From 13e6d2ba006e9c9a0470d5e79cbd6cf90e481dfd Mon Sep 17 00:00:00 2001
From: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Date: Thu, 26 Jun 2025 10:52:46 +0200
Subject: [PATCH] radv: make sure to zero-initialize MSB of accel struct
 descriptor

RADV only uses the first 8 bytes but zero-initializing it make sure
the descriptor is invariant.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/35763>
---
 src/amd/vulkan/radv_descriptor_set.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/amd/vulkan/radv_descriptor_set.c b/src/amd/vulkan/radv_descriptor_set.c
index 2514f14122a..aaec27ed308 100644
--- a/src/amd/vulkan/radv_descriptor_set.c
+++ b/src/amd/vulkan/radv_descriptor_set.c
@@ -1150,7 +1150,10 @@ write_accel_struct(struct radv_device *device, void *ptr, VkDeviceAddress va)
       va = vk_acceleration_structure_get_va(accel_struct);
    }
 
-   memcpy(ptr, &va, sizeof(va));
+   uint64_t desc[2] = {va, 0};
+
+   assert(sizeof(desc) == RADV_ACCEL_STRUCT_DESC_SIZE);
+   memcpy(ptr, desc, RADV_ACCEL_STRUCT_DESC_SIZE);
 }
 
 static ALWAYS_INLINE void