From: marc.zyngier@arm.com (Marc Zyngier)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH v3 36/55] KVM: arm/arm64: vgic-new: Add GICv3 IROUTER register handlers
Date: Thu, 12 May 2016 13:37:57 +0100 [thread overview]
Message-ID: <57347925.2030902@arm.com> (raw)
In-Reply-To: <20160512122119.GH27623@cbox>
On 12/05/16 13:21, Christoffer Dall wrote:
> On Fri, May 06, 2016 at 11:45:49AM +0100, Andre Przywara wrote:
>> Since GICv3 supports much more than the 8 CPUs the GICv2 ITARGETSR
>> register can handle, the new IROUTER register covers the whole range
>> of possible target (V)CPUs by using the same MPIDR that the cores
>> report themselves.
>> In addition to translating this MPIDR into a vcpu pointer we store
>> the originally written value as well. The architecture allows to
>> write any values into the register, which must be read back as written.
>>
>> Since we don't support affinity level 3, we don't need to take care
>> about the upper word of this 64-bit register, which simplifies the
>> handling a bit.
>>
>> Signed-off-by: Andre Przywara <andre.przywara@arm.com>
>> ---
>> Changelog RFC..v1:
>> - fold in and simplify vgic_v3_irq_change_affinity
>>
>> Changelog v1 .. v2:
>> - adapt to new MMIO framework
>>
>> virt/kvm/arm/vgic/vgic-mmio-v3.c | 65 +++++++++++++++++++++++++++++++++++++++-
>> 1 file changed, 64 insertions(+), 1 deletion(-)
>>
>> diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c
>> index 48fba9c..3bcc2c4 100644
>> --- a/virt/kvm/arm/vgic/vgic-mmio-v3.c
>> +++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c
>> @@ -86,6 +86,69 @@ static u32 compress_mpidr(unsigned long mpidr)
>> return ret;
>> }
>>
>> +static unsigned long decompress_mpidr(u32 value)
>> +{
>> + unsigned long mpidr;
>> +
>> + mpidr = ((value >> 0) & 0xFF) << MPIDR_LEVEL_SHIFT(0);
>> + mpidr |= ((value >> 8) & 0xFF) << MPIDR_LEVEL_SHIFT(1);
>> + mpidr |= ((value >> 16) & 0xFF) << MPIDR_LEVEL_SHIFT(2);
>> + mpidr |= (u64)((value >> 24) & 0xFF) << MPIDR_LEVEL_SHIFT(3);
>> +
>> + return mpidr;
>> +}
>> +
>> +static unsigned long vgic_mmio_read_irouter(struct kvm_vcpu *vcpu,
>> + gpa_t addr, unsigned int len)
>> +{
>> + int intid = (addr & 0x1fff) / 8;
>> + struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, NULL, intid);
>> + unsigned long mpidr;
>> +
>> + if (!irq)
>> + return 0;
>> +
>> + mpidr = decompress_mpidr(irq->mpidr);
>
> I'm unsure here; do we ned a READ_ONCE() in lieu taking the lock or are
> we guaranteed that this is a single memory access even with compiler
> inlining etc.?
I can't imagine the compiler being stupid enough to read this multiple
times, but better safe than sorry. +1 for READ_ONCE().
>
>> + return extract_bytes(mpidr, addr & 7, len);
>> +}
>> +
>> +static void vgic_mmio_write_irouter(struct kvm_vcpu *vcpu,
>> + gpa_t addr, unsigned int len,
>> + unsigned long val)
>> +{
>> + int intid = (addr & 0x1fff) / 8;
>> + struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, NULL, intid);
>> + unsigned long mask = 0xffffffff; /* upper word is WI */
>> + u64 mpidr;
>> +
>> + if (!irq)
>> + return;
>> +
>> + /*
>> + * There are only two supported options:
>> + * (1) aligned 64-bit access
>> + * (2) aligned 32-bit access
>> + *
>> + * TODO: make this check generic and move it to dispatch_...()
>> + */
>> + if (len != 4 && len != 8)
>> + return;
>> +
>> +
>> + /* The upper word is WI for us since we don't implement Aff3. */
>> + if (addr & 4)
>> + return;
>> +
>> + spin_lock(&irq->irq_lock);
>> +
>> + mpidr = decompress_mpidr(irq->mpidr);
>> + mpidr = (mpidr & ~mask) | (val & mask);
>> + irq->mpidr = compress_mpidr(mpidr);
>> + irq->target_vcpu = kvm_mpidr_to_vcpu(vcpu->kvm, mpidr);
>
> this is weird because it doesn't preserve read-as-written semantics but
> allows a guest to write something into the RES0 field and read that back
> in the Aff3 field...
I don't see how we get this RES0/Aff3 mixup, but I can see other issues:
>> + unsigned long mask = 0xffffffff; /* upper word is WI */
followed by:
>> + mpidr = (mpidr & ~mask) | (val & mask);
is not going to preserve the top bits on 32bit (assuming we could
perform a 64bit access on 32bit, but still). Also, the mask preserves
the IRM bit, which is wrong (we don't support 1-of-n distribution).
Why don't we just have
mpidr = val & GENMASK_ULL(23, 0);
and let's be done with it? I must be missing something about this whole
Aff3 thing...
Thanks,
M.
--
Jazz is not dead. It just smells funny...
next prev parent reply other threads:[~2016-05-12 12:37 UTC|newest]
Thread overview: 200+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-05-06 10:45 [PATCH v3 00/55] KVM: arm/arm64: Rework virtual GIC emulation Andre Przywara
2016-05-06 10:45 ` [PATCH v3 01/55] KVM: arm/arm64: vgic: streamline vgic_update_irq_pending() interface Andre Przywara
2016-05-06 10:45 ` [PATCH v3 02/55] KVM: arm/arm64: vgic: avoid map in kvm_vgic_inject_mapped_irq() Andre Przywara
2016-05-06 10:45 ` [PATCH v3 03/55] KVM: arm/arm64: vgic: avoid map in kvm_vgic_map_is_active() Andre Przywara
2016-05-06 10:45 ` [PATCH v3 04/55] KVM: arm/arm64: vgic: avoid map in kvm_vgic_unmap_phys_irq() Andre Przywara
2016-05-06 10:45 ` [PATCH v3 05/55] KVM: arm/arm64: Remove the IRQ field from struct irq_phys_map Andre Przywara
2016-05-06 10:45 ` [PATCH v3 06/55] KVM: arm/arm64: arch_timer: Remove irq_phys_map Andre Przywara
2016-05-10 8:33 ` Eric Auger
2016-05-06 10:45 ` [PATCH v3 07/55] KVM: arm/arm64: vgic: Remove irq_phys_map from interface Andre Przywara
2016-05-06 10:45 ` [PATCH v3 08/55] KVM: arm/arm64: Get rid of vgic_cpu->nr_lr Andre Przywara
2016-05-18 10:43 ` Andre Przywara
2016-05-06 10:45 ` [PATCH v3 09/55] KVM: arm/arm64: Fix MMIO emulation data handling Andre Przywara
2016-05-10 8:57 ` Marc Zyngier
2016-05-18 11:02 ` Andre Przywara
2016-05-06 10:45 ` [PATCH v3 10/55] KVM: arm/arm64: Export mmio_read/write_bus Andre Przywara
2016-05-10 8:59 ` Marc Zyngier
2016-05-18 14:18 ` Andre Przywara
2016-05-06 10:45 ` [PATCH v3 11/55] KVM: arm/arm64: pmu: abstract access to number of SPIs Andre Przywara
2016-05-10 9:00 ` Marc Zyngier
2016-05-10 9:52 ` Eric Auger
2016-05-10 10:04 ` Marc Zyngier
2016-05-10 14:35 ` [PATCH v3a] " Andre Przywara
2016-05-10 14:58 ` Andrew Jones
2016-05-11 13:52 ` Andre Przywara
2016-05-10 15:22 ` Marc Zyngier
2016-05-06 10:45 ` [PATCH v3 12/55] KVM: arm/arm64: move GICv2 emulation defines into arm-gic-v3.h Andre Przywara
2016-05-10 9:02 ` Marc Zyngier
2016-05-06 10:45 ` [PATCH v3 13/55] KVM: arm/arm64: vgic-new: Add data structure definitions Andre Przywara
2016-05-10 9:05 ` Marc Zyngier
2016-05-12 12:12 ` Christoffer Dall
2016-05-12 12:17 ` Marc Zyngier
2016-05-12 12:23 ` Christoffer Dall
2016-05-12 13:25 ` Andre Przywara
2016-05-12 13:48 ` Christoffer Dall
2016-05-06 10:45 ` [PATCH v3 14/55] KVM: arm/arm64: vgic-new: Add acccessor to new struct vgic_irq instance Andre Przywara
2016-05-10 9:22 ` Marc Zyngier
2016-05-11 9:20 ` Andre Przywara
2016-05-10 9:35 ` Eric Auger
2016-05-06 10:45 ` [PATCH v3 15/55] KVM: arm/arm64: vgic-new: Implement virtual IRQ injection Andre Przywara
2016-05-10 9:25 ` Eric Auger
2016-05-10 9:39 ` Marc Zyngier
2016-05-10 12:08 ` Christoffer Dall
2016-05-06 10:45 ` [PATCH v3 16/55] KVM: arm/arm64: vgic-new: Add IRQ sorting Andre Przywara
2016-05-10 9:29 ` Eric Auger
2016-05-10 9:48 ` Marc Zyngier
2016-05-06 10:45 ` [PATCH v3 17/55] KVM: arm/arm64: vgic-new: Add IRQ sync/flush framework Andre Przywara
2016-05-10 13:11 ` Christoffer Dall
2016-05-10 13:53 ` Eric Auger
2016-05-10 15:20 ` Eric Auger
2016-05-10 17:32 ` Marc Zyngier
2016-05-12 11:46 ` Christoffer Dall
2016-05-12 15:08 ` Andre Przywara
2016-05-06 10:45 ` [PATCH v3 18/55] KVM: arm/arm64: vgic-new: Add GICv2 world switch backend Andre Przywara
2016-05-10 13:30 ` Christoffer Dall
2016-05-10 13:42 ` Marc Zyngier
2016-05-10 13:49 ` Eric Auger
2016-05-10 14:11 ` Christoffer Dall
2016-05-10 14:35 ` Marc Zyngier
2016-05-10 14:45 ` Marc Zyngier
2016-05-11 9:38 ` Christoffer Dall
2016-05-10 14:10 ` Eric Auger
2016-05-11 11:30 ` Andre Przywara
2016-05-11 11:38 ` Eric Auger
2016-05-11 13:09 ` Andre Przywara
2016-05-11 12:26 ` Christoffer Dall
2016-05-11 13:13 ` Andre Przywara
2016-05-06 10:45 ` [PATCH v3 19/55] KVM: arm/arm64: vgic-new: Add GICv3 " Andre Przywara
2016-05-06 19:07 ` Tom Hanson
2016-05-10 14:04 ` Christoffer Dall
2016-05-10 14:15 ` Peter Maydell
2016-05-10 14:22 ` Marc Zyngier
2016-05-11 9:39 ` Christoffer Dall
2016-05-10 15:28 ` Eric Auger
2016-05-10 17:35 ` Marc Zyngier
2016-05-06 10:45 ` [PATCH v3 20/55] KVM: arm/arm64: vgic-new: Implement kvm_vgic_vcpu_pending_irq Andre Przywara
2016-05-10 10:22 ` Marc Zyngier
2016-05-10 14:18 ` Christoffer Dall
2016-05-06 10:45 ` [PATCH v3 21/55] KVM: arm/arm64: vgic-new: Add MMIO handling framework Andre Przywara
2016-05-11 9:46 ` Christoffer Dall
2016-05-06 10:45 ` [PATCH v3 22/55] KVM: arm/arm64: vgic-new: Add GICv2 " Andre Przywara
2016-05-11 9:50 ` Christoffer Dall
2016-05-06 10:45 ` [PATCH v3 23/55] KVM: arm/arm64: vgic-new: Add CTLR, TYPER and IIDR handlers Andre Przywara
2016-05-11 12:05 ` Christoffer Dall
2016-05-11 12:47 ` Andre Przywara
2016-05-11 12:51 ` Marc Zyngier
2016-05-11 13:15 ` Christoffer Dall
2016-05-11 13:27 ` Marc Zyngier
2016-05-11 13:36 ` Andre Przywara
2016-05-11 14:40 ` Marc Zyngier
2016-05-11 13:38 ` Christoffer Dall
2016-05-06 10:45 ` [PATCH v3 24/55] KVM: arm/arm64: vgic-new: Add ENABLE registers handlers Andre Przywara
2016-05-10 10:28 ` Marc Zyngier
2016-05-11 12:34 ` Christoffer Dall
2016-05-11 13:04 ` Andre Przywara
2016-05-11 13:14 ` Christoffer Dall
2016-05-11 13:24 ` Andre Przywara
2016-05-11 13:41 ` Christoffer Dall
2016-05-11 13:16 ` Christoffer Dall
2016-05-11 13:13 ` Marc Zyngier
2016-05-11 13:39 ` Andre Przywara
2016-05-11 14:26 ` Marc Zyngier
2016-05-11 13:47 ` Christoffer Dall
2016-05-11 14:18 ` Andre Przywara
2016-05-11 14:28 ` Andre Przywara
2016-05-06 10:45 ` [PATCH v3 25/55] KVM: arm/arm64: vgic-new: Add PENDING " Andre Przywara
2016-05-10 10:49 ` Marc Zyngier
2016-05-11 13:11 ` Christoffer Dall
2016-05-06 10:45 ` [PATCH v3 26/55] KVM: arm/arm64: vgic-new: Add ACTIVE " Andre Przywara
2016-05-10 12:09 ` Christoffer Dall
2016-05-10 12:14 ` Marc Zyngier
2016-05-10 13:04 ` Andre Przywara
2016-05-10 13:12 ` Christoffer Dall
2016-05-06 10:45 ` [PATCH v3 27/55] KVM: arm/arm64: vgic-new: Add PRIORITY " Andre Przywara
2016-05-11 13:37 ` Christoffer Dall
2016-05-12 9:10 ` Marc Zyngier
2016-05-12 9:56 ` Peter Maydell
2016-05-12 10:09 ` Marc Zyngier
2016-05-06 10:45 ` [PATCH v3 28/55] KVM: arm/arm64: vgic-new: Add CONFIG " Andre Przywara
2016-05-12 8:32 ` Christoffer Dall
2016-05-06 10:45 ` [PATCH v3 29/55] KVM: arm/arm64: vgic-new: Add TARGET " Andre Przywara
2016-05-12 8:35 ` Christoffer Dall
2016-05-12 8:39 ` Marc Zyngier
2016-05-12 8:54 ` Christoffer Dall
2016-05-06 10:45 ` [PATCH v3 30/55] KVM: arm/arm64: vgic-new: Add SGIR register handler Andre Przywara
2016-05-12 8:40 ` Christoffer Dall
2016-05-06 10:45 ` [PATCH v3 31/55] KVM: arm/arm64: vgic-new: Add SGIPENDR register handlers Andre Przywara
2016-05-12 9:09 ` Christoffer Dall
2016-05-06 10:45 ` [PATCH v3 32/55] KVM: arm/arm64: vgic-new: Add GICv3 MMIO handling framework Andre Przywara
2016-05-09 17:18 ` Marc Zyngier
2016-05-09 17:51 ` Chalamarla, Tirumalesh
2016-05-10 10:58 ` [PATCH] KVM: arm/arm64: vgic-new: fix overlap check for device addresses Andre Przywara
2016-05-10 13:16 ` Marc Zyngier
2016-05-10 17:18 ` [PATCH v2] " Andre Przywara
2016-05-12 19:43 ` Christoffer Dall
2016-05-12 10:26 ` [PATCH v3 32/55] KVM: arm/arm64: vgic-new: Add GICv3 MMIO handling framework Christoffer Dall
2016-05-12 10:52 ` Andre Przywara
2016-05-12 10:58 ` Marc Zyngier
2016-05-06 10:45 ` [PATCH v3 33/55] KVM: arm/arm64: vgic-new: Add GICv3 CTLR, IIDR, TYPER handlers Andre Przywara
2016-05-12 11:47 ` Christoffer Dall
2016-05-12 12:33 ` Andre Przywara
2016-05-06 10:45 ` [PATCH v3 34/55] KVM: arm/arm64: vgic-new: Add GICv3 redistributor IIDR and TYPER handler Andre Przywara
2016-05-12 11:59 ` Christoffer Dall
2016-05-06 10:45 ` [PATCH v3 35/55] KVM: arm/arm64: vgic-new: Add GICv3 IDREGS register handler Andre Przywara
2016-05-12 12:12 ` Christoffer Dall
2016-05-12 12:37 ` Andre Przywara
2016-05-06 10:45 ` [PATCH v3 36/55] KVM: arm/arm64: vgic-new: Add GICv3 IROUTER register handlers Andre Przywara
2016-05-12 12:21 ` Christoffer Dall
2016-05-12 12:37 ` Marc Zyngier [this message]
2016-05-12 13:41 ` Christoffer Dall
2016-05-12 14:00 ` Andre Przywara
2016-05-12 14:20 ` Marc Zyngier
2016-05-06 10:45 ` [PATCH v3 37/55] KVM: arm/arm64: vgic-new: Add GICv3 SGI system register trap handler Andre Przywara
2016-05-12 12:40 ` Christoffer Dall
2016-05-06 10:45 ` [PATCH v3 38/55] KVM: arm/arm64: vgic-new: vgic_kvm_device: KVM device ops registration Andre Przywara
2016-05-13 10:11 ` Christoffer Dall
2016-05-06 10:45 ` [PATCH v3 39/55] KVM: arm/arm64: vgic-new: vgic_kvm_device: KVM_DEV_ARM_VGIC_GRP_NR_IRQS Andre Przywara
2016-05-13 10:11 ` Christoffer Dall
2016-05-06 10:45 ` [PATCH v3 40/55] KVM: arm/arm64: vgic-new: vgic_kvm_device: KVM_DEV_ARM_VGIC_GRP_CTRL Andre Przywara
2016-05-13 10:11 ` Christoffer Dall
2016-05-06 10:45 ` [PATCH v3 41/55] KVM: arm/arm64: vgic-new: vgic_kvm_device: implement kvm_vgic_addr Andre Przywara
2016-05-13 10:12 ` Christoffer Dall
2016-05-06 10:45 ` [PATCH v3 42/55] KVM: arm/arm64: vgic-new: vgic_kvm_device: KVM_DEV_ARM_VGIC_GRP_ADDR Andre Przywara
2016-05-13 10:12 ` Christoffer Dall
2016-05-06 10:45 ` [PATCH v3 43/55] KVM: arm/arm64: vgic-new: vgic_kvm_device: access to VGIC registers Andre Przywara
2016-05-12 18:30 ` Christoffer Dall
2016-05-13 12:24 ` Andre Przywara
2016-05-13 12:29 ` Christoffer Dall
2016-05-13 12:30 ` Marc Zyngier
2016-05-06 10:45 ` [PATCH v3 44/55] KVM: arm/arm64: vgic-new: Export register access interface Andre Przywara
2016-05-06 10:45 ` [PATCH v3 45/55] KVM: arm/arm64: vgic-new: Add userland access to VGIC dist registers Andre Przywara
2016-05-12 18:41 ` Christoffer Dall
2016-05-12 19:10 ` Andre Przywara
2016-05-13 7:51 ` Christoffer Dall
2016-05-06 10:45 ` [PATCH v3 46/55] KVM: arm/arm64: vgic-new: Add GICH_VMCR accessors Andre Przywara
2016-05-12 18:43 ` Christoffer Dall
2016-05-06 10:46 ` [PATCH v3 47/55] KVM: arm/arm64: vgic-new: Add userland GIC CPU interface access Andre Przywara
2016-05-09 17:27 ` Marc Zyngier
2016-05-11 8:24 ` Andre Przywara
2016-05-12 18:47 ` Christoffer Dall
2016-05-12 18:52 ` Andre Przywara
2016-05-13 7:53 ` Christoffer Dall
2016-05-13 10:44 ` Andre Przywara
2016-05-13 11:54 ` Christoffer Dall
2016-05-13 12:23 ` Andre Przywara
2016-05-13 12:32 ` Christoffer Dall
2016-05-06 10:46 ` [PATCH v3 48/55] KVM: arm/arm64: vgic-new: vgic_init: implement kvm_vgic_hyp_init Andre Przywara
2016-05-12 19:00 ` Christoffer Dall
2016-05-06 10:46 ` [PATCH v3 49/55] KVM: arm/arm64: vgic-new: vgic_init: implement vgic_create Andre Przywara
2016-05-12 19:08 ` Christoffer Dall
2016-05-06 10:46 ` [PATCH v3 50/55] KVM: arm/arm64: vgic-new: vgic_init: implement vgic_init Andre Przywara
2016-05-12 19:25 ` Christoffer Dall
2016-05-06 10:46 ` [PATCH v3 51/55] KVM: arm/arm64: vgic-new: vgic_init: implement map_resources Andre Przywara
2016-05-12 19:28 ` Christoffer Dall
2016-05-06 10:46 ` [PATCH v3 52/55] KVM: arm/arm64: vgic-new: Add vgic_v2/v3_enable Andre Przywara
2016-05-12 19:30 ` Christoffer Dall
2016-05-06 10:46 ` [PATCH v3 53/55] KVM: arm/arm64: vgic-new: Wire up irqfd injection Andre Przywara
2016-05-12 19:33 ` Christoffer Dall
2016-05-06 10:46 ` [PATCH v3 54/55] KVM: arm/arm64: vgic-new: implement mapped IRQ handling Andre Przywara
2016-05-12 19:36 ` Christoffer Dall
2016-05-06 10:46 ` [PATCH v3 55/55] KVM: arm/arm64: vgic-new: enable build Andre Przywara
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