Add a test to detect races between munmap() and creating new threads.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-Id: <20221028124227.2354792-3-iii@linux.ibm.com>
[rth: add more return insns]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Ilya Leoshkevich