tree 0ca178740172d26985af7ddf8325e85a544835be
parent 42baf21d91d4f52f5b9a4d11dc8e7b1e3b93de7c
author Alex Ivanov <gnidorah@p0n4ik.tk> 1379684166 +0400
committer Alex Deucher <alexander.deucher@amd.com> 1379712892 -0400

drm/radeon: Make r100_cp_ring_info() and radeon_ring_gfx() safe (v2)

Prevent NULL pointer dereference in case when radeon_ring_fini() did it's job.

Reading of r100_cp_ring_info and radeon_ring_gfx debugfs entries will lead to a KP if ring buffer was deallocated, e.g. on failed ring test.
Seen on PA-RISC machine having "radeon: ring test failed (scratch(0x8504)=0xCAFEDEAD)" issue.

v2: agd5f: add some parens around ring->ready check

Signed-off-by: Alex Ivanov <gnidorah@p0n4ik.tk>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org