From: Al Viro <viro@ZenIV.linux.org.uk>
To: Andrey Konovalov <andreyknvl@google.com>
Cc: Ingo Molnar <mingo@kernel.org>, Will Deacon <will.deacon@arm.com>,
Peter Zijlstra <peterz@infradead.org>,
Davidlohr Bueso <davidlohr@hp.com>,
linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
Dmitry Vyukov <dvyukov@google.com>,
Kostya Serebryany <kcc@google.com>,
ktsan@googlegroups.com
Subject: Re: Potential data race in dput and __d_lookup
Date: Thu, 20 Nov 2014 18:05:03 +0000 [thread overview]
Message-ID: <20141120180503.GN7996@ZenIV.linux.org.uk> (raw)
In-Reply-To: <CAAeHK+zQZ=sJYQA=BKLS2i7hu8NyXn6GXngvDqG9WD96yd9acg@mail.gmail.com>
On Thu, Nov 20, 2014 at 09:20:14PM +0400, Andrey Konovalov wrote:
> It seems that one thread increments 'dentry->d_lockref.count', while
> other does 'lockref_put_or_lock(&dentry->d_lockref)' without any
> synchronization.
>
> Could you confirm if this is a real race?
I can not. Increment in __d_lookup() is under ->d_lockref.lock (aka
->d_lock) and lockref_put_or_lock() is atomic wrt that.
prev parent reply other threads:[~2014-11-20 18:05 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-11-20 17:20 Potential data race in dput and __d_lookup Andrey Konovalov
2014-11-20 17:41 ` Will Deacon
2014-11-20 18:11 ` Al Viro
2014-11-20 18:05 ` Al Viro [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=20141120180503.GN7996@ZenIV.linux.org.uk \
--to=viro@zeniv.linux.org.uk \
--cc=andreyknvl@google.com \
--cc=davidlohr@hp.com \
--cc=dvyukov@google.com \
--cc=kcc@google.com \
--cc=ktsan@googlegroups.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@kernel.org \
--cc=peterz@infradead.org \
--cc=will.deacon@arm.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 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.