Remote-SSH: cursor-server segfault on Ubuntu 22.04 VM (node server-main.js), VS Code works fine

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Hey, thanks for the detailed report. Everything’s written up exactly the way we need.

This is a known bug on our side, not a misconfig. The root cause is that the remote cursor-server is still running on Node v20. Its V8 can crash with SEGV_PKUERR on VMs where the CPU advertises Intel Memory Protection Keys (PKU), but the hypervisor doesn’t fully virtualize them. VS Code doesn’t crash on the same host because it uses Node 22, which handles missing PKU correctly. Your Xeon Silver 4510 in a VM is exactly this scenario.

Workaround: edit the server startup script on the remote host:

~/.cursor-server/bin/linux-x64/<commit>/bin/cursor-server

and add this right before the last line:

export NODE_OPTIONS="--no-node-snapshot --jitless"

Two important notes:

  • --jitless disables the V8 JIT, so latency will be higher.
  • This change gets overwritten on every server update, so you’ll need to reapply it.

The same workaround is confirmed in a similar thread: Remote SSH: Segmentation fault (SEGV_PKUERR) on CPUs without PKU support

We know about the bug and it’s been reported internally, but there’s no fix timeline yet. I’ll post an update here as soon as we have one.