From: Emil Tsalapatis (Meta) <emil@xxxxxxxxxxxxxxx> In BPF programs, kfunc calls while holding a lock are not allowed because kfuncs may sleep by default. The exception to this rule are the functions in special_kfunc_list, which are guaranteed to not sleep. The bpf_iter_num_* functions used by the bpf_for and bpf_repeat macros make no function calls themselves, and as such are guaranteed to not sleep. Add them to special_kfunc_list to allow them within BPF spinlock critical sections. Signed-off-by: Emil Tsalapatis (Meta) <emil@xxxxxxxxxxxxxxx> Emil Tsalapatis (2): bpf: Allow bpf_for/bpf_repeat calls while holding a spinlock selftests/bpf: test bpf_for within spin lock section kernel/bpf/verifier.c | 20 +++++++++++++- .../selftests/bpf/progs/verifier_spin_lock.c | 26 +++++++++++++++++++ 2 files changed, 45 insertions(+), 1 deletion(-) -- 2.47.1
