From: Linus Torvalds <torvalds@linux-foundation.org>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
"Eric W. Biederman" <ebiederm@xmission.com>,
Joel Stanley <joel@jms.id.au>
Subject: Re: [PATCH 2/2] drivers: core: Remove glue dirs from sysfs earlier
Date: Sat, 30 Jun 2018 20:57:05 -0700 [thread overview]
Message-ID: <CA+55aFxqUyACDPBL4trTfGyJudg8P7YGazVGUW7-UaNFJiwZRQ@mail.gmail.com> (raw)
In-Reply-To: <675c0752ea41c9dc52c2a4b69f09fb9746207de3.camel@kernel.crashing.org>
On Sat, Jun 30, 2018 at 8:42 PM Benjamin Herrenschmidt
<benh@kernel.crashing.org> wrote:
>
> But what if something *else* still holds a reference to the kobject ?
> It could be anything really... t
But that's fine. Then the object will continue to exist, and the sysfs
file will continue to exist, and you won't get a new glue directory.
In fact, what you describe is a problem with *your* patch, exactly
because you introduce another counter that is *not* the reference
count, and now you have the problem with "old directory kobject is
still live, but I removed the sysfs part, and now I'm creating a new
object with the same name".
Hmm?
> It is and there's a WARN_ON about it inside kobject_get(). I don't
> think anybody argues against that, you are absolutely right.
No. That the zero kobject_get() will not result in a warning. It just
does a kref_get(), no warnings anywhere.
Yes, there is a kobject_get() warning, but that's about an
_uninitialized_ kobject, not a already released one! You will get no
warning that I can see from the "oh, you just got a stale one".
Linus
next prev parent reply other threads:[~2018-07-01 3:57 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <c40fe912fe008b1b531a3867e8784ed79d68023e.camel@kernel.crashing.org>
[not found] ` <CA+55aFxR0qg0yY-NWnH0DDruVWw8qRqp8=CRLq13p=TyxosJKw@mail.gmail.com>
2018-06-29 2:21 ` [PATCH 1/2] drivers: core: Don't try to use a dead glue_dir Benjamin Herrenschmidt
2018-06-30 19:45 ` Linus Torvalds
2018-07-07 16:48 ` Greg Kroah-Hartman
2018-07-09 23:44 ` Benjamin Herrenschmidt
2018-07-10 14:55 ` Greg Kroah-Hartman
2018-07-10 23:32 ` Benjamin Herrenschmidt
2018-07-10 23:55 ` Linus Torvalds
2018-07-11 0:07 ` Benjamin Herrenschmidt
2018-07-21 7:53 ` Greg Kroah-Hartman
2018-07-23 0:35 ` Benjamin Herrenschmidt
2018-07-07 16:51 ` Greg Kroah-Hartman
2018-07-09 23:50 ` Benjamin Herrenschmidt
2018-06-29 2:21 ` [PATCH 2/2] drivers: core: Remove glue dirs from sysfs earlier Benjamin Herrenschmidt
2018-06-29 13:56 ` Linus Torvalds
2018-06-29 13:57 ` Linus Torvalds
2018-06-30 1:04 ` Benjamin Herrenschmidt
2018-06-30 3:51 ` Benjamin Herrenschmidt
[not found] ` <edc7b03b9550ddcf1291ebf5a6dafd24f4455c23.camel@kernel.crashing.org>
[not found] ` <CA+55aFxS7OVEN5XrxceC5ibz780mhn-qRa50w1gVFjsz2JjMbw@mail.gmail.com>
[not found] ` <7eb06b499f2be366cf68c6b6588b16c603e6a567.camel@kernel.crashing.org>
2018-07-01 2:07 ` Linus Torvalds
2018-07-01 2:18 ` Linus Torvalds
2018-07-01 3:49 ` Benjamin Herrenschmidt
2018-07-01 3:42 ` Benjamin Herrenschmidt
2018-07-01 3:57 ` Linus Torvalds [this message]
2018-07-01 7:16 ` Benjamin Herrenschmidt
2018-07-01 17:04 ` Linus Torvalds
2018-07-01 23:36 ` Benjamin Herrenschmidt
2018-07-02 10:23 ` Benjamin Herrenschmidt
2018-07-02 19:24 ` Linus Torvalds
2018-07-03 0:57 ` Benjamin Herrenschmidt
2018-07-03 2:15 ` Linus Torvalds
2018-07-03 2:26 ` Linus Torvalds
2018-07-03 2:39 ` Benjamin Herrenschmidt
2018-07-03 5:22 ` Benjamin Herrenschmidt
2018-07-03 15:46 ` Tejun Heo
2018-07-04 1:10 ` Benjamin Herrenschmidt
[not found] ` <CA+55aFzKmzC-2_6+RsRRu9KfK_r=UGgLN2Q0hSNBV=ScGR7=8g@mail.gmail.com>
[not found] ` <6e3ca577f8dd5f3621d1054447d3f928a73dfcf9.camel@kernel.crashing.org>
[not found] ` <CA+55aFy+ZSu5cPzk887N-ZgXqvTB=Bp1JQYMWT1SZY81MqLH6Q@mail.gmail.com>
[not found] ` <1bc873980e7f63291fbe19dbc7e1607b8e126241.camel@kernel.crashing.org>
[not found] ` <20180707164241.GB16279@kroah.com>
[not found] ` <CA+55aFx-UX8nxewRFFWdBgYfPqfipnxaqJuJCUni9h4JvhoPFw@mail.gmail.com>
2018-07-10 0:29 ` [PATCH v2 " Benjamin Herrenschmidt
2018-07-10 0:33 ` Linus Torvalds
2018-07-10 1:37 ` Benjamin Herrenschmidt
2018-07-10 14:55 ` Greg Kroah-Hartman
2018-07-10 23:31 ` Benjamin Herrenschmidt
2018-07-03 2:37 ` [PATCH " Benjamin Herrenschmidt
2018-07-02 10:22 ` Benjamin Herrenschmidt
2018-07-01 3:52 ` Benjamin Herrenschmidt
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