Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Subject: Re: [PATCH] kobject: Make sure the parent does not get released
 before its children
To:     Brendan Higgins <brendanhiggins@google.com>,
        Heikki Krogerus <heikki.krogerus@linux.intel.com>
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Naresh Kamboju <naresh.kamboju@linaro.org>,
        kernel test robot <rong.a.chen@intel.com>,
        "Rafael J. Wysocki" <rafael@kernel.org>
References: <20200513151840.36400-1-heikki.krogerus@linux.intel.com>
 <CAFd5g44d+VCSimjboPkf-NF1eCdbq6Uy+pabNftB8p5Lj2yc1A@mail.gmail.com>
From:   Randy Dunlap <rdunlap@infradead.org>
Message-ID: <e51d4ce4-42ba-8c89-21b4-082c7158a9a9@infradead.org>
Date:   Wed, 13 May 2020 16:14:51 -0700
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101
 Thunderbird/68.8.0
MIME-Version: 1.0
In-Reply-To: <CAFd5g44d+VCSimjboPkf-NF1eCdbq6Uy+pabNftB8p5Lj2yc1A@mail.gmail.com>
Content-Type: text/plain; charset=utf-8
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On 5/13/20 2:30 PM, Brendan Higgins wrote:
> On Wed, May 13, 2020 at 8:18 AM Heikki Krogerus
> <heikki.krogerus@linux.intel.com> wrote:
>>
>> In the function kobject_cleanup(), kobject_del(kobj) is
>> called before the kobj->release(). That makes it possible to
>> release the parent of the kobject before the kobject itself.
>>
>> To fix that, adding function __kboject_del() that does
>> everything that kobject_del() does except release the parent
>> reference. kobject_cleanup() then calls __kobject_del()
>> instead of kobject_del(), and separately decrements the
>> reference count of the parent kobject after kobj->release()
>> has been called.
>>
>> Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
>> Reported-by: kernel test robot <rong.a.chen@intel.com>
>> Fixes: 7589238a8cf3 ("Revert "software node: Simplify software_node_release() function"")
>> Cc: Brendan Higgins <brendanhiggins@google.com>
>> Cc: Randy Dunlap <rdunlap@infradead.org>
>> Suggested-by: "Rafael J. Wysocki" <rafael@kernel.org>
>> Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
> 
> Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
> Tested-by: Brendan Higgins <brendanhiggins@google.com>
> 

Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>

Thanks.
-- 
~Randy