diff --git a/ggml/src/ggml-cpu/CMakeLists.txt b/ggml/src/ggml-cpu/CMakeLists.txt
index 8b0d60d..30de6c9 100644
--- a/ggml/src/ggml-cpu/CMakeLists.txt
+++ b/ggml/src/ggml-cpu/CMakeLists.txt
@@ -211,10 +211,13 @@ elseif (CMAKE_OSX_ARCHITECTURES STREQUAL "x86_64" OR CMAKE_GENERATOR_PLATFORM_LW
     endif()
 elseif (${CMAKE_SYSTEM_PROCESSOR} MATCHES "ppc64")
     message(STATUS "PowerPC detected")
-    execute_process(COMMAND bash -c "grep POWER10 /proc/cpuinfo | head -n 1"
-                   OUTPUT_VARIABLE POWER10_M)
-    string(FIND ${POWER10_M} "POWER10" substring_index)
-    if(${substring_index} GREATER_EQUAL 0)
+    execute_process(COMMAND bash -c "grep POWER10 /proc/cpuinfo | head -n 1" OUTPUT_VARIABLE POWER10_M)
+    string(FIND "${POWER10_M}" "POWER10" substring_index)
+    if (NOT DEFINED substring_index OR "${substring_index}" STREQUAL "")
+        set(substring_index -1)
+    endif()
+
+    if (${substring_index} GREATER_EQUAL 0)
        list(APPEND ARCH_FLAGS -mcpu=power10)
     elseif (${CMAKE_SYSTEM_PROCESSOR} MATCHES "ppc64le")
        list(APPEND ARCH_FLAGS -mcpu=powerpc64le)
diff --git a/ggml/src/ggml-metal/ggml-metal.m b/ggml/src/ggml-metal/ggml-metal.m
index 07711fc..7fc05fe 100644
--- a/ggml/src/ggml-metal/ggml-metal.m
+++ b/ggml/src/ggml-metal/ggml-metal.m
@@ -3553,7 +3553,7 @@ static enum ggml_status ggml_metal_graph_compute(
         dispatch_apply(n_cb, ctx->d_queue, ctx->encode_async);
 
         // wait for completion and check status of each command buffer
-        // needed to detect if the device ran out-of-memory for example (llama/1881)
+        // needed to detect if the device ran out-of-memory for example (ggml/1881)
         {
             id<MTLCommandBuffer> command_buffer = ctx->command_buffers[n_cb];
             [command_buffer waitUntilCompleted];
diff --git a/ggml/src/ggml-vulkan/ggml-vulkan.cpp b/ggml/src/ggml-vulkan/ggml-vulkan.cpp
index c02c356..04d671a 100644
--- a/ggml/src/ggml-vulkan/ggml-vulkan.cpp
+++ b/ggml/src/ggml-vulkan/ggml-vulkan.cpp
@@ -1763,7 +1763,8 @@ static void ggml_vk_print_gpu_info(size_t idx) {
     fp16 = fp16 && vk12_features.shaderFloat16;
 
     std::string device_name = props2.properties.deviceName.data();
-    std::cerr << GGML_VK_NAME << idx << ": " << device_name << " (" << driver_props.driverName << ") | uma: " << uma << " | fp16: " << fp16 << " | warp size: " << subgroup_size << std::endl;
+    GGML_LOG_DEBUG("ggml_vulkan: %d = %s (%s) | uma: %d | fp16: %d | warp size: %d\n",
+              idx, device_name.c_str(), driver_props.driverName, uma, fp16, subgroup_size);
 
     if (props2.properties.deviceType == vk::PhysicalDeviceType::eCpu) {
         std::cerr << "ggml_vulkan: Warning: Device type is CPU. This is probably not the device you want." << std::endl;
@@ -1821,8 +1822,7 @@ void ggml_vk_instance_init() {
         };
         validation_features.setPNext(nullptr);
         instance_create_info.setPNext(&validation_features);
-
-        std::cerr << "ggml_vulkan: Validation layers enabled" << std::endl;
+        GGML_LOG_DEBUG("ggml_vulkan: Validation layers enabled\n");
     }
     vk_instance.instance = vk::createInstance(instance_create_info);
 
@@ -1936,8 +1936,8 @@ void ggml_vk_instance_init() {
             vk_instance.device_indices.push_back(0);
         }
     }
+    GGML_LOG_DEBUG("ggml_vulkan: Found %d Vulkan devices:\n", vk_instance.device_indices.size());
 
-    std::cerr << "ggml_vulkan: Found " << vk_instance.device_indices.size() << " Vulkan devices:" << std::endl;
 
     for (size_t i = 0; i < vk_instance.device_indices.size(); i++) {
         ggml_vk_print_gpu_info(i);