Artem Savkov
ff271c4969
BugLink: https://bugs.launchpad.net/bugs/2060097 [ Upstream commit d177c1be06ce28aa8c8710ac55be1b5ad3f314c6 ] It is possible for bpf_kfunc_call_test_release() to be called from bpf_map_free_deferred() when bpf_testmod is already unloaded and perf_test_stuct.cnt which it tries to decrease is no longer in memory. This patch tries to fix the issue by waiting for all references to be dropped in bpf_testmod_exit(). The issue can be triggered by running 'test_progs -t map_kptr' in 6.5, but is obscured in 6.6 byd119357d07("rcu-tasks: Treat only synchronous grace periods urgently"). Fixes:65eb006d85("bpf: Move kernel test kfuncs to bpf_testmod") Signed-off-by: Artem Savkov <asavkov@redhat.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Yonghong Song <yonghong.song@linux.dev> Cc: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/bpf/82f55c0e-0ec8-4fe1-8d8c-b1de07558ad9@linux.dev Link: https://lore.kernel.org/bpf/20240110085737.8895-1-asavkov@redhat.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> (cherry picked from commit 20562df2d513ffe60678dd180cf90ae29469c28b) Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>