From 91744960c138772928b602eb0091a082d7f7a508 Mon Sep 17 00:00:00 2001
From: Cameron Gutman <aicommander@gmail.com>
Date: Mon, 11 Mar 2024 02:42:25 -0500
Subject: [PATCH] Avoid broken fallback to cross-adapter NVENC encoding with
 KMS

---
 src/platform/linux/kmsgrab.cpp | 21 ++++++++++++++++++++-
 src/platform/linux/misc.cpp    |  6 +++---
 2 files changed, 23 insertions(+), 4 deletions(-)

diff --git a/src/platform/linux/kmsgrab.cpp b/src/platform/linux/kmsgrab.cpp
index a7a3256d..a567d703 100644
--- a/src/platform/linux/kmsgrab.cpp
+++ b/src/platform/linux/kmsgrab.cpp
@@ -108,6 +108,7 @@ namespace platf {
     using obj_prop_t = util::safe_ptr<drmModeObjectProperties, drmModeFreeObjectProperties>;
     using prop_t = util::safe_ptr<drmModePropertyRes, drmModeFreeProperty>;
     using prop_blob_t = util::safe_ptr<drmModePropertyBlobRes, drmModeFreePropertyBlob>;
+    using version_t = util::safe_ptr<drmVersion, drmFreeVersion>;
 
     using conn_type_count_t = std::map<std::uint32_t, std::uint32_t>;
 
@@ -364,6 +365,12 @@ namespace platf {
         return drmModeGetResources(fd.el);
       }
 
+      bool
+      is_nvidia() {
+        version_t ver { drmGetVersion(fd.el) };
+        return ver && ver->name && strncmp(ver->name, "nvidia-drm", 10) == 0;
+      }
+
       bool
       is_cursor(std::uint32_t plane_id) {
         auto props = plane_props(plane_id);
@@ -604,6 +611,12 @@ namespace platf {
             continue;
           }
 
+          // Skip non-Nvidia cards if we're looking for CUDA devices
+          if (mem_type == mem_type_e::cuda && !card.is_nvidia()) {
+            BOOST_LOG(debug) << file << " is not a CUDA device"sv;
+            continue;
+          }
+
           auto end = std::end(card);
           for (auto plane = std::begin(card); plane != end; ++plane) {
             // Skip unused planes
@@ -1576,7 +1589,7 @@ namespace platf {
 
   // A list of names of displays accepted as display_name
   std::vector<std::string>
-  kms_display_names() {
+  kms_display_names(mem_type_e hwdevice_type) {
     int count = 0;
 
     if (!fs::exists("/dev/dri")) {
@@ -1608,6 +1621,12 @@ namespace platf {
         continue;
       }
 
+      // Skip non-Nvidia cards if we're looking for CUDA devices
+      if (hwdevice_type == mem_type_e::cuda && !card.is_nvidia()) {
+        BOOST_LOG(debug) << file << " is not a CUDA device"sv;
+        continue;
+      }
+
       auto crtc_to_monitor = kms::map_crtc_to_monitor(card.monitors(conn_type_count));
 
       auto end = std::end(card);
diff --git a/src/platform/linux/misc.cpp b/src/platform/linux/misc.cpp
index 27b281ac..884c0e90 100644
--- a/src/platform/linux/misc.cpp
+++ b/src/platform/linux/misc.cpp
@@ -766,13 +766,13 @@ namespace platf {
 
 #ifdef SUNSHINE_BUILD_DRM
   std::vector<std::string>
-  kms_display_names();
+  kms_display_names(mem_type_e hwdevice_type);
   std::shared_ptr<display_t>
   kms_display(mem_type_e hwdevice_type, const std::string &display_name, const video::config_t &config);
 
   bool
   verify_kms() {
-    return !kms_display_names().empty();
+    return !kms_display_names(mem_type_e::unknown).empty();
   }
 #endif
 
@@ -798,7 +798,7 @@ namespace platf {
     if (sources[source::WAYLAND]) return wl_display_names();
 #endif
 #ifdef SUNSHINE_BUILD_DRM
-    if (sources[source::KMS]) return kms_display_names();
+    if (sources[source::KMS]) return kms_display_names(hwdevice_type);
 #endif
 #ifdef SUNSHINE_BUILD_X11
     if (sources[source::X11]) return x11_display_names();