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Date: Tue, 23 Apr 2013 13:24:04 -0400
Message-ID: <CAG6tG3zcOdkA5QOBhaDzmMvcFSCwbfRAyKuRwXdn6ipOJhTVZQ@mail.gmail.com>
Subject: Re: [BUG] staging: android: ashmem: Deadlock during ashmem_shrink
From: Robert Love <rlove@google.com>
To: Shankar Brahadeeswaran <shankoo77@gmail.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Bjorn Bringert <bringert@google.com>,
        Al Viro <viro@zeniv.linux.org.uk>, devel@driverdev.osuosl.org,
        Hugh Dickins <hughd@google.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Anjana V Kumar <anjanavk12@gmail.com>
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On Tue, Apr 23, 2013 at 12:20 PM, Shankar Brahadeeswaran
<shankoo77@gmail.com> wrote:

> I'm unable to think of a straight forward way to fix this. If you have
> any suggestions please provide the same.
> If we are unable to solve this too with minor mods, as suggested by
> Dan we have to re-look at the locking in this driver.

This doesn't look insurmountable. It isn't necessary AFAICT to hold
ashmem_mutex across shmem_file_setup.

Patch attached (untested).

           Robert

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