From: daniel@ffwll.ch (Daniel Vetter)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH v3 8/9] drm/rockchip: gem: Don't alloc/free gem buf when dev_private is invalid
Date: Thu, 6 Apr 2017 10:26:12 +0200 [thread overview]
Message-ID: <20170406082612.qmwyfjr5uwcp3arr@phenom.ffwll.local> (raw)
In-Reply-To: <20170405162839.k6q4b3tpt6t2s3zm@art_vandelay>
On Wed, Apr 05, 2017 at 12:28:40PM -0400, Sean Paul wrote:
> On Wed, Apr 05, 2017 at 04:29:26PM +0800, Jeffy Chen wrote:
> > After unbinding drm, the userspace may still has a chance to access
> > gem buf.
> >
> > Add a sanity check for a NULL dev_private to prevent that from
> > happening.
>
> I still don't understand how this is happening. You're saying that these hooks
> can be called after rockchip_drm_unbind() has finished?
Yeah this is supposed to be impossible. If it isn't, we need to debug and
fix this properly. This smells like pretty bad duct-tape ...
-Daniel
>
> Sean
>
> >
> > Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
> > ---
> >
> > Changes in v3:
> > Address Daniel Vetter <daniel@ffwll.ch>'s comments.
> > Update commit message.
> >
> > Changes in v2: None
> >
> > drivers/gpu/drm/rockchip/rockchip_drm_gem.c | 8 ++++++++
> > 1 file changed, 8 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c
> > index df9e570..205a3dc 100644
> > --- a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c
> > +++ b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c
> > @@ -184,6 +184,9 @@ static int rockchip_gem_alloc_buf(struct rockchip_gem_object *rk_obj,
> > struct drm_device *drm = obj->dev;
> > struct rockchip_drm_private *private = drm->dev_private;
> >
> > + if (!private)
> > + return -ENODEV;
> > +
> > if (private->domain)
> > return rockchip_gem_alloc_iommu(rk_obj, alloc_kmap);
> > else
> > @@ -208,6 +211,11 @@ static void rockchip_gem_free_dma(struct rockchip_gem_object *rk_obj)
> >
> > static void rockchip_gem_free_buf(struct rockchip_gem_object *rk_obj)
> > {
> > + struct drm_device *drm = rk_obj->base.dev;
> > +
> > + if (!drm->dev_private)
> > + return;
> > +
> > if (rk_obj->pages)
> > rockchip_gem_free_iommu(rk_obj);
> > else
> > --
> > 2.1.4
> >
>
> --
> Sean Paul, Software Engineer, Google / Chromium OS
> _______________________________________________
> dri-devel mailing list
> dri-devel at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel
--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
next prev parent reply other threads:[~2017-04-06 8:26 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-04-05 8:29 [PATCH v3 0/9] drm: rockchip: Fix rockchip drm unbind crash error Jeffy Chen
2017-04-05 8:29 ` [PATCH v3 4/9] drm/rockchip: cdn-dp: Don't try to release firmware when not loaded Jeffy Chen
2017-04-05 8:29 ` [PATCH v3 5/9] drm/rockchip: vop: Enable pm domain before vop_initial Jeffy Chen
2017-04-05 8:29 ` [PATCH v3 6/9] drm/rockchip: Reoder drm bind/unbind sequence Jeffy Chen
2017-04-05 8:29 ` [PATCH v3 7/9] drm/rockchip: Shutdown all crtcs when unbinding drm Jeffy Chen
2017-04-05 8:29 ` [PATCH v3 8/9] drm/rockchip: gem: Don't alloc/free gem buf when dev_private is invalid Jeffy Chen
2017-04-05 16:28 ` Sean Paul
2017-04-06 2:47 ` jeffy
2017-04-06 12:26 ` Sean Paul
2017-04-06 12:54 ` jeffy
2017-04-06 8:26 ` Daniel Vetter [this message]
2017-04-06 11:09 ` jeffy
2017-04-07 6:30 ` Daniel Vetter
2017-04-07 6:44 ` jeffy
2017-04-07 7:15 ` Daniel Vetter
2017-04-05 8:29 ` [PATCH v3 9/9] drm/rockchip: cdn-dp: Don't unregister audio dev when unbinding Jeffy Chen
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