Crash when using gpu-next on AMD 5800H due to libplacebo assertion failure

werico

Hi, I’m encountering a reproducible crash when using a custom mpv-1.dll with gpu-next and vulkan backend on a Beelink SER5 mini PC (AMD Ryzen 7 5800H, Windows 11).

Steps to Reproduce

Replace mpv-1.dll with dev build (e.g., mpv-dev-i686-20241227-git-379c078).

Patch Stremio executable to enable MPV config reading (as suggested here: https://github.com/Stremio/stremio-shell/issues/81#issuecomment-1737716993).

Use input.conf with key apply-profile gpu-next

Launch a video.

Expected Behavior

Video should play using gpu-next profile.

Actual Behavior

Stremio crashes immediately. Stremio logs show the following assertion failure:

Assertion failed: gpu->limits.max_vbo_size <= gpu->limits.max_buf_size in ../../../../../src_packages/libplacebo/src/gpu/utils.c:160

Additional Info

This issue does not occur on my other PC with NVIDIA GPU — only on the Beelink mini PC.

If I switch to opengl, the crash stops but MPV video output window is gone entirely.

MPV itself works standalone with gpu-next and Vulkan — only crashes inside Stremio.

System: Windows 11, AMD 5800H

Workarounds Tried

Different MPV builds

Changing API to opengl (avoids crash but breaks video window)

<details>
<summary>Click here to see Log</summary>

hls executables located ->  {
  ffmpeg: 'C:\\Users\\aydin\\AppData\\Local\\Programs\\LNV\\Stremio-4\\ffmpeg.exe',
  ffsplit: null,
  ffprobe: 'C:\\Users\\aydin\\AppData\\Local\\Programs\\LNV\\Stremio-4\\ffprobe.exe'
}
Using app path -> C:\Users\aydin\AppData\Roaming\stremio\stremio-server
Enabling casting...
(node:4348) [DEP0005] DeprecationWarning: Buffer() is deprecated due to security and usability issues. Please use the Buffer.alloc(), Buffer.allocUnsafe(), or Buffer.from() methods instead.
(Use `stremio-runtime --trace-deprecation ...` to show where the warning was created)
Assertion failed: gpu->limits.max_vbo_size <= gpu->limits.max_buf_size in ../../../../../src_packages/libplacebo/src/gpu/utils.c:160

</details>

support7

Here are some potential solutions:
①. Update AMD graphics card driver
Go to AMD official website to download the latest graphics card driver, especially the version that includes Vulkan optimization update.

② Force to skip assertion check
Edit mpv.conf or Stremio’s MPV configuration file and add:
vo=gpu-next
vulkan-disable-asserts=yes # Skip assertion check

③ Downgrade libplacebo version
If you compile MPV yourself, use an older version of libplacebo (such as v5.229.0):
git clone -b v5.229.0 https://code.videolan.org/videolan/libplacebo.git
cd libplacebo && meson build && ninja -C build

④MPV configuration optimization Try adding the following parameter combination in mpv.conf:
vo=gpu-next
gpu-api=vulkan
vulkan-disable-fsaa=yes
vulkan-queue-count=1
If it still crashes, try reducing the buffer size:
gpu-context=winvk
vulkan-swap-mode=fifo

werico

I tried your solutions, but they didn’t work. Also the option vulkan-disable-asserts=yes doesn’t exist—MPV doesn’t have a setting like that. Could you help further? Do you need any additional logs?

support7

Here are some potential solutions:
① Switch to 64-bit MPV Build
Stremio is a 64-bit application. Replace the custom mpv-1.dll with a 64-bit (x86_64) build:
Download a 64-bit MPV dev build (e.g., mpv-dev-x86_64).
Replace mpv-1.dll in Stremio’s directory with the 64-bit version.

② Use D3D11 Instead of Vulkan
If the crash persists, force MPV to use Direct3D 11 with gpu-next:

In mpv.conf, add:
ini
vo=gpu-next
gpu-api=d3d11

③ (Optional) Adjust Libplacebo Limits
If you compile MPV yourself, modify libplacebo’s assertion check in src/gpu/utils.c:

Change line 160 from:
c
assert(gpu->limits.max_vbo_size <= gpu->limits.max_buf_size);
to:
c
if (gpu->limits.max_vbo_size > gpu->limits.max_buf_size) gpu->limits.max_vbo_size = gpu->limits.max_buf_size;

werico

Event Viewer log:

Log Name: Application
Source: Application Error
Date: 22.04.2025 01:41:42
Event ID: 1000
Task Category: Application Crashing Events
Level: Error
Keywords:
User: AYDN\aydin
Computer: aydn
Description:
Faulting application name: stremio.exe, version: 0.0.0.0, time stamp: 0×6603f767
Faulting module name: ucrtbase.dll, version: 10.0.22621.3593, time stamp: 0×84b62951
Exception code: 0xc0000409
Fault offset: 0×0009e3bb
Faulting process id: 0×0×29C4
Faulting application start time: 0×0×1DBB30E769D45D7
Faulting application path: C:\Users\aydin\AppData\Local\Programs\LNV\Stremio-4\stremio.exe
Faulting module path: C:\WINDOWS\System32\ucrtbase.dll
Report Id: daabbfb1-7a98-4208-8cec-0b8ff4af85d9
Faulting package full name:
Faulting package-relative application ID:
Event Xml:
<Event xmlns=“http://schemas.microsoft.com/win/2004/08/events/event”>
<System>
<Provider Name=“Application Error” Guid=“{a0e9b465-b939-57d7-b27d-95d8e925ff57}” />
<EventID>1000</EventID>
<Version>0</Version>
<Level>2</Level>
<Task>100</Task>
<Opcode>0</Opcode>
<Keywords>0×8000000000000000</Keywords>
<TimeCreated SystemTime=“2025-04-21T22:41:42.0703016Z” />
<EventRecordID>19337</EventRecordID>
<Correlation />
<Execution ProcessID=“7568” ThreadID=“7588” />
<Channel>Application</Channel>
<Computer>aydn</Computer>
<Security UserID=“S-1-5-21-1037397759-3751909605-3073522692-1001” />
</System>
<EventData>
<Data Name=“AppName”>stremio.exe</Data>
<Data Name=“AppVersion”>0.0.0.0</Data>
<Data Name=“AppTimeStamp”>6603f767</Data>
<Data Name=“ModuleName”>ucrtbase.dll</Data>
<Data Name=“ModuleVersion”>10.0.22621.3593</Data>
<Data Name=“ModuleTimeStamp”>84b62951</Data>
<Data Name=“ExceptionCode”>c0000409</Data>
<Data Name=“FaultingOffset”>0009e3bb</Data>
<Data Name=“ProcessId”>0×29c4</Data>
<Data Name=“ProcessCreationTime”>0×1dbb30e769d45d7</Data>
<Data Name=“AppPath”>C:\Users\aydin\AppData\Local\Programs\LNV\Stremio-4\stremio.exe</Data>
<Data Name=“ModulePath”>C:\WINDOWS\System32\ucrtbase.dll</Data>
<Data Name=“IntegratorReportId”>daabbfb1-7a98-4208-8cec-0b8ff4af85d9</Data>
<Data Name=“PackageFullName”>
</Data>
<Data Name=“PackageRelativeAppId”>
</Data>
</EventData>
</Event>

</details>

support6

werico
Step-by-Step Solution

Ensure Correct MPV Architecture
Problem: Stremio is 64-bit, so using a 32-bit (i686) MPV build can cause compatibility issues.

Fix: Download the 64-bit (x86_64) MPV dev build from mpv’s official repository https://sourceforge.net/projects/mpv-player-windows/files/ and replace mpv-1.dll in Stremio’s directory with the 64-bit version.

Bypass the Libplacebo Assertion
Problem: The assertion max_vbo_size <= max_buf_size fails due to driver-reported values on AMD hardware.

Fix:

Modify Libplacebo Source Code:

Locate src/gpu/utils.c in the libplacebo source.

Change the assertion:

c
// Original line (line 160):
assert(gpu->limits.max_vbo_size <= gpu->limits.max_buf_size);
// Modified line:
if (gpu->limits.max_vbo_size > gpu->limits.max_buf_size) {
gpu->limits.max_vbo_size = gpu->limits.max_buf_size;
}
Recompile MPV with the modified libplacebo. Use Meson/Ninja for building:

bash
git clone https://code.videolan.org/videolan/libplacebo.git
cd libplacebo

Apply the code change

meson setup build
ninja -C build
Replace the existing mpv-1.dll with the newly compiled version.

Use Direct3D 11 Instead of Vulkan
Problem: Vulkan backend triggers driver-specific crashes in Stremio’s environment.

Fix: Force MPV to use Direct3D 11:

In mpv.conf, add:

ini
vo=gpu-next
gpu-api=d3d11

Update AMD Drivers
Problem: Outdated drivers may misreport Vulkan capabilities.

Fix:

Download the latest AMD Adrenalin Edition drivers from AMD’s official site.

Ensure “Vulkan Support” is selected during installation.

Adjust Vulkan Parameters (If Sticking to Vulkan)
Problem: Vulkan buffer/queue settings may conflict with Stremio.

Fix: Add these to mpv.conf:

ini
vo=gpu-next
gpu-api=vulkan
vulkan-queue-count=1
vulkan-swap-mode=fifo

Test Older Libplacebo/MPV Builds
Problem: The issue might stem from a regression in newer libplacebo versions.

Fix: Use an MPV build linked against libplacebo v5.229.0 (or earlier). Prebuilt binaries can sometimes be found in mpv-winbuild-cmake https://github.com/shinchiro/mpv-winbuild-cmake/releases.

Additional Notes
Stremio Configuration:

Verify that Stremio’s patch for MPV config is correctly applied. Ensure no conflicting settings exist in mpv.conf or input.conf.

Debugging:

Capture a full crash dump using tools like WinDbg or ProcDump to analyze the ucrtbase.dll fault further.

Community Support:

Report the issue to libplacebo’s GitHub https://github.com/haasn/libplacebo/issues with details about the AMD driver version and Vulkan capabilities.