@@ -3045,9 +3045,11 @@ 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;
}
@@ -804,9 +804,11 @@ static int radeon_debugfs_ring_info(struct seq_file *m, void *data)
* 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;
}
This is a note to let you know that I have just added a patch titled drm/radeon: Make r100_cp_ring_info() and radeon_ring_gfx() safe (v2) to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue This patch is scheduled to be released in version 3.8.13.11. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.8.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From 38921933f2075f3c676c1ee1014523f86161b69d Mon Sep 17 00:00:00 2001 From: Alex Ivanov <gnidorah@p0n4ik.tk> Date: Fri, 20 Sep 2013 17:36:06 +0400 Subject: drm/radeon: Make r100_cp_ring_info() and radeon_ring_gfx() safe (v2) 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@p0n4ik.tk> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- drivers/gpu/drm/radeon/r100.c | 8 +++++--- drivers/gpu/drm/radeon/radeon_ring.c | 8 +++++--- 2 files changed, 10 insertions(+), 6 deletions(-) -- 1.8.1.2