Re: [PATCH v2 1/3] KVM: arm64: Add helper vgic_write_guest_lock()

[Gavin Shan]

Hi Oliver,

On 1/27/23 7:20 AM, Oliver Upton wrote:
> On Fri, Jan 20, 2023 at 07:44:03AM +0800, Gavin Shan wrote:
> > Currently, the unknown no-running-vcpu sites are reported when a
> > dirty page is tracked by mark_page_dirty_in_slot(). Until now, the
> > only known no-running-vcpu site is saving vgic/its tables through
> > KVM_DEV_ARM_{VGIC_GRP_CTRL, ITS_SAVE_TABLES} command on KVM device
> > "kvm-arm-vgic-its". Unfortunately, there are more unknown sites to
> > be handled and no-running-vcpu context will be allowed in these
> > sites: (1) KVM_DEV_ARM_{VGIC_GRP_CTRL, ITS_RESTORE_TABLES} command
> > on KVM device "kvm-arm-vgic-its" to restore vgic/its tables. The
> > vgic3 LPI pending status could be restored. (2) Save vgic3 pending
> > table through KVM_DEV_ARM_{VGIC_GRP_CTRL, VGIC_SAVE_PENDING_TABLES}
> > command on KVM device "kvm-arm-vgic-v3".
> >
> > In order to handle those unknown cases, we need a unified helper
> > vgic_write_guest_lock(). struct vgic_dist::save_its_tables_in_progress
> > is also renamed to struct vgic_dist::save_tables_in_progress. Besides,
> > "asm/kvm_mmu.h" needs to be included for "vgic.h" for the definition
> > of kvm_write_guest_lock().
> >
> > No functional change intended.
> >
> > Suggested-by: Oliver Upton <oliver.upton@xxxxxxxxx>
> > Signed-off-by: Gavin Shan <gshan@xxxxxxxxxx>
> > ---
> >   arch/arm64/kvm/vgic-sys-reg-v3.c   |  1 +
> >   arch/arm64/kvm/vgic/vgic-irqfd.c   |  1 +
> >   arch/arm64/kvm/vgic/vgic-its.c     | 13 +++++--------
> >   arch/arm64/kvm/vgic/vgic-mmio-v2.c |  1 +
> >   arch/arm64/kvm/vgic/vgic-mmio.c    |  1 +
> >   arch/arm64/kvm/vgic/vgic-v4.c      |  1 +
> >   arch/arm64/kvm/vgic/vgic.c         |  1 +
> >   arch/arm64/kvm/vgic/vgic.h         | 13 +++++++++++++
> >   include/kvm/arm_vgic.h             |  2 +-
> >   9 files changed, 25 insertions(+), 9 deletions(-)
>
> You wouldn't have to add the include all around the shop if you instead
> just stuck it in vgic.h...
>
> Having said that, we really ought to get a fix in for this sooner rather
> than later. I just hit it myself testing kvmarm/next.
>
> Marc, could you take care of the include fix when applying?

I've posted v3 to have a separate PATCH[1/4] where the header file inclusions
are handled, to save Marc's valuable time. After 'kvm_mmu.h' is included to
'vgic.h', the duplicate inclusions of 'kvm_mmu.h' needs to be removed. A separate
patch would make the follow-up patches clean.

https://lore.kernel.org/kvmarm/20230126235451.469087-1-gshan@xxxxxxxxxx/T/#t

Thanks,
Gavin