From: Marc Zyngier <marc.zyngier@arm.com>
To: Christoffer Dall <cdall@linaro.org>
Cc: linux-kernel@vger.kernel.org,
linux-arm-kernel@lists.infradead.org,
kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org,
Christoffer Dall <christoffer.dall@linaro.org>,
Thomas Gleixner <tglx@linutronix.de>,
Jason Cooper <jason@lakedaemon.net>,
Eric Auger <eric.auger@redhat.com>,
Shanker Donthineni <shankerd@codeaurora.org>,
Mark Rutland <mark.rutland@arm.com>,
Shameerali Kolothum Thodi <shameerali.kolothum.thodi@huawei.com>
Subject: Re: [PATCH v3 56/59] KVM: arm/arm64: GICv4: Prevent heterogenous systems from using GICv4
Date: Wed, 30 Aug 2017 17:03:51 +0100 [thread overview]
Message-ID: <bcd17108-b035-a95f-67a4-4433e2be20ae@arm.com> (raw)
In-Reply-To: <20170828183550.GQ24649@cbox>
On 28/08/17 19:35, Christoffer Dall wrote:
> On Mon, Jul 31, 2017 at 06:26:34PM +0100, Marc Zyngier wrote:
>> The GICv4 architecture doesn't prevent CPUs implementing GICv4 to
>> cohabit with CPUs limited to GICv3 in the same system.
>>
>> This is mad (the sheduler would have to be made aware of the v4
>
> *scheduler
>
>> capability), and we're certainly not going to support this any
>> time soon. So let's check that all online CPUs are GICv4 capable,
>> and disable the functionnality if not.
>
> *functionality
>
>>
>> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
>> ---
>> include/linux/irqchip/arm-gic-v3.h | 2 ++
>> virt/kvm/arm/vgic/vgic-v3.c | 22 +++++++++++++++++++++-
>> 2 files changed, 23 insertions(+), 1 deletion(-)
>>
>> diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h
>> index 1ea576c8126f..dfa4a51643d6 100644
>> --- a/include/linux/irqchip/arm-gic-v3.h
>> +++ b/include/linux/irqchip/arm-gic-v3.h
>> @@ -532,6 +532,8 @@
>> #define ICH_VTR_SEIS_MASK (1 << ICH_VTR_SEIS_SHIFT)
>> #define ICH_VTR_A3V_SHIFT 21
>> #define ICH_VTR_A3V_MASK (1 << ICH_VTR_A3V_SHIFT)
>> +#define ICH_VTR_nV4_SHIFT 20
>> +#define ICH_VTR_nV4_MASK (1 << ICH_VTR_nV4_SHIFT)
>>
>> #define ICC_IAR1_EL1_SPURIOUS 0x3ff
>>
>> diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c
>> index 405733678c2f..252268e83ade 100644
>> --- a/virt/kvm/arm/vgic/vgic-v3.c
>> +++ b/virt/kvm/arm/vgic/vgic-v3.c
>> @@ -466,6 +466,18 @@ static int __init early_gicv4_enable(char *buf)
>> }
>> early_param("kvm-arm.vgic_v4_enable", early_gicv4_enable);
>>
>> +static void vgic_check_v4_cpuif(void *param)
>> +{
>> + u32 ich_vtr_el2 = kvm_call_hyp(__vgic_v3_get_ich_vtr_el2);
>> + bool *v4 = param, this_cpu_is_v4;
>> +
>> + this_cpu_is_v4 = !(ich_vtr_el2 & ICH_VTR_nV4_MASK);
>> + if (!this_cpu_is_v4)
>> + kvm_info("CPU%d is not GICv4 capable\n", smp_processor_id());
>> +
>> + *v4 &= this_cpu_is_v4;
>
> nit: You could make this function look slightly less scary by declaring
> this_cpu_is_v4 on a separate line and not use a bitwise operator on a
> boolean type. Actually, having a function called 'check' with a side
> effect is not the nicest thing either, so why not just return what this
> particular CPU does and do the comparison in the calling loop.
