diff options
| author | Hans Verkuil <hverkuil@xs4all.nl> | 2017-06-07 22:05:57 +0300 |
|---|---|---|
| committer | Eric Anholt <eric@anholt.net> | 2017-06-13 02:48:03 +0300 |
| commit | 24bb206f32cdaa76c59444b62be51708dc16fbe8 (patch) | |
| tree | d6fd4f593743bd6b19216c02656247af505f93cf | |
| parent | dc629141c3336ae4b03c5fef5fb7bf1058752aed (diff) | |
| download | linux-24bb206f32cdaa76c59444b62be51708dc16fbe8.tar.xz | |
drm/vc4/vc4_bo.c: always set bo->resv
The bo->resv pointer could be NULL, leading to kernel oopses
like the one below.
This patch ensures that bo->resv is always set in vc4_create_object
ensuring that it is never NULL.
Thanks to Eric Anholt for pointing to the correct solution.
[ 19.738487] Unable to handle kernel NULL pointer dereference at virtual address 00000000
[ 19.746805] pgd = ffff8000275fc000
[ 19.750319] [00000000] *pgd=0000000000000000
[ 19.754715] Internal error: Oops: 96000004 [#1] PREEMPT SMP
[ 19.760369] Modules linked in: smsc95xx usbnet vc4 drm_kms_helper drm pwm_bcm2835 i2c_bcm2835 bcm2835_rng rng_core bcm2835_dma virt_dma
[ 19.772767] CPU: 0 PID: 1297 Comm: Xorg Not tainted 4.12.0-rc1-rpi3 #58
[ 19.779476] Hardware name: Raspberry Pi 3 Model B (DT)
[ 19.784688] task: ffff800028268000 task.stack: ffff800026c08000
[ 19.790705] PC is at ww_mutex_lock_interruptible+0x14/0xc0
[ 19.796329] LR is at vc4_submit_cl_ioctl+0x4fc/0x998 [vc4]
...
[ 20.240855] [<ffff0000088975f4>] ww_mutex_lock_interruptible+0x14/0xc0
[ 20.247528] [<ffff0000009b3ea4>] vc4_submit_cl_ioctl+0x4fc/0x998 [vc4]
[ 20.254372] [<ffff0000008f75f8>] drm_ioctl+0x180/0x438 [drm]
[ 20.260120] [<ffff00000821383c>] do_vfs_ioctl+0xa4/0x7d0
[ 20.265510] [<ffff000008213fe4>] SyS_ioctl+0x7c/0x98
[ 20.270550] [<ffff000008082f30>] el0_svc_naked+0x24/0x28
[ 20.275941] Code: d2800002 d5384103 910003fd f9800011 (c85ffc04)
[ 20.282527] ---[ end trace 1f6bd640ff32ae12 ]---
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Link: http://patchwork.freedesktop.org/patch/msgid/14e68768-6c92-2d74-92fd-196dbc50d8f7@xs4all.nl
| -rw-r--r-- | drivers/gpu/drm/vc4/vc4_bo.c | 12 |
1 files changed, 4 insertions, 8 deletions
diff --git a/drivers/gpu/drm/vc4/vc4_bo.c b/drivers/gpu/drm/vc4/vc4_bo.c index 80b2f9e55c5c..590c0912afc1 100644 --- a/drivers/gpu/drm/vc4/vc4_bo.c +++ b/drivers/gpu/drm/vc4/vc4_bo.c @@ -91,8 +91,7 @@ static void vc4_bo_destroy(struct vc4_bo *bo) vc4->bo_stats.num_allocated--; vc4->bo_stats.size_allocated -= obj->size; - if (bo->resv == &bo->_resv) - reservation_object_fini(bo->resv); + reservation_object_fini(&bo->_resv); drm_gem_cma_free_object(obj); } @@ -212,6 +211,8 @@ struct drm_gem_object *vc4_create_object(struct drm_device *dev, size_t size) vc4->bo_stats.num_allocated++; vc4->bo_stats.size_allocated += size; mutex_unlock(&vc4->bo_lock); + bo->resv = &bo->_resv; + reservation_object_init(bo->resv); return &bo->base.base; } @@ -250,12 +251,7 @@ struct vc4_bo *vc4_bo_create(struct drm_device *dev, size_t unaligned_size, return ERR_PTR(-ENOMEM); } } - bo = to_vc4_bo(&cma_obj->base); - - bo->resv = &bo->_resv; - reservation_object_init(bo->resv); - - return bo; + return to_vc4_bo(&cma_obj->base); } int vc4_dumb_create(struct drm_file *file_priv, |