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Date: Tue, 26 Sep 2017 14:50:32 +0530
From: Aishwarya Pant <aishpant@gmail.com>
To: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@intel.com>,
	Jani Nikula <jani.nikula@linux.intel.com>,
	Sean Paul <seanpaul@chromium.org>, David Airlie <airlied@linux.ie>,
	dri-devel@lists.freedesktop.org, outreachy-kernel@googlegroups.com
Subject: Re: [PATCH] drm/gem: use new idr deletion interface to cleanup
 drm_gem_handle_delete()
Message-ID: <20170926092032.GA14610@aishwarya>
References: <20170925184728.GA8861@aishwarya>
 <150641713210.12806.16416549985820505069@mail.alporthouse.com>
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On Tue, Sep 26, 2017 at 10:12:12AM +0100, Chris Wilson wrote:
> Quoting Aishwarya Pant (2017-09-25 19:47:28)
> > The IDR deletion interface now returns the deleted entry or NULL if it was not
> > present. So we don't have to do the extra work of checking if we have a
> > reference on the drm_gem_object, this can be handled by checking the return
> > value from idr_remove() and the extra locks can be dropped.
> > 
> > Signed-off-by: Aishwarya Pant <aishpant@gmail.com>
> 
> This reintroduces the bug were the idr entry is available for reuse
> before the drivers have had the change to release their resources. So a
> new handle may be reused that is then hooked up to the old private data.
> See commit f6cd7daecff558fab2c45d15283d3e52f688342d
> Author: Chris Wilson <chris@chris-wilson.co.uk>
> Date:   Fri Apr 15 12:55:08 2016 +0100
> 
>     drm: Release driver references to handle before making it available again

Thanks, this makes sense now.

> -Chris