From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Daniel Hiltgen <daniel@ollama.com>
Date: Sun, 30 Nov 2025 11:05:56 -0800
Subject: [PATCH] ggml: Export GPU UUIDs

---
 ggml/include/ggml-backend.h        |  1 +
 ggml/src/ggml-cuda/ggml-cuda.cu    | 67 +++++++++++++++++++++++++++---
 ggml/src/ggml-metal/ggml-metal.cpp |  1 +
 3 files changed, 63 insertions(+), 6 deletions(-)

diff --git a/ggml/include/ggml-backend.h b/ggml/include/ggml-backend.h
index c54ff98bf..229bf387b 100644
--- a/ggml/include/ggml-backend.h
+++ b/ggml/include/ggml-backend.h
@@ -158,6 +158,7 @@ extern "C" {
         const char * description;
         // device free memory in bytes
         size_t memory_free;
+        const char * id;
         // device total memory in bytes
         size_t memory_total;
         // device type
diff --git a/ggml/src/ggml-cuda/ggml-cuda.cu b/ggml/src/ggml-cuda/ggml-cuda.cu
index 5145c1e88..f641c1016 100644
--- a/ggml/src/ggml-cuda/ggml-cuda.cu
+++ b/ggml/src/ggml-cuda/ggml-cuda.cu
@@ -189,6 +189,51 @@ static int ggml_cuda_parse_id(char devName[]) {
 }
 #endif // defined(GGML_USE_HIP)
 
+static std::string ggml_cuda_parse_uuid(cudaDeviceProp prop, int device_num) {
+    char id[64];
+
+#if !defined(GGML_USE_HIP)
+    snprintf(id, sizeof(id),
+        "GPU-%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
+        (unsigned char)prop.uuid.bytes[0],
+        (unsigned char)prop.uuid.bytes[1],
+        (unsigned char)prop.uuid.bytes[2],
+        (unsigned char)prop.uuid.bytes[3],
+        (unsigned char)prop.uuid.bytes[4],
+        (unsigned char)prop.uuid.bytes[5],
+        (unsigned char)prop.uuid.bytes[6],
+        (unsigned char)prop.uuid.bytes[7],
+        (unsigned char)prop.uuid.bytes[8],
+        (unsigned char)prop.uuid.bytes[9],
+        (unsigned char)prop.uuid.bytes[10],
+        (unsigned char)prop.uuid.bytes[11],
+        (unsigned char)prop.uuid.bytes[12],
+        (unsigned char)prop.uuid.bytes[13],
+        (unsigned char)prop.uuid.bytes[14],
+        (unsigned char)prop.uuid.bytes[15]
+        );
+#else
+#ifdef _WIN32
+        snprintf(id, sizeof(id), "%d", device_num);
+#else
+    try {
+        std::string uuid = std::string(prop.uuid.bytes, 16);
+
+        size_t pos = 0;
+        unsigned long long v = stoull(uuid, &pos, 16);
+        if (v == 0 || pos != uuid.size() || (!uuid.empty() && uuid[0] == '-'))
+            throw std::invalid_argument("invalid uuid");
+
+        snprintf(id, sizeof(id), "GPU-%016llx", v);
+    } catch (const std::exception &e) {
+        snprintf(id, sizeof(id), "%d", device_num);
+    }
+#endif
+#endif
+
+    return id;
+}
+
 static ggml_cuda_device_info ggml_cuda_init() {
     ggml_cuda_device_info info = {};
 