Fair enough.
> #bikeshedding
How about this on top:
diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c
index 01eaf4ee2f63..e471750dc0a1 100644
--- a/virt/kvm/arm/vgic/vgic-v3.c
+++ b/virt/kvm/arm/vgic/vgic-v3.c
@@ -469,18 +469,16 @@ early_param("kvm-arm.vgic_v4_enable", early_gicv4_enable);
static void vgic_check_v4_cpuif(void *param)
{
u32 ich_vtr_el2 = kvm_call_hyp(__vgic_v3_get_ich_vtr_el2);
- bool *v4 = param, this_cpu_is_v4;
+ bool *v4 = param;
- this_cpu_is_v4 = !(ich_vtr_el2 & ICH_VTR_nV4_MASK);
- if (!this_cpu_is_v4)
+ *v4 = !(ich_vtr_el2 & ICH_VTR_nV4_MASK);
+ if (!*v4)
kvm_info("CPU%d is not GICv4 capable\n", smp_processor_id());
-
- *v4 &= this_cpu_is_v4;
}
/**
* vgic_v3_probe - probe for a GICv3 compatible interrupt controller in DT
- * @node: pointer to the DT node
+ * @info: pointer to the firmware-agnostic GIC information
*
* Returns 0 if a GICv3 has been found, returns an error code otherwise
*/
@@ -504,9 +502,14 @@ int vgic_v3_probe(const struct gic_kvm_info *info)
if (info->has_v4) {
int cpu;
- for_each_online_cpu(cpu)
+ for_each_online_cpu(cpu) {
+ bool enable;
+
smp_call_function_single(cpu, vgic_check_v4_cpuif,
- &gicv4_enable, 1);
+ &enable, 1);
+ gicv4_enable = gicv4_enable && enable;
+ }
+
kvm_vgic_global_state.has_gicv4 = gicv4_enable;
kvm_info("GICv4 support %sabled\n",
gicv4_enable ? "en" : "dis");
Thanks,
M.
--
Jazz is not dead. It just smells funny...
next prev parent reply other threads:[~2017-08-30 16:03 UTC|newest]
Thread overview: 118+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-07-31 17:25 [PATCH v3 00/59] irqchip: KVM: Add support for GICv4 Marc Zyngier
2017-07-31 17:25 ` [PATCH v3 01/59] genirq: Let irq_set_vcpu_affinity() iterate over hierarchy Marc Zyngier
2017-07-31 17:25 ` [PATCH v3 02/59] irqchip/gic-v3: Add redistributor iterator Marc Zyngier
2017-07-31 17:25 ` [PATCH v3 03/59] irqchip/gic-v3: Add VLPI/DirectLPI discovery Marc Zyngier
2017-07-31 17:25 ` [PATCH v3 04/59] irqchip/gic-v3-its: Move LPI definitions around Marc Zyngier
2017-07-31 17:25 ` [PATCH v3 05/59] irqchip/gic-v3-its: Add probing for VLPI properties Marc Zyngier
2017-07-31 17:25 ` [PATCH v3 06/59] irqchip/gic-v3-its: Macro-ize its_send_single_command Marc Zyngier
2017-07-31 17:25 ` [PATCH v3 07/59] irqchip/gic-v3-its: Implement irq_set_irqchip_state for pending state Marc Zyngier
2017-07-31 17:25 ` [PATCH v3 08/59] irqchip/gic-v3-its: Split out property table allocation Marc Zyngier
2017-07-31 17:25 ` [PATCH v3 09/59] irqchip/gic-v3-its: Allow use of indirect VCPU tables Marc Zyngier
2017-07-31 17:25 ` [PATCH v3 10/59] irqchip/gic-v3-its: Split out pending table allocation Marc Zyngier
