This is a note to let you know that I've just added the patch titled drm/radeon: Make r100_cp_ring_info() and radeon_ring_gfx() safe (v2) to the 3.11-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-radeon-make-r100_cp_ring_info-and-radeon_ring_gfx-safe-v2.patch and it can be found in the queue-3.11 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 0eb3448aa6b31fbf24c31756aba7940cac5ad6b8 Mon Sep 17 00:00:00 2001 From: Alex Ivanov <gnidorah@xxxxxxxxx> Date: Fri, 20 Sep 2013 17:36:06 +0400 Subject: drm/radeon: Make r100_cp_ring_info() and radeon_ring_gfx() safe (v2) From: Alex Ivanov <gnidorah@xxxxxxxxx> commit 0eb3448aa6b31fbf24c31756aba7940cac5ad6b8 upstream. 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@xxxxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/radeon/r100.c | 8 +++++--- drivers/gpu/drm/radeon/radeon_ring.c | 8 +++++--- 2 files changed, 10 insertions(+), 6 deletions(-) --- a/drivers/gpu/drm/radeon/r100.c +++ b/drivers/gpu/drm/radeon/r100.c @@ -2926,9 +2926,11 @@ static int r100_debugfs_cp_ring_info(str 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; } --- a/drivers/gpu/drm/radeon/radeon_ring.c +++ b/drivers/gpu/drm/radeon/radeon_ring.c @@ -846,9 +846,11 @@ static int radeon_debugfs_ring_info(stru * packet that is the root issue */ i = (ring->rptr + ring->ptr_mask + 1 - 32) & ring->ptr_mask; - for (j = 0; j <= (count + 32); j++) { - seq_printf(m, "r[%5d]=0x%08x\n", i, ring->ring[i]); - i = (i + 1) & ring->ptr_mask; + if (ring->ready) { + for (j = 0; j <= (count + 32); j++) { + seq_printf(m, "r[%5d]=0x%08x\n", i, ring->ring[i]); + i = (i + 1) & ring->ptr_mask; + } } return 0; } Patches currently in stable-queue which might be from gnidorah@xxxxxxxxx are queue-3.11/drm-radeon-disable-tests-benchmarks-if-accel-is-disabled.patch queue-3.11/drm-radeon-make-r100_cp_ring_info-and-radeon_ring_gfx-safe-v2.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html