Re: [PATCH v2 5/7] virt: geniezone: Add irqchip support for virtual interrupt injection

["Yi-De Wu (吳一德)" <Yi-De.Wu@mediatek.com>]

On Fri, 2023-04-28 at 19:59 +0100, Marc Zyngier wrote:
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> 
> On 2023-04-28 11:36, Yi-De Wu wrote:
> > From: "Yingshiuan Pan" <yingshiuan.pan@mediatek.com>
> > 
> > Enable GenieZone to handle virtual interrupt injection request.
> > 
> > Signed-off-by: Yingshiuan Pan <yingshiuan.pan@mediatek.com>
> > Signed-off-by: Yi-De Wu <yi-de.wu@mediatek.com>
> > ---
> >  arch/arm64/geniezone/Makefile       |  2 +-
> >  arch/arm64/geniezone/gzvm_arch.c    | 24 ++++++--
> >  arch/arm64/geniezone/gzvm_arch.h    | 11 ++++
> >  arch/arm64/geniezone/gzvm_irqchip.c | 88
> > +++++++++++++++++++++++++++++
> >  drivers/virt/geniezone/gzvm_vm.c    | 75 ++++++++++++++++++++++++
> >  include/linux/gzvm_drv.h            |  4 ++
> >  include/uapi/linux/gzvm.h           | 38 ++++++++++++-
> >  7 files changed, 235 insertions(+), 7 deletions(-)
> >  create mode 100644 arch/arm64/geniezone/gzvm_irqchip.c
> 
> [...]
> 
> > +++ b/arch/arm64/geniezone/gzvm_irqchip.c
> > @@ -0,0 +1,88 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Copyright (c) 2023 MediaTek Inc.
> > + */
> > +
> > +#include <linux/irqchip/arm-gic-v3.h>
> > +#include <kvm/arm_vgic.h>
> 
> NAK.
> 
> There is no way you can rely on anything from KVM in
> your own hypervisor code.
> 

Same with previous discussion, we'd like to copy or rename the related 
part from KVM and keep the maintainance at our own if it's ok.

> > +
> > +#include <linux/gzvm.h>
> > +#include <linux/gzvm_drv.h>
> > +#include "gzvm_arch.h"
> > +
> > +/**
> > + * gzvm_sync_vgic_state() - Check all LRs synced from gz
> > hypervisor
> > + *
> > + * Traverse all LRs, see if any EOIed vint, notify_acked_irq if
> > any.
> > + * GZ does not fold/unfold everytime KVM_RUN, so we have to
> > traverse
> > all saved
> > + * LRs. It will not takes much more time comparing to fold/unfold
> > everytime
> > + * GZVM_RUN, because there are only few LRs.
> > + */
> > +void gzvm_sync_vgic_state(struct gzvm_vcpu *vcpu)
> > +{
> > +}
> > +
> > +/* is_irq_valid() - Check the irq number and irq_type are matched
> > */
> > +static bool is_irq_valid(u32 irq, u32 irq_type)
> > +{
> > +     switch (irq_type) {
> > +     case GZVM_IRQ_TYPE_CPU:
> > +             /*  0 ~ 15: SGI */
> > +             if (likely(irq <= GZVM_IRQ_CPU_FIQ))
> > +                     return true;
> > +             break;
> > +     case GZVM_IRQ_TYPE_PPI:
> > +             /* 16 ~ 31: PPI */
> > +             if (likely(irq >= VGIC_NR_SGIS && irq <
> > VGIC_NR_PRIVATE_IRQS))
> 
> What happens if I redefine all these macros tomorrow? None of
> this code should rely on anything that is *INTERNAL* to KVM.
> 
>          M.
> --
> Jazz is not dead. It just smells funny...