Re: [PATCH] target/riscv: Fix itrigger when icount is used

[liweiwei]

On 2023/3/24 14:40, LIU Zhiwei wrote:

When I boot a ubuntu image, QEMU output a "Bad icount read" message and exit.
The reason is that when execute helper_mret or helper_sret, it will
cause a call to icount_get_raw_locked (), which needs set can_do_io flag
on cpustate.

Thus we setting this flag when execute these two instructions.

Signed-off-by: LIU Zhiwei <zhiwei_...@linux.alibaba.com>
---

LGTM.

Reviewed-by: Weiwei Li <liwei...@iscas.ac.cn>

Weiwei L

  target/riscv/insn_trans/trans_privileged.c.inc | 6 ++++++
  1 file changed, 6 insertions(+)

diff --git a/target/riscv/insn_trans/trans_privileged.c.inc 
b/target/riscv/insn_trans/trans_privileged.c.inc
index 59501b2780..e3bee971c6 100644
--- a/target/riscv/insn_trans/trans_privileged.c.inc
+++ b/target/riscv/insn_trans/trans_privileged.c.inc
@@ -77,6 +77,9 @@ static bool trans_sret(DisasContext *ctx, arg_sret *a)
  #ifndef CONFIG_USER_ONLY
      if (has_ext(ctx, RVS)) {
          decode_save_opc(ctx);
+        if (tb_cflags(ctx->base.tb) & CF_USE_ICOUNT) {
+            gen_io_start();
+        }
          gen_helper_sret(cpu_pc, cpu_env);
          exit_tb(ctx); /* no chaining */
          ctx->base.is_jmp = DISAS_NORETURN;
@@ -93,6 +96,9 @@ static bool trans_mret(DisasContext *ctx, arg_mret *a)
  {
  #ifndef CONFIG_USER_ONLY
      decode_save_opc(ctx);
+    if (tb_cflags(ctx->base.tb) & CF_USE_ICOUNT) {
+        gen_io_start();
+    }
      gen_helper_mret(cpu_pc, cpu_env);
      exit_tb(ctx); /* no chaining */
      ctx->base.is_jmp = DISAS_NORETURN;