Pu Lehui <pulehui@xxxxxxxxxxxxxxx> writes: > BPF trampoline is the critical infrastructure of the bpf > subsystem, acting as a mediator between kernel functions > and BPF programs. Numerous important features, such as > using ebpf program for zero overhead kernel introspection, > rely on this key component. We can't wait to support bpf > trampoline on RV64. Since RV64 does not support ftrace > direct call yet, the current RV64 bpf trampoline is only > used in bpf context. > > As most of riscv cpu support unaligned memory accesses, > we temporarily use patch [1] to facilitate testing. The > test results are as follow, and test_verifier with no > new failure ceses. > > - fexit_bpf2bpf:OK > - dummy_st_ops:OK > - xdp_bpf2bpf:OK > > [1] https://lore.kernel.org/linux-riscv/20210916130855.4054926-2-chenhuang5@xxxxxxxxxx/ > > v1: > - Remove the logic of bpf_arch_text_poke supported for > kernel functions. (Kuohai and Björn) > - Extend patch_text for multiple instructions. (Björn) > - Fix OOB issue when image too big. (Björn) This series is ready to go in as is. @Palmer I'd like to take this series via the bpf-next tree (as usual), but note that there are some non-BPF changes as well, related to text poking. @Lehui I'd like to see two follow-up patches: 1. Enable kfunc for RV64, by adding: | bool bpf_jit_supports_kfunc_call(void) | { | return true; | } 2. Remove the checkpatch warning on patch 4: | WARNING: kfree(NULL) is safe and this check is probably not required | #313: FILE: arch/riscv/net/bpf_jit_comp64.c:984: | + if (branches_off) | + kfree(branches_off); For the series: Tested-by: Björn Töpel <bjorn@xxxxxxxxxxxx> Acked-by: Björn Töpel <bjorn@xxxxxxxxxxxx>
