Vulkan: do not replace hardware GPU with software renderer#781
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IgorAlexey wants to merge 3 commits intoDiligentGraphics:masterfrom
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Vulkan: do not replace hardware GPU with software renderer#781IgorAlexey wants to merge 3 commits intoDiligentGraphics:masterfrom
IgorAlexey wants to merge 3 commits intoDiligentGraphics:masterfrom
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When no discrete GPU is present, SelectPhysicalDevice iterates all physical devices and keeps overwriting SelectedPhysicalDevice without breaking, because the break only fires for VK_PHYSICAL_DEVICE_TYPE_DISCRETE_GPU. On Linux with Mesa, a CPU-type software renderer (llvmpipe) is always enumerated alongside the real hardware device. On a system with only an integrated GPU the loop would iterate past the iGPU, land on llvmpipe as the last entry, and silently return it as the selected device—making the application run entirely on software rendering with no warning. Fix this by skipping CPU-type devices when a hardware device has already been selected. A CPU-type device is still accepted as a last resort when no hardware GPU is found at all, so the fallback behavior is preserved. Tested on an Intel Core Ultra 7 258V (Lunar Lake, Arc 130V/140V iGPU) running Fedora 43 with Mesa 25.3.6.
Contributor
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I am thinking, maybe make it even more reliable by prioritizing SOFTWARE < INTEGRATED < DISCRETE |
Author
I agree, makes things more predictable |
Author
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Is this good? |
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When no discrete GPU is present, SelectPhysicalDevice iterates all physical devices and keeps overwriting SelectedPhysicalDevice without breaking, because the break only fires for VK_PHYSICAL_DEVICE_TYPE_DISCRETE_GPU.
On Linux with Mesa, a CPU-type software renderer (llvmpipe) is always enumerated alongside the real hardware device. On a system with only an integrated GPU the loop would iterate past the iGPU, land on llvmpipe as the last entry, and silently return it as the selected device, making the application run entirely on software rendering with no warning.
Fix this by skipping CPU-type devices when a hardware device has already been selected. A CPU-type device is still accepted as a last resort when no hardware GPU is found at all, so the fallback behavior is preserved.
Tested on an Intel Core Ultra 7 258V (Lunar Lake, Arc 130V/140V iGPU) running Fedora 43 with Mesa 25.3.6.