Re: [PATCH v2 3/7] target/arm: Do not use aarch64_sve_zcr_get_valid_len in reset

[Richard Henderson]

On 5/19/22 03:40, Peter Maydell wrote:
> Not all the code that looks at the sve vector length
> goes through sve_zcr_len_for_el(), though. In particular,
> this is setting up ZCR_EL1 for usermode, and all
> the code under linux-user/ that wants to know the vector
> length does it with "env->vfp.zcr_el[1] & 0xf".

Oops, yes.  Linux-user should be checking ZCR_LEN from env->hflags.

> Incidentally, do_prctl_set_vl() also sets zcr_el[1] and
> it doesn't call aarch64_sve_zcr_get_valid_len(). Should it,
> or is it doing an equivalent check anyway?

I think this got missed when we introduced the set of valid lengths -- it's still assuming 
all lengths less than maximum are valid.

I'll add a couple of cleanup patches for this.

r~