Segfault in fullscreen on Wayland with NVIDIA Vulkan WSI (hybrid GPU)

mpv version and platform

• mpv v0.40.0
• libplacebo v7.349.0
• FFmpeg 7.1.1
• Ubuntu 25.10 (kernel 6.17.0-14-generic)
• GNOME Shell 49.0 / Mutter 49.0 (Wayland)
• NVIDIA driver 590.48.01 (proprietary, nvidia-dkms-590)
• Vulkan loader 1.4.321.0

Hardware

• Dell XPS 17 9700 (hybrid GPU, no MUX)
• iGPU: Intel CometLake-H GT2 [UHD Graphics] (PCI 00:02.0)
• dGPU: NVIDIA TU106M [GeForce RTX 2060 Max-Q] (PCI 01:00.0)
• Internal eDP panel (1920x1200 @ 60Hz), physically wired to Intel iGPU
• NVIDIA set as primary compositor GPU via udev rule (mutter-device-preferred-primary)

Description

mpv segfaults in the "vo" thread when entering Wayland fullscreen with Vulkan rendering on NVIDIA. The crash is inside libnvidia-glcore.so.590.48.01 during swapchain recreation triggered by xdg_toplevel.set_fullscreen.

Windowed mode works perfectly. Only true Wayland fullscreen crashes.

Reproducer

# Crashes — native Wayland Vulkan fullscreen:
mpv --fs --vo=gpu --gpu-api=vulkan \
    --vulkan-device="NVIDIA GeForce RTX 2060 with Max-Q Design" \
    any_video_file.mkv

# Works — windowed:
mpv --no-fs --vo=gpu --gpu-api=vulkan \
    --vulkan-device="NVIDIA GeForce RTX 2060 with Max-Q Design" \
    any_video_file.mkv

# Works — XWayland Vulkan context:
mpv --fs --vo=gpu --gpu-api=vulkan --gpu-context=x11vk \
    --vulkan-device="NVIDIA GeForce RTX 2060 with Max-Q Design" \
    any_video_file.mkv

# Works — maximized borderless (avoids xdg fullscreen):
mpv --no-fs --window-maximized=yes --no-border --vo=gpu --gpu-api=vulkan \
    --vulkan-device="NVIDIA GeForce RTX 2060 with Max-Q Design" \
    any_video_file.mkv

Key observations

• Not format-specific: crashes with any video file
• Not hwdec-specific: crashes with --hwdec=no (pure software decode)
• Not renderer-specific: crashes with both vo=gpu and vo=gpu-next
• Wayland WSI-specific: gpu-context=waylandvk crashes; gpu-context=x11vk works
• Fullscreen-specific: only xdg_toplevel.set_fullscreen triggers it; maximized does not
• OpenGL mode (--gpu-api=opengl) doesn't segfault but Mutter fails with: failed to import supplied dmabufs: Could not bind the given EGLImage to a CoglTexture2D

Stack trace

Thread 31 "vo" received signal SIGSEGV, Segmentation fault.
#0  0x00007fff19301132 in ??? () at /lib/x86_64-linux-gnu/libnvidia-glcore.so.590.48.01
#1  0x00007fff19301ea8 in ??? () at /lib/x86_64-linux-gnu/libnvidia-glcore.so.590.48.01
#2  0x00007fff19302a16 in ??? () at /lib/x86_64-linux-gnu/libnvidia-glcore.so.590.48.01
#3  0x00007ffff2f20635 in ??? () at /lib/x86_64-linux-gnu/libvulkan.so.1
#4  0x00007ffff39421d8 in ??? () at /lib/x86_64-linux-gnu/libplacebo.so.349
#5  0x00007ffff3943473 in ??? () at /lib/x86_64-linux-gnu/libplacebo.so.349
#6  0x0000555555759d44 in ??? ()  [mpv vo thread]
#7  0x00005555556dc81c in ??? ()  [mpv vo thread]
#8  0x00005555556e6030 in ??? ()  [mpv vo thread]
#9  0x00007ffff2ca3d64 in start_thread () at ./nptl/pthread_create.c:448

Registers at crash:
  rsi = 0xffffffffffffff  (corrupt size/offset value)

Analysis

The crash path is:

1. mpv enters fullscreen → Wayland compositor sends xdg_toplevel.configure with new dimensions
2. mpv's vo thread handles resize → libplacebo calls pl_swapchain_resize
3. libplacebo calls vkCreateSwapchainKHR to recreate swapchain
4. Inside libnvidia-glcore.so, the swapchain creation/teardown dereferences an invalid pointer, causing SIGSEGV

This appears to be the same underlying NVIDIA driver bug reported in:

• NVIDIA Forums: Vulkan fullscreen swapchain creation failure causes segfault on surface destruction
• Possibly related to libplacebo #200 (race in swapchain recreation)

Related mpv issues

• #14385 — Fullscreen video freezing in Wayland (NVIDIA)
• #17239 — Fullscreen + swapchain errors (NVIDIA 580/590)

Workaround

Use XWayland Vulkan context:

# ~/.config/mpv/mpv.conf
gpu-context=x11vk

The report names no mpv source file or test. Reproduce the native Wayland Vulkan command, then inspect the vo-thread fullscreen resize path where libplacebo recreates the swapchain; compare it with the working x11vk and maximized cases. Done means fullscreen no longer segfaults, or the issue is narrowed to the NVIDIA driver with a confirmed workaround.