Help to debug issue on Debian riscv64

Environment

Ruby 3.1
Rails 6.1.7
Devise 4.8.1

Current behavior

Hi, sorry for the noise. Now we noticed the ruby-devise has trouble to pass Debian CI, it is also called autopkgtest. In short, debci is a platform to run tests on real hardware/machines.

The test cases from ruby-devise run well like others arch, but when to end/remove the debci env, unfortunately, we got error:

autopkgtest [19:01:05]: test smoke-test: -----------------------]
autopkgtest [19:01:05]: test smoke-test:  - - - - - - - - - - results - - - - - - - - - -
smoke-test           PASS
autopkgtest [19:01:26]: ERROR: "rm -rf /tmp/autopkgtest-lxc.6zr03xp5/downtmp/smoke-test-artifacts /tmp/autopkgtest-lxc.6zr03xp5/downtmp/autopkgtest_tmp" failed with stderr "rm: cannot remove '/tmp/autopkgtest-lxc.6zr03xp5/downtmp/autopkgtest_tmp/myapp/tmp/cache/bootsnap/compile-cache-iseq': Directory not empty
"

There is debci testing env on riscv64 like tmp/autopkgtest-lxc.6zr03xp5, So when we finished the debci test, the autopkgtest will remove debci's env. But there is very odd for autopkgtest_tmp dir can not be removed.

I compared the successful debci log from runtime on the amd64, There is indeed an extra directory on riscv64：

root@autopkgtest-lxc-wlpedb:/tmp/autopkgtest-lxc.lx9srso7/downtmp/build.434/real-tree#  ls ../../autopkgtest_tmp/myapp/tmp/cache/bootsnap/compile-cache-iseq/b5/
2455131736f1e6

I do not understand what means for b5 dir here, but by using hexdump to display it, we get the content: https://paste.debian.net/1274889/

I suspect the riscv64 host's environment affects here. In addition, I think the error hit about directory not empty due to deny permission to remove sub dir.

Thanks for any help here.

heartcombo / devise

Help to debug issue on Debian riscv64 #5574

Environment

Current behavior