[lworld] RFR: 8368099: [lworld] Crash in frame::sender_for_compiled_frame while processing JFR sampling request

[Markus Grönlund]

On Mon, 22 Sep 2025 22:37:30 GMT, Patricio Chilano Mateo <pchilanomate at openjdk.org> wrote:

> Reconstructing a synthetic compiled frame when processing a sample request at a poll on return doesn’t work for frames that need stack repair. The stack walking code will read the frame size from the stack, but the memory has already been overwritten by the SafepointBlob frame. See comments in JBS issue for full details.
> 
> This patch skips the attempt to create this synthetic frame in case the frame needs stack repair. This fixes the crash but doesn't handle the safepoint bias issue. A more permanent solution will be required for that.
> 
> I tested the patch along the fix for 8368002 and verified that Jetty.java doesn’t crash anymore.
> 
> Thanks,
> Patricio

Looks good, but we need to revisit this properly.

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Marked as reviewed by mgronlun (no project role).

PR Review: https://git.openjdk.org/valhalla/pull/1610#pullrequestreview-3257390949