[PATCH v2 2/7] KVM: arm64: Support FFA_NOTIFICATION_BITMAP_DESTROY in host handler

[Sebastian Ene]

On Wed, Jun 10, 2026 at 09:53:24AM +0100, Vincent Donnefort wrote:
> On Mon, Jun 08, 2026 at 04:55:44PM +0000, Sebastian Ene wrote:
> > Allow FF-A notification bitmap destruction messages to be forwarded to
> > Trustzone from the host.
> > 
> > Signed-off-by: Sebastian Ene <sebastianene at google.com>
> > ---
> >  arch/arm64/kvm/hyp/nvhe/ffa.c | 24 +++++++++++++++++++++++-
> >  1 file changed, 23 insertions(+), 1 deletion(-)
> > 
> > diff --git a/arch/arm64/kvm/hyp/nvhe/ffa.c b/arch/arm64/kvm/hyp/nvhe/ffa.c
> > index c20d45191085..91e89d889c44 100644
> > --- a/arch/arm64/kvm/hyp/nvhe/ffa.c
> > +++ b/arch/arm64/kvm/hyp/nvhe/ffa.c
> > @@ -688,7 +688,6 @@ static bool ffa_call_supported(u64 func_id)
> >  	case FFA_MEM_DONATE:
> >  	case FFA_MEM_RETRIEVE_REQ:
> >         /* Optional notification interfaces added in FF-A 1.1 */
> > -	case FFA_NOTIFICATION_BITMAP_DESTROY:
> >  	case FFA_NOTIFICATION_BIND:
> >  	case FFA_NOTIFICATION_UNBIND:
> >  	case FFA_NOTIFICATION_SET:
> > @@ -893,6 +892,26 @@ static void do_ffa_notif_bitmap_create(struct arm_smccc_1_2_regs *res,
> >  	arm_smccc_1_2_smc(args, res);
> >  }
> >  
> > +static void do_ffa_notif_bitmap_destroy(struct arm_smccc_1_2_regs *res,
> > +					struct kvm_cpu_context *ctxt)
> > +{
> > +	DECLARE_REG(u32, vmid, ctxt, 1);
> > +	struct arm_smccc_1_2_regs *args;
> > +
> > +	if (ffa_check_unused_args_sbz(ctxt, 2)) {
> > +		ffa_to_smccc_res(res, FFA_RET_INVALID_PARAMETERS);
> > +		return;
> > +	}
> > +
> > +	if (vmid != HOST_FFA_ID) {
> > +		ffa_to_smccc_res(res, FFA_RET_INVALID_PARAMETERS);
> > +		return;
> > +	}
> > +
> > +	args = (void *)&ctxt->regs.regs[0];
> > +	arm_smccc_1_2_smc(args, res);
> > +}

Hello Vincent,

> 
> Sounds exactly like do_ffa_notif_bitmap_create. Could we use a single one
> "do_ffa_notif_bitmap" ? 
> 

Yes, I guess we can have only one method since the only difference
between them is in the number of unused args.

> > +
> >  bool kvm_host_ffa_handler(struct kvm_cpu_context *host_ctxt, u32 func_id)
> >  {
> >  	struct arm_smccc_1_2_regs res;
> > @@ -954,6 +973,9 @@ bool kvm_host_ffa_handler(struct kvm_cpu_context *host_ctxt, u32 func_id)
> >  	case FFA_NOTIFICATION_BITMAP_CREATE:
> >  		do_ffa_notif_bitmap_create(&res, host_ctxt);
> >  		goto out_handled;
> > +	case FFA_NOTIFICATION_BITMAP_DESTROY:
> > +		do_ffa_notif_bitmap_destroy(&res, host_ctxt);
> > +		goto out_handled;
> >  	}
> >  
> >  	if (ffa_call_supported(func_id))
> > -- 
> > 2.54.0.1064.gd145956f57-goog
> > 

Thanks,
Sebastian