Re: [PATCH v7 05/12] arm/sve: save/restore SVE context switch

[Bertrand Marquis <Bertrand.Marquis@xxxxxxx>]

Hi Luca,

> On 23 May 2023, at 09:43, Luca Fancellu <Luca.Fancellu@xxxxxxx> wrote:
> 
> Save/restore context switch for SVE, allocate memory to contain
> the Z0-31 registers whose length is maximum 2048 bits each and
> FFR who can be maximum 256 bits, the allocated memory depends on
> how many bits is the vector length for the domain and how many bits
> are supported by the platform.
> 
> Save P0-15 whose length is maximum 256 bits each, in this case the
> memory used is from the fpregs field in struct vfp_state,
> because V0-31 are part of Z0-31 and this space would have been
> unused for SVE domain otherwise.
> 
> Create zcr_el{1,2} fields in arch_vcpu, initialise zcr_el2 on vcpu
> creation given the requested vector length and restore it on
> context switch, save/restore ZCR_EL1 value as well.
> 
> List import macros from Linux in README.LinuxPrimitives.
> 
> Signed-off-by: Luca Fancellu <luca.fancellu@xxxxxxx>
Reviewed-by: Bertrand Marquis <bertrand.marquis@xxxxxxx>

Just ...

> ---
> Changes from v6:
> - Add comment for explain why sve_save/sve_load are different from
>   Linux, add macros in xen/arch/arm/README.LinuxPrimitives (Julien)
> - Add comments in sve_context_init and sve_context_free, handle the
>   case where sve_zreg_ctx_end is NULL, move setting of v->arch.zcr_el2
>   in sve_context_init (Julien)
> - remove stubs for sve_context_* and sve_save_* and rely on compiler
>   DCE (Jan)
> - Add comments for sve_save_ctx/sve_load_ctx (Julien)
> Changes from v5:
> - use XFREE instead of xfree, keep the headers (Julien)
> - Avoid math computation for every save/restore, store the computation
>   in struct vfp_state once (Bertrand)
> - protect access to v->domain->arch.sve_vl inside arch_vcpu_create now
>   that sve_vl is available only on arm64
> Changes from v4:
> - No changes
> Changes from v3:
> - don't use fixed len types when not needed (Jan)
> - now VL is an encoded value, decode it before using.
> Changes from v2:
> - No changes
> Changes from v1:
> - No changes
> Changes from RFC:
> - Moved zcr_el2 field introduction in this patch, restore its
>   content inside sve_restore_state function. (Julien)
> 
> fix patch 5
> 
> Signed-off-by: Luca Fancellu <luca.fancellu@xxxxxxx>
> Change-Id: Ief65b2ff14fd579afa4fd110ce08a19980e64fa9

You have a signed off and a change-id that should not be here.
They are in the comment section so should be removed during push so might be ok 
:-)

Cheers
Bertrand