree
> > validation may also cause a prolonged rcu read window.
> >
> >From the rcu stall's view, holding spin lock plays the same role of rcu
> read lock, so what are you fixing by simply dropping rcu read lock?
He's not holding a spinlock, he's holding a mutex, which has very
different properties.
prev parent reply other threads:[~2024-08-20 22:54 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-08-20 17:54 Liam R. Howlett
2024-08-20 22:38 ` Hillf Danton
2024-08-20 22:53 ` Matthew Wilcox [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=ZsUehuMKf1dfRfJI@casper.infradead.org \
--to=willy@infradead.org \
--cc=Liam.Howlett@oracle.com \
--cc=akpm@linux-foundation.org \
--cc=hdanton@sina.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=maple-tree@lists.infradead.org \
--cc=paulmck@kernel.org \
--cc=syzbot+036af2f0c7338a33b0cd@syzkaller.appspotmail.com \
/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