Am 05.12.2016 um 08:27 schrieb Daniel Vetter:
On Sat, Dec 03, 2016 at 03:47:00PM +0100, Nicolai Stange wrote:Since commit 8a357d10043c ("drm: Nerf DRM_CONTROL nodes"), a struct drm_device's ->control member is always NULL. In the case of CONFIG_DEBUG_FS=y, radeon_debugfs_add_files() accesses ->control->debugfs_root though. This results in the following Oops: BUG: unable to handle kernel NULL pointer dereference at 0000000000000018 IP: radeon_debugfs_add_files+0x90/0x100 [radeon] PGD 0 Oops: 0000 [#1] SMP [...] Call Trace: ? work_on_cpu+0xb0/0xb0 radeon_fence_driver_init+0x120/0x150 [radeon] si_init+0x122/0xd50 [radeon] ? _raw_spin_unlock_irq+0x2c/0x40 ? device_pm_check_callbacks+0xb3/0xc0 radeon_device_init+0x958/0xda0 [radeon] radeon_driver_load_kms+0x9a/0x210 [radeon] drm_dev_register+0xa9/0xd0 [drm] drm_get_pci_dev+0x9c/0x1e0 [drm] radeon_pci_probe+0xb8/0xe0 [radeon] [...] Fix this by omitting the drm_debugfs_create_files() call for the control minor debugfs directory which is now non-existent anyway. Fixes: 8a357d10043c ("drm: Nerf DRM_CONTROL nodes") Signed-off-by: Nicolai Stange <nicstange@xxxxxxxxx>Applied to drm-misc with Dave's irc ack, thanks for your patch.
If it's still worth it the patch is Reviewed-by: Christian König <christian.koenig@xxxxxxx>.
On the other hand when ->control is always NULL, why do we still have ->control anyway?
And BTW: Please double check the other drivers as well. Regards, Christian.
-Daniel--- Tested on top of next-20161202. That 8a357d10043c ("drm: Nerf DRM_CONTROL nodes") is in next since 20161201. drivers/gpu/drm/radeon/radeon_device.c | 6 ------ 1 file changed, 6 deletions(-) diff --git a/drivers/gpu/drm/radeon/radeon_device.c b/drivers/gpu/drm/radeon/radeon_device.c index 60a8920..8a1df2a 100644 --- a/drivers/gpu/drm/radeon/radeon_device.c +++ b/drivers/gpu/drm/radeon/radeon_device.c @@ -1949,9 +1949,6 @@ int radeon_debugfs_add_files(struct radeon_device *rdev, rdev->debugfs_count = i; #if defined(CONFIG_DEBUG_FS) drm_debugfs_create_files(files, nfiles, - rdev->ddev->control->debugfs_root, - rdev->ddev->control); - drm_debugfs_create_files(files, nfiles, rdev->ddev->primary->debugfs_root, rdev->ddev->primary); #endif @@ -1966,9 +1963,6 @@ static void radeon_debugfs_remove_files(struct radeon_device *rdev) for (i = 0; i < rdev->debugfs_count; i++) { drm_debugfs_remove_files(rdev->debugfs[i].files, rdev->debugfs[i].num_files, - rdev->ddev->control); - drm_debugfs_remove_files(rdev->debugfs[i].files, - rdev->debugfs[i].num_files, rdev->ddev->primary); } #endif -- 2.10.2 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
_______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
