Mesa (staging/20.3): radv: round-up num_records division in radv_flush_vertex_descriptors

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Module: Mesa
Branch: staging/20.3
Commit: 2564042ab99cee8e34d5254bc5991ef9f7c487e6
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=2564042ab99cee8e34d5254bc5991ef9f7c487e6

Author: Rhys Perry <pendingchaos02 at gmail.com>
Date:   Mon Nov 30 15:44:08 2020 +0000

radv: round-up num_records division in radv_flush_vertex_descriptors

Vertex attribute bounds checking is supposed to be done per-attribute:
   is_oob = index * stride + attrib_offset + attrib_size > buffer_size
but we were obtaining num_records by dividing the buffer size by the
stride, making it per-vertex:
   is_oob = index * stride + (stride - 1) >= buffer_size

An example from Dead Cells (Wine) is:
attribute bindings: 0, 1, 2
attribute formats: r32g32, r32g32, r32g32b32a32
attribute offsets: 0, 0, 0
binding buffers: all the same buffer
binding offsets: 0, 8, 16
binding sizes: 128, 120, 112
binding strides: 32, 32, 32

Workaround this issue without switching to per-attribute descriptors by
rounding up the division. This is still incorrect, but it should now no
longer consider in-bounds attributes out-of-bounds.

Signed-off-by: Rhys Perry <pendingchaos02 at gmail.com>
Reviewed-by: Samuel Pitoiset <samuel.pitoiset at gmail.com>
Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/3796
Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/4199
Cc: mesa-stable
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/9557>

---

 src/amd/vulkan/radv_cmd_buffer.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/amd/vulkan/radv_cmd_buffer.c b/src/amd/vulkan/radv_cmd_buffer.c
index 10c4bb46d83..7e0c22626e5 100644
--- a/src/amd/vulkan/radv_cmd_buffer.c
+++ b/src/amd/vulkan/radv_cmd_buffer.c
@@ -2797,7 +2797,7 @@ radv_flush_vertex_descriptors(struct radv_cmd_buffer *cmd_buffer,
 			}
 
 			if (cmd_buffer->device->physical_device->rad_info.chip_class != GFX8 && stride)
-				num_records /= stride;
+				num_records = DIV_ROUND_UP(num_records, stride);
 
 			uint32_t rsrc_word3 = S_008F0C_DST_SEL_X(V_008F0C_SQ_SEL_X) |
 					      S_008F0C_DST_SEL_Y(V_008F0C_SQ_SEL_Y) |