All helpers from this file can trigger ILLEGAL_INSN exceptions via check_zicbo_envcfg() directly, bypassing the usual exception code from translate.c. If we don't save the opcode before each helper, riscv_raise_exception() is triggered and env->bins won't be unwind during cpu_loop_exit_restore() (code path cpu_restore_state -> cpu_restore_state_from_tb() -> restore_state_to_opc()).
And finally, in riscv_cpu_do_interrupt(), we will set (m)tval = 0 when we can, instead, set it to the cbo opcode that generated the exception. Resolves: https://gitlab.com/qemu-project/qemu/-/work_items/3380 Signed-off-by: Daniel Henrique Barboza <[email protected]> --- target/riscv/insn_trans/trans_rvzicbo.c.inc | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/target/riscv/insn_trans/trans_rvzicbo.c.inc b/target/riscv/insn_trans/trans_rvzicbo.c.inc index 15711c3140..096f7dde27 100644 --- a/target/riscv/insn_trans/trans_rvzicbo.c.inc +++ b/target/riscv/insn_trans/trans_rvzicbo.c.inc @@ -33,6 +33,8 @@ static bool trans_cbo_clean(DisasContext *ctx, arg_cbo_clean *a) REQUIRE_ZICBOM(ctx); TCGv src = get_address(ctx, a->rs1, 0); + /* The helper may raise ILLEGAL_INSN -- record binv for unwind. */ + decode_save_opc(ctx, 0); gen_helper_cbo_clean_flush(tcg_env, src); return true; } @@ -42,6 +44,8 @@ static bool trans_cbo_flush(DisasContext *ctx, arg_cbo_flush *a) REQUIRE_ZICBOM(ctx); TCGv src = get_address(ctx, a->rs1, 0); + /* The helper may raise ILLEGAL_INSN -- record binv for unwind. */ + decode_save_opc(ctx, 0); gen_helper_cbo_clean_flush(tcg_env, src); return true; } @@ -51,6 +55,8 @@ static bool trans_cbo_inval(DisasContext *ctx, arg_cbo_inval *a) REQUIRE_ZICBOM(ctx); TCGv src = get_address(ctx, a->rs1, 0); + /* The helper may raise ILLEGAL_INSN -- record binv for unwind. */ + decode_save_opc(ctx, 0); gen_helper_cbo_inval(tcg_env, src); return true; } @@ -60,6 +66,8 @@ static bool trans_cbo_zero(DisasContext *ctx, arg_cbo_zero *a) REQUIRE_ZICBOZ(ctx); TCGv src = get_address(ctx, a->rs1, 0); + /* The helper may raise ILLEGAL_INSN -- record binv for unwind. */ + decode_save_opc(ctx, 0); gen_helper_cbo_zero(tcg_env, src); return true; } -- 2.43.0
