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However, that check is racy due to not >>> holding any locks at that time. >>> >>> Therefore, re-check the result after acquiring locks and bailing >>> if they no longer match. >>> >>> Additionally, clarify the not_move_group case from the >>> move_group-vs-move_group race. >> >> Tested-by: Ravi Bangoria >> >> Below is a quick test to reproduce the issue. It triggers WARN_ON() >> as normal user. No warnings with the patch. > > Shouldn't this test be in tools/perf/tests/ or so? The issue was because of multiple event contexts involved. However, it's no longer the case with reworked event context: https://git.kernel.org/tip/tip/c/bd27568117664b Thanks, Ravi