test(lmbench): track DragonOS blocking issues

[mistcoversmyeyes]

Goal

Track and fix DragonOS defects that block lmbench cases from completing correctly. Each blocking problem is tracked in a dedicated issue for reproduction, root-cause analysis, and fix verification.

Resolving these blockers will allow more lmbench cases to enter repeated DragonOS testing and provide the foundation for a stable performance baseline.

Existing issues

Issue	DragonOS problem	Investigation status
#2159	timer_create(CLOCK_REALTIME) returns EINVAL, affecting the POSIX timer path used by GNU timeout during lmbench execution.	The issue includes a guest C reproducer and identifies the unsupported clock ID. The warning alone does not imply benchmark failure, since timeout can fall back.
#2169	Fork-related hangs prevent lmbench cases and the full suite from completing reliably.	The issue contains reproduction records and GDB snapshots. The precise kernel root cause remains to be established; reproduce on the current revision before confirming the scheduler attribution.

Additional issues will be linked as further DragonOS blockers are reproduced and investigated. Each issue should include the affected cases, DragonOS revision and environment, reproduction steps, relevant diagnostic evidence, and fix verification. Evidence needed to understand a blocker should be available in the issue or a publicly accessible link.

Completion criteria

• Remaining DragonOS blockers have linked issues with reproducible evidence and a clear investigation status.
• Applicable linked blockers are resolved, with the affected cases verified both individually and within the lmbench suite on an identified DragonOS revision.
• Repeated DragonOS runs of the affected cases complete without the tracked hangs or failures, allowing those cases to proceed to stability testing and baseline collection.

Related work

• test(lmbench): 引入 lmbench 测试框架集成和自动测试脚本 #1433 — lmbench integration.