On Tue, Oct 26, 2021 at 5:41 PM Anup Patel <anup.pa...@wdc.com> wrote:
>
> The guest external interrupts from an interrupt controller are
> delivered only when the Guest/VM is running (i.e. V=1). This means
> any guest external interrupt which is triggered while the Guest/VM
> is not running (i.e. V=0) will be missed on QEMU resulting in Guest
> with sluggish response to serial console input and other I/O events.
>
> To solve this, we check and inject interrupt after setting V=1.
>
> Signed-off-by: Anup Patel <anup.pa...@wdc.com>
Reviewed-by: Alistair Francis <alistair.fran...@wdc.com>
Alistair
> ---
> target/riscv/cpu_helper.c | 13 +++++++++++++
> 1 file changed, 13 insertions(+)
>
> diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c
> index bb7ac9890b..04df3792a8 100644
> --- a/target/riscv/cpu_helper.c
> +++ b/target/riscv/cpu_helper.c
> @@ -287,6 +287,19 @@ void riscv_cpu_set_virt_enabled(CPURISCVState *env, bool
> enable)
> }
>
> env->virt = set_field(env->virt, VIRT_ONOFF, enable);
> +
> + if (enable) {
> + /*
> + * The guest external interrupts from an interrupt controller are
> + * delivered only when the Guest/VM is running (i.e. V=1). This means
> + * any guest external interrupt which is triggered while the Guest/VM
> + * is not running (i.e. V=0) will be missed on QEMU resulting in guest
> + * with sluggish response to serial console input and other I/O
> events.
> + *
> + * To solve this, we check and inject interrupt after setting V=1.
> + */
> + riscv_cpu_update_mip(env_archcpu(env), 0, 0);
> + }
> }
>
> bool riscv_cpu_force_hs_excep_enabled(CPURISCVState *env)
> --
> 2.25.1
>
>