@@ -255,22 +300,24 @@ static ggml_cuda_device_info ggml_cuda_init() {
                 info.devices[id].cc += prop.minor * 0x10;
             }
         }
-        GGML_LOG_INFO("  Device %d: %s, %s (0x%x), VMM: %s, Wave Size: %d\n",
+        GGML_LOG_INFO("  Device %d: %s, %s (0x%x), VMM: %s, Wave Size: %d, ID: %s\n",
                       id, prop.name, prop.gcnArchName, info.devices[id].cc & 0xffff,
-                      device_vmm ? "yes" : "no", prop.warpSize);
+                      device_vmm ? "yes" : "no", prop.warpSize, ggml_cuda_parse_uuid(prop, id).c_str());
 #elif defined(GGML_USE_MUSA)
         // FIXME: Ensure compatibility with varying warp sizes across different MUSA archs.
         info.devices[id].warp_size = 32;
         info.devices[id].smpbo = prop.sharedMemPerBlockOptin;
         info.devices[id].cc = GGML_CUDA_CC_OFFSET_MTHREADS + prop.major * 0x100;
         info.devices[id].cc += prop.minor * 0x10;
-        GGML_LOG_INFO("  Device %d: %s, compute capability %d.%d, VMM: %s\n",
-                        id, prop.name, prop.major, prop.minor, device_vmm ? "yes" : "no");
+        GGML_LOG_INFO("  Device %d: %s, compute capability %d.%d, VMM: %s, ID: %s\n",
+                        id, prop.name, prop.major, prop.minor, device_vmm ? "yes" : "no",
+                        ggml_cuda_parse_uuid(prop, id).c_str());
 #else
         info.devices[id].smpbo = prop.sharedMemPerBlockOptin;
         info.devices[id].cc = 100*prop.major + 10*prop.minor;
-        GGML_LOG_INFO("  Device %d: %s, compute capability %d.%d, VMM: %s\n",
-                        id, prop.name, prop.major, prop.minor, device_vmm ? "yes" : "no");
+        GGML_LOG_INFO("  Device %d: %s, compute capability %d.%d, VMM: %s, ID: %s\n",
+                        id, prop.name, prop.major, prop.minor, device_vmm ? "yes" : "no",
+                        ggml_cuda_parse_uuid(prop, id).c_str());
         std::string device_name(prop.name);
         if (device_name == "NVIDIA GeForce MX450") {
             turing_devices_without_mma.push_back({ id, device_name });
@@ -4110,6 +4157,7 @@ struct ggml_backend_cuda_device_context {
     std::string name;
     std::string description;
     std::string pci_bus_id;
+    std::string id;
 };
 
 static const char * ggml_backend_cuda_device_get_name(ggml_backend_dev_t dev) {
@@ -4198,6 +4246,11 @@ static bool ggml_backend_cuda_get_available_uma_memory(long * available_memory_k
 }
 #endif // defined(__linux__)
 
+static const char * ggml_backend_cuda_device_get_id(ggml_backend_dev_t dev) {
+    ggml_backend_cuda_device_context * ctx = (ggml_backend_cuda_device_context *)dev->context;
+    return ctx->id.c_str();
+}
+
 static void ggml_backend_cuda_device_get_memory(ggml_backend_dev_t dev, size_t * free, size_t * total) {
     ggml_backend_cuda_device_context * ctx = (ggml_backend_cuda_device_context *)dev->context;
     ggml_cuda_set_device(ctx->device);
@@ -4238,6 +4291,7 @@ static void ggml_backend_cuda_device_get_props(ggml_backend_dev_t dev, ggml_back
 
     props->name        = ggml_backend_cuda_device_get_name(dev);
     props->description = ggml_backend_cuda_device_get_description(dev);
+    props->id          = ggml_backend_cuda_device_get_id(dev);
     props->type        = ggml_backend_cuda_device_get_type(dev);
     props->device_id   = ctx->pci_bus_id.empty() ? nullptr : ctx->pci_bus_id.c_str();
     ggml_backend_cuda_device_get_memory(dev, &props->memory_free, &props->memory_total);
@@ -4833,6 +4887,7 @@ ggml_backend_reg_t ggml_backend_cuda_reg() {
                 cudaDeviceProp prop;
                 CUDA_CHECK(cudaGetDeviceProperties(&prop, i));
                 dev_ctx->description = prop.name;
+                dev_ctx->id = ggml_cuda_parse_uuid(prop, i);
 
                 char pci_bus_id[16] = {};
                 snprintf(pci_bus_id, sizeof(pci_bus_id), "%04x:%02x:%02x.0", prop.pciDomainID, prop.pciBusID, prop.pciDeviceID);
diff --git a/ggml/src/ggml-metal/ggml-metal.cpp b/ggml/src/ggml-metal/ggml-metal.cpp
index f2b7fe692..8fc1c2fb5 100644
--- a/ggml/src/ggml-metal/ggml-metal.cpp
+++ b/ggml/src/ggml-metal/ggml-metal.cpp
@@ -547,6 +547,7 @@ static enum ggml_backend_dev_type ggml_backend_metal_device_get_type(ggml_backen
 static void ggml_backend_metal_device_get_props(ggml_backend_dev_t dev, ggml_backend_dev_props * props) {
     props->name        = ggml_backend_metal_device_get_name(dev);
     props->description = ggml_backend_metal_device_get_description(dev);
+    props->id          = "0";
     props->type        = ggml_backend_metal_device_get_type(dev);
 
     ggml_backend_metal_device_get_memory(dev, &props->memory_free, &props->memory_total);