2017-07-31 17:25 ` [PATCH v3 11/59] irqchip/gic-v3-its: Rework LPI freeing Marc Zyngier
2017-07-31 17:25 ` [PATCH v3 12/59] irqchip/gic-v3-its: Generalize device table allocation Marc Zyngier
2017-07-31 17:25 ` [PATCH v3 13/59] irqchip/gic-v3-its: Generalize LPI configuration Marc Zyngier
2017-07-31 17:25 ` [PATCH v3 14/59] irqchip/gic-v4: Add management structure definitions Marc Zyngier
2017-07-31 17:25 ` [PATCH v3 15/59] irqchip/gic-v3-its: Add GICv4 ITS command definitions Marc Zyngier
2017-07-31 17:25 ` [PATCH v3 16/59] irqchip/gic-v3-its: Add VLPI configuration hook Marc Zyngier
2017-07-31 17:25 ` [PATCH v3 17/59] irqchip/gic-v3-its: Add VLPI map/unmap operations Marc Zyngier
2017-07-31 17:25 ` [PATCH v3 18/59] irqchip/gic-v3-its: Add VLPI configuration handling Marc Zyngier
2017-07-31 17:25 ` [PATCH v3 19/59] irqchip/gic-v3-its: Add VPE domain infrastructure Marc Zyngier
2017-07-31 17:25 ` [PATCH v3 20/59] irqchip/gic-v3-its: Add VPE irq domain allocation/teardown Marc Zyngier
2017-07-31 17:25 ` [PATCH v3 21/59] irqchip/gic-v3-its: Add VPE irq domain [de]activation Marc Zyngier
2017-07-31 17:26 ` [PATCH v3 22/59] irqchip/gic-v3-its: Add VPENDBASER/VPROPBASER accessors Marc Zyngier
2017-07-31 17:26 ` [PATCH v3 23/59] irqchip/gic-v3-its: Add VPE scheduling Marc Zyngier
2017-07-31 17:26 ` [PATCH v3 24/59] irqchip/gic-v3-its: Add VPE invalidation hook Marc Zyngier
2017-07-31 17:26 ` [PATCH v3 25/59] irqchip/gic-v3-its: Add VPE affinity changes Marc Zyngier
2017-07-31 17:26 ` [PATCH v3 26/59] irqchip/gic-v3-its: Add VPE interrupt masking Marc Zyngier
2017-07-31 17:26 ` [PATCH v3 27/59] irqchip/gic-v3-its: Support VPE doorbell invalidation even when !DirectLPI Marc Zyngier
2017-07-31 17:26 ` [PATCH v3 28/59] irqchip/gic-v3-its: Allow doorbell interrupts to be injected/cleared Marc Zyngier
2017-07-31 17:26 ` [PATCH v3 29/59] irqchip/gic-v3-its: Set implementation defined bit to enable VLPIs Marc Zyngier
2017-07-31 17:26 ` [PATCH v3 30/59] irqchip/gic-v4: Add per-VM VPE domain creation Marc Zyngier
2017-07-31 17:26 ` [PATCH v3 31/59] irqchip/gic-v4: Add VPE command interface Marc Zyngier
2017-07-31 17:26 ` [PATCH v3 32/59] irqchip/gic-v4: Add VLPI configuration interface Marc Zyngier
2017-07-31 17:26 ` [PATCH v3 33/59] irqchip/gic-v4: Add some basic documentation Marc Zyngier
2017-07-31 17:26 ` [PATCH v3 34/59] irqchip/gic-v4: Enable low-level GICv4 operations Marc Zyngier
2017-07-31 17:26 ` [PATCH v3 35/59] irqchip/gic-v3: Advertise GICv4 support to KVM Marc Zyngier
2017-07-31 17:26 ` [PATCH v3 36/59] KVM: arm: Select ARM_GIC_V3 and ARM_GIC_V3_ITS Marc Zyngier
2017-08-26 19:49 ` Christoffer Dall
