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 for <linuxppc-dev@lists.ozlabs.org>; Thu, 30 Jun 2016 16:25:52 +1000 (AEST)
Date: Wed, 29 Jun 2016 23:24:42 -0700
From: Christoph Hellwig <hch@infradead.org>
To: Fam Zheng <famz@redhat.com>
Cc: linux-kernel@vger.kernel.org,
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 Shaohua Li <shli@kernel.org>, Ulf Hansson <ulf.hansson@linaro.org>,
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 dan.j.williams@intel.com
Subject: Re: [PATCH v2 00/12] gendisk: Generate uevent after attribute
 available
Message-ID: <20160630062442.GA19761@infradead.org>
References: <20160630015953.6888-1-famz@redhat.com>
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On Thu, Jun 30, 2016 at 09:59:41AM +0800, Fam Zheng wrote:
> Documentation/kobject.txt:
> > Use the KOBJ_ADD action for when the kobject is first added to the kernel.
> > This should be done only after any attributes or children of the kobject
> > have been initialized properly, as userspace will instantly start to look
> > for them when this call happens.
> 
> Unfortunately it seems impossible to fix this generally without touching the
> offending callers.  The approach I'm proposing here is adding a flag to
> suppress uevent in add_disk(), which is patch 1, then in later patches, convert
> any caller to only trigger the uevent when attributes are added.

We (or rather Dan) is touching most add_disk callers anyway for the
driverfs_dev removal.  Let's just pass the array of attributes to
a disk_add variant and solve the issue for real.