[PATCH 11/13] drm/i915: Reject commands that would store to global HWS page

bradley.d.volkin
2014-02-18T18:19:53Z

From: Brad Volkin <bradley.d.volkin@intel.com>

PIPE_CONTROL and MI_FLUSH_DW have bits that would write to the
hardware status page. The driver stores request tracking info
there, so don't let userspace overwrite it.

v2: trailing comma fix, rebased

Signed-off-by: Brad Volkin <bradley.d.volkin@intel.com>
---
drivers/gpu/drm/i915/i915_cmd_parser.c | 24 +++++++++++++++++++++++-
drivers/gpu/drm/i915/i915_reg.h | 1 +
2 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/i915_cmd_parser.c b/drivers/gpu/drm/i915/i915_cmd_parser.c
index 1528549..f9aa01a 100644
--- a/drivers/gpu/drm/i915/i915_cmd_parser.c
+++ b/drivers/gpu/drm/i915/i915_cmd_parser.c
@@ -193,7 +193,8 @@ static const struct drm_i915_cmd_descriptor render_cmds[] = {
},
{
.offset = 1,
- .mask = PIPE_CONTROL_GLOBAL_GTT_IVB,
+ .mask = (PIPE_CONTROL_GLOBAL_GTT_IVB |
+ PIPE_CONTROL_STORE_DATA_INDEX),
.expected = 0,
.condition_offset = 1,
.condition_mask = PIPE_CONTROL_POST_SYNC_OP_MASK,
@@ -242,6 +243,13 @@ static const struct drm_i915_cmd_descriptor video_cmds[] = {
.expected = 0,
.condition_offset = 0,
.condition_mask = MI_FLUSH_DW_OP_MASK,
+ },
+ {
+ .offset = 0,
+ .mask = MI_FLUSH_DW_STORE_INDEX,
+ .expected = 0,
+ .condition_offset = 0,
+ .condition_mask = MI_FLUSH_DW_OP_MASK,
}}, ),
CMD( MI_CONDITIONAL_BATCH_BUFFER_END, SMI, !F, 0xFF, B,
.bits = {{
@@ -278,6 +286,13 @@ static const struct drm_i915_cmd_descriptor vecs_cmds[] = {
.expected = 0,
.condition_offset = 0,
.condition_mask = MI_FLUSH_DW_OP_MASK,
+ },
+ {
+ .offset = 0,
+ .mask = MI_FLUSH_DW_STORE_INDEX,
+ .expected = 0,
+ .condition_offset = 0,
+ .condition_mask = MI_FLUSH_DW_OP_MASK,
}}, ),
CMD( MI_CONDITIONAL_BATCH_BUFFER_END, SMI, !F, 0xFF, B,
.bits = {{
@@ -308,6 +323,13 @@ static const struct drm_i915_cmd_descriptor blt_cmds[] = {
.expected = 0,
.condition_offset = 0,
.condition_mask = MI_FLUSH_DW_OP_MASK,
+ },
+ {
+ .offset = 0,
+ .mask = MI_FLUSH_DW_STORE_INDEX,
+ .expected = 0,
+ .condition_offset = 0,
+ .condition_mask = MI_FLUSH_DW_OP_MASK,
}}, ),
CMD( COLOR_BLT, S2D, !F, 0x3F, S ),
CMD( SRC_COPY_BLT, S2D, !F, 0x3F, S ),
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index e683b31..46db649 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -335,6 +335,7 @@
#define GFX_OP_PIPE_CONTROL(len) ((0x3<<29)|(0x3<<27)|(0x2<<24)|(len-2))
#define PIPE_CONTROL_GLOBAL_GTT_IVB (1<<24) /* gen7+ */
#define PIPE_CONTROL_MMIO_WRITE (1<<23)
+#define PIPE_CONTROL_STORE_DATA_INDEX (1<<21)
#define PIPE_CONTROL_CS_STALL (1<<20)
#define PIPE_CONTROL_TLB_INVALIDATE (1<<18)
#define PIPE_CONTROL_QW_WRITE (1<<14)
--
1.8.3.2