2017-07-31 17:26 ` [PATCH v3 37/59] KVM: arm/arm64: vgic: Move kvm_vgic_destroy call around Marc Zyngier
2017-08-26 19:49 ` Christoffer Dall
2017-07-31 17:26 ` [PATCH v3 38/59] KVM: arm/arm64: vITS: Add MSI translation helpers Marc Zyngier
2017-08-26 19:49 ` Christoffer Dall
2017-07-31 17:26 ` [PATCH v3 39/59] KVM: arm/arm64: GICv4: Add property field and per-VM predicate Marc Zyngier
2017-08-26 19:49 ` Christoffer Dall
2017-08-30 9:46 ` Marc Zyngier
2017-07-31 17:26 ` [PATCH v3 40/59] KVM: arm/arm64: GICv4: Add init/teardown of the per-VM vPE irq domain Marc Zyngier
2017-08-26 19:49 ` Christoffer Dall
2017-08-30 9:50 ` Marc Zyngier
2017-07-31 17:26 ` [PATCH v3 41/59] KVM: arm/arm64: GICv4: Wire mapping/unmapping of VLPIs in VFIO irq bypass Marc Zyngier
2017-08-26 19:48 ` Christoffer Dall
2017-08-30 9:42 ` Marc Zyngier
2017-08-30 10:20 ` Auger Eric
2017-08-30 10:42 ` Marc Zyngier
2017-08-30 12:54 ` Auger Eric
2017-08-30 10:28 ` Marc Zyngier
2017-08-30 11:46 ` Christoffer Dall
2017-08-30 12:53 ` Marc Zyngier
2017-08-30 19:59 ` Christoffer Dall
2017-08-31 10:24 ` Marc Zyngier
2017-08-31 12:36 ` Christoffer Dall
2017-07-31 17:26 ` [PATCH v3 42/59] KVM: arm/arm64: GICv4: Handle INT command applied to a VLPI Marc Zyngier
2017-08-28 18:18 ` Christoffer Dall
2017-07-31 17:26 ` [PATCH v3 43/59] KVM: arm/arm64: GICv4: Unmap VLPI when freeing an LPI Marc Zyngier
2017-08-28 18:18 ` Christoffer Dall
2017-08-30 11:03 ` Marc Zyngier
2017-07-31 17:26 ` [PATCH v3 44/59] KVM: arm/arm64: GICv4: Handle MOVI applied to a VLPI Marc Zyngier
2017-08-28 18:18 ` Christoffer Dall
2017-08-30 14:08 ` Marc Zyngier
2017-08-30 20:04 ` Christoffer Dall
2017-07-31 17:26 ` [PATCH v3 45/59] KVM: arm/arm64: GICv4: Handle CLEAR " Marc Zyngier
2017-08-28 18:18 ` Christoffer Dall
2017-07-31 17:26 ` [PATCH v3 46/59] KVM: arm/arm64: GICv4: Handle MOVALL applied to a vPE Marc Zyngier
2017-08-28 18:18 ` Christoffer Dall
2017-08-30 14:46 ` Marc Zyngier
2017-08-30 20:10 ` Christoffer Dall
2017-07-31 17:26 ` [PATCH v3 47/59] KVM: arm/arm64: GICv4: Propagate property updates to VLPIs Marc Zyngier
2017-08-28 18:18 ` Christoffer Dall
2017-07-31 17:26 ` [PATCH v3 48/59] KVM: arm/arm64: GICv4: Handle INVALL applied to a vPE Marc Zyngier
2017-08-28 18:18 ` Christoffer Dall
2017-07-31 17:26 ` [PATCH v3 49/59] KVM: arm/arm64: GICv4: Propagate VLPI properties at map time Marc Zyngier
2017-08-28 18:18 ` Christoffer Dall
2017-08-30 14:56 ` Marc Zyngier
2017-08-30 20:12 ` Christoffer Dall
2017-07-31 17:26 ` [PATCH v3 50/59] KVM: arm/arm64: GICv4: Use pending_last as a scheduling hint Marc Zyngier
2017-08-28 18:18 ` Christoffer Dall
2017-07-31 17:26 ` [PATCH v3 51/59] KVM: arm/arm64: GICv4: Add doