Date:   Thu, 26 Jan 2023 20:20:54 +0000
From:   Oliver Upton <oliver.upton@linux.dev>
To:     Gavin Shan <gshan@redhat.com>
Cc:     kvmarm@lists.linux.dev, kvmarm@lists.cs.columbia.edu,
        kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-doc@vger.kernel.org, pbonzini@redhat.com, corbet@lwn.net,
        maz@kernel.org, will@kernel.org, ricarkol@google.com,
        eric.auger@redhat.com, yuzhe@nfschina.com, renzhengeek@gmail.com,
        reijiw@google.com, ardb@kernel.org, Julia.Lawall@inria.fr,
        yuzenghui@huawei.com, seanjc@google.com, shan.gavin@gmail.com
Subject: Re: [PATCH v2 1/3] KVM: arm64: Add helper vgic_write_guest_lock()
Message-ID: <Y9LgplvWZtdjXCEE@google.com>
References: <20230119234405.349644-1-gshan@redhat.com>
 <20230119234405.349644-2-gshan@redhat.com>
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Hi Gavin,

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@linux.dev>
> Signed-off-by: Gavin Shan <gshan@redhat.com>
> ---
>  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?

-- 
Thanks,
Oliver