From 10541b374aa05c8118cc6a529a615882e53f261b Mon Sep 17 00:00:00 2001 From: Xu Kuohai Date: Tue, 16 Apr 2024 14:42:08 +0800 Subject: [PATCH] riscv, bpf: Fix incorrect runtime stats MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When __bpf_prog_enter() returns zero, the s1 register is not set to zero, resulting in incorrect runtime stats. Fix it by setting s1 immediately upon the return of __bpf_prog_enter(). Fixes: 49b5e77ae3e2 ("riscv, bpf: Add bpf trampoline support for RV64") Signed-off-by: Xu Kuohai Signed-off-by: Daniel Borkmann Reviewed-by: Pu Lehui Acked-by: Björn Töpel Link: https://lore.kernel.org/bpf/20240416064208.2919073-3-xukuohai@huaweicloud.com --- arch/riscv/net/bpf_jit_comp64.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/riscv/net/bpf_jit_comp64.c b/arch/riscv/net/bpf_jit_comp64.c index 1adf2f39ce59..ec9d692838fc 100644 --- a/arch/riscv/net/bpf_jit_comp64.c +++ b/arch/riscv/net/bpf_jit_comp64.c @@ -722,6 +722,9 @@ static int invoke_bpf_prog(struct bpf_tramp_link *l, int args_off, int retval_of if (ret) return ret; + /* store prog start time */ + emit_mv(RV_REG_S1, RV_REG_A0, ctx); + /* if (__bpf_prog_enter(prog) == 0) * goto skip_exec_of_prog; */ @@ -729,9 +732,6 @@ static int invoke_bpf_prog(struct bpf_tramp_link *l, int args_off, int retval_of /* nop reserved for conditional jump */ emit(rv_nop(), ctx); - /* store prog start time */ - emit_mv(RV_REG_S1, RV_REG_A0, ctx); - /* arg1: &args_off */ emit_addi(RV_REG_A0, RV_REG_FP, -args_off, ctx); if (!p->jited)