Re: [PATCH v12] xen/arm64: io: Handle data abort due to cache maintenance instructions

[Julien Grall <julien@xxxxxxx>]

Hi Ayan,

On 24/03/2022 13:37, Ayan Kumar Halder wrote:
>       /*
>        * At this point, we know that the instruction is either valid or has been
>        * decoded successfully. Thus, Xen should be allowed to execute the
> diff --git a/xen/arch/arm/ioreq.c b/xen/arch/arm/ioreq.c
> index 54167aebcb..87a6240f2a 100644
> --- a/xen/arch/arm/ioreq.c
> +++ b/xen/arch/arm/ioreq.c
> @@ -47,7 +47,7 @@ enum io_state try_fwd_ioserv(struct cpu_user_regs *regs,
>                                struct vcpu *v, mmio_info_t *info)
>   {
>       struct vcpu_io *vio = &v->io;
> -    struct instr_details instr = info->dabt_instr;
> +    const struct instr_details instr = info->dabt_instr;
>       struct hsr_dabt dabt = info->dabt;
>       ioreq_t p = {
>           .type = IOREQ_TYPE_COPY,
> @@ -62,7 +62,6 @@ enum io_state try_fwd_ioserv(struct cpu_user_regs *regs,
>            * memory access. So for now, we can safely always set to 0.
>            */
>           .df = 0,
> -        .data = get_user_reg(regs, info->dabt.reg),
>           .state = STATE_IOREQ_READY,
>       };
>       struct ioreq_server *s = NULL;
> @@ -74,12 +73,23 @@ enum io_state try_fwd_ioserv(struct cpu_user_regs *regs,
>           return IO_ABORT;
>       }
>   
> +    if ( instr.state == INSTR_CACHE )
> +        p.size = dcache_line_bytes;
I think it would be best to only set the p.size when instr.state != 
INSTR_CACHE in the else here.
I can do that on commit. I will also give a chance to Stefano to reply.

Cheers,

--
Julien Grall