Re: [PATCH v19 02/13] linux-user: Add LoongArch signal support

[maobibo]

在 2022/6/24 07:34, Richard Henderson 写道:
> On 6/23/22 01:55, Song Gao wrote:
>> +static void setup_sigcontext(CPULoongArchState *env,
>> +                             struct target_sigcontext *sc,
>> +                             struct extctx_layout *extctx)
>> +{
>> +    int i;
>> +
>> +    if (extctx->flags & SC_USED_FP) {
>> +        __put_user(extctx->fpu.addr, &sc->sc_extcontext[0]);
>> +    } else {
>> +        __put_user(extctx->end.addr, &sc->sc_extcontext[0]);
>> +    }
> 
> This is incorrect.  Where did this come from?  It certainly doesn't appear in 
> the kernel's version of setup_sigcontext.  The only reason the result works 
> for you is that this is overwritten by copy_fpu_to_sigframe within 
> setup_sigframe.

The val of flags is SC_USED_FP alway in function setup_extcontext in this 
version. We want to optimization in future if FP is not used for application 
where sigcontext for FP is not necessary. Also it can will be extended for 
128bit/256bit vector FPU. 

regards
bibo,mao
> 
> 
> r~