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Subject: Re: [PATCH v2] initramfs: finish fput() before accessing any binary
 from initramfs
To: Al Viro <viro@ZenIV.linux.org.uk>
References: <20170124053636.30121-1-lokeshvutla@ti.com>
 <20170201122838.GC27291@ZenIV.linux.org.uk>
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        Nishanth Menon <nm@ti.com>,
        Muralidharan Karicheri <m-karicheri2@ti.com>
From: Lokesh Vutla <lokeshvutla@ti.com>
Message-ID: <9d9a2ffa-41a5-46a4-379b-d864cf9c6d7f@ti.com>
Date: Wed, 1 Feb 2017 19:15:53 +0530
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On Wednesday 01 February 2017 05:58 PM, Al Viro wrote:
> On Tue, Jan 24, 2017 at 11:06:36AM +0530, Lokesh Vutla wrote:
>> commit 4a9d4b024a31 ("switch fput to task_work_add") implements a
>> schedule_work() for completing fput(), but did not guarantee calling
>> __fput() after unpacking initramfs. Because of this, there is a
>> possibility that during boot a driver can see ETXTBSY when it tries
>> to load a binary from initramfs as fput() is still pending on that
>> binary. This patch makes sure that fput() is completed after unpacking
>> initramfs.
> 
> Umm...  Do we want it done in kernel_init(), then?  I have no objections
> against calling it in populate_rootfs(), and it looks like a sane place
> for that, but I wonder if the old callsite would remain needed after that...
> 

Hmm..You are right, the call in kernel_init() is unnecessary. Will post
an updated version.

Thanks and regards,
Lokesh