Threadgroup1 leads to memory leak

[eternalNight]

Description

In the unit test threadgroup1, the test sometimes (but not always) end with memory leak.

Commit

5d1fdc2 Mark threadgroup1 as a known failure on i386 and amd64

Reproduce Steps

cd ucore
make ARCH=i386 defconfig
UCORE_TEST=/testbin/threadgroup1 make kernel
UCORE_TEST=/testbin/threadgroup1 make sfsimg
./uCore_test -f src/user-ucore/testspecs/threadgroup1.testspec

Current Result

The unit test fail with

!! error: missing 'init check memory pass.'

Expected Result

Init check memory should pass.