summaryrefslogtreecommitdiff
path: root/drivers/gpu/drm/radeon/r100.c
diff options
context:
space:
mode:
authorAlex Ivanov <gnidorah@p0n4ik.tk>2013-09-20 17:36:06 +0400
committerAlex Deucher <alexander.deucher@amd.com>2013-09-21 01:34:52 +0400
commit0eb3448aa6b31fbf24c31756aba7940cac5ad6b8 (patch)
tree0ca178740172d26985af7ddf8325e85a544835be /drivers/gpu/drm/radeon/r100.c
parent42baf21d91d4f52f5b9a4d11dc8e7b1e3b93de7c (diff)
downloadlinux-0eb3448aa6b31fbf24c31756aba7940cac5ad6b8.tar.xz
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
Diffstat (limited to 'drivers/gpu/drm/radeon/r100.c')
-rw-r--r--drivers/gpu/drm/radeon/r100.c8
1 files changed, 5 insertions, 3 deletions
diff --git a/drivers/gpu/drm/radeon/r100.c b/drivers/gpu/drm/radeon/r100.c
index 24175717307b..d71333033b2b 100644
--- a/drivers/gpu/drm/radeon/r100.c
+++ b/drivers/gpu/drm/radeon/r100.c
@@ -2933,9 +2933,11 @@ static int r100_debugfs_cp_ring_info(struct seq_file *m, void *data)
seq_printf(m, "CP_RB_RPTR 0x%08x\n", rdp);
seq_printf(m, "%u free dwords in ring\n", ring->ring_free_dw);
seq_printf(m, "%u dwords in ring\n", count);
- for (j = 0; j <= count; j++) {
- i = (rdp + j) & ring->ptr_mask;
- seq_printf(m, "r[%04d]=0x%08x\n", i, ring->ring[i]);
+ if (ring->ready) {
+ for (j = 0; j <= count; j++) {
+ i = (rdp + j) & ring->ptr_mask;
+ seq_printf(m, "r[%04d]=0x%08x\n", i, ring->ring[i]);
+ }
}
return 0;
}