Ollama / Ollama

Ollama SIGSEGV Crash in MLX VAE Decode on M4 Pro macOS

Fix Ollama SIGSEGV crash during image generation VAE decode on Apple Silicon Includes evidence for Ollama troubleshooting demand.

Source-backed Last updated May 12, 2026 1 source Needs local verification

Category: Ollama
Error signature: SIGSEGV addr=0x0 during VAE decode after diffusion steps
Quick fix: Compare the failing environment with a known working setup, then change one configuration value at a time.
Updated: May 12, 2026
Verification status: Source-backed
Evidence: 1 public source URL

Before you change production

This page includes public source URLs in the imported troubleshooting record. Compare those references with your version and environment before applying changes.

Reproduce the smallest failing action and save non-secret logs before changing configuration.
Check versions for Ollama, related SDKs, package managers, CI runners, and hosting providers.
Change one setting or dependency at a time, then rerun the same failing command or request.
Avoid destructive commands, credential rotation, billing changes, or security relaxations without a rollback plan.

What this error means

SIGSEGV addr=0x0 during VAE decode after diffusion steps is a Ollama failure pattern reported for developers trying to fix ollama sigsegv crash during image generation vae decode on apple silicon. Based on the imported evidence, treat this as a tool-specific troubleshooting page rather than a generic API error.

Why this happens

Active GitHub issue on ollama/ollama (May 2026). x/z-image-turbo model completes 9/9 diffusion steps then crashes with SIGSEGV addr=0x0 during VAE decode on M4 Pro 64GB macOS 26.4.1 with Ollama 0.23.2. Logs show mlx runner subprocess termination after the crash.

Common causes

Ollama users running diffusion models on M-series Macs experience reproducible SIGSEGV crashes after all diffusion steps complete, during the VAE decode phase. The error message is opaque ('signal: segmentation fault') and developers need specific workarounds for MLX backend on macOS.
Active GitHub issue on ollama/ollama (May 2026). x/z-image-turbo model completes 9/9 diffusion steps then crashes with SIGSEGV addr=0x0 during VAE decode on M4 Pro 64GB macOS 26.4.1 with Ollama 0.23.2. Logs show mlx runner subprocess termination after the crash.

Quick fixes

Confirm the exact error signature matches SIGSEGV addr=0x0 during VAE decode after diffusion steps.
Check the Ollama account, local tool state, and provider configuration involved in the failing workflow.
Compare the failing environment with a known working setup, then change one configuration value at a time.

Platform/tool-specific checks

Verify the command, editor, extension, or API client that produced the error.
Compare local settings with CI, deployment, or editor-level settings when the error appears in only one environment.
Avoid deleting credentials, local model data, or project settings until the failing scope is clear.

Step-by-step troubleshooting

Capture the exact error message and the command, editor action, or request that triggered it.
Check whether the failure is account/auth, quota/rate, model/provider, local runtime, or deployment configuration.
Review the source evidence below and compare it with your environment.
Apply one change at a time and rerun the smallest failing action.
Keep the working fix documented for the team or deployment environment.

How to prevent it

Keep provider/tool configuration documented.
Record non-secret diagnostics such as tool version, provider name, model name, and command path.
Add a lightweight check before CI or production workflows depend on the tool.

Diagnostic flow for this page

Match SIGSEGV addr=0x0 during VAE decode after diffusion steps exactly before applying the quick fix.
Compare the failing environment with Ollama versions, account scope, provider settings, and deployment context.
Check the listed common causes in order, starting with the cause that best matches your logs.
Use the evidence status below to decide whether to confirm against public sources or official documentation.
Apply one reversible change, rerun the smallest failing action, and keep rollback notes.

FAQ

What does SIGSEGV addr=0x0 during VAE decode after diffusion steps mean in Ollama?

SIGSEGV addr=0x0 during VAE decode after diffusion steps indicates the workflow described by "Ollama SIGSEGV Crash in MLX VAE Decode on M4 Pro macOS" failed in a Ollama context. Start by confirming the exact signature and the component that emitted it.

What should I check first for SIGSEGV addr=0x0 during VAE decode after diffusion steps?

Check whether this cause matches your environment: Ollama users running diffusion models on M-series Macs experience reproducible SIGSEGV crashes after all diffusion steps complete, during the VAE decode phase. The error message is opaque ('signal: segmentation fault') and developers need specific workarounds for MLX backend on macOS.

Is the SIGSEGV addr=0x0 during VAE decode after diffusion steps guidance source-backed?

The "Ollama SIGSEGV Crash in MLX VAE Decode on M4 Pro macOS" page is labeled source-backed. It has 1 public source URL from github.com, so use that evidence status when deciding how much additional verification you need.

When should I avoid the quick fix for SIGSEGV addr=0x0 during VAE decode after diffusion steps?

For "Ollama SIGSEGV Crash in MLX VAE Decode on M4 Pro macOS", avoid applying "Compare the failing environment with a known working setup, then change one configuration value at a time." when the error text differs, the affected version or provider is different, or the change would touch credentials, billing, DNS, production deploy settings, or irreversible data.

What should I collect before debugging SIGSEGV addr=0x0 during VAE decode after diffusion steps?

For "Ollama SIGSEGV Crash in MLX VAE Decode on M4 Pro macOS", collect the failing Ollama command or request, non-secret configuration, versions, timestamps, request IDs when available, and the smallest reproduction that still triggers the signature.