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X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Song Liu , Daniel Borkmann , Paul Burton , paul.chaignon@gmail.com, Netdev , Alexei Starovoitov , linux-riscv@lists.infradead.org, Martin KaFai Lau , Yonghong Song , Mahshid Khezri , Andrii Nakryiko , bpf Sender: "linux-riscv" Errors-To: linux-riscv-bounces+infradead-linux-riscv=archiver.kernel.org@lists.infradead.org On Mon, 9 Dec 2019 at 20:57, Bj=C3=B6rn T=C3=B6pel = wrote: > > On Mon, 9 Dec 2019 at 19:52, Paul Chaignon wro= te: > > > > All BPF JIT compilers except RISC-V's and MIPS' enforce a 33-tail calls > > limit at runtime. In addition, a test was recently added, in tailcalls= 2, > > to check this limit. > > > > This patch updates the tail call limit in RISC-V's JIT compiler to allo= w > > 33 tail calls. I tested it using the above selftest on an emulated > > RISCV64. > > > > 33! ICK! ;-) Thanks for finding this! > > Acked-by: Bj=C3=B6rn T=C3=B6pel > ...and somewhat related; One of the tailcall tests fail due to missing far-branch support in the emitter. I'll address this in the v2 of the "far branch" series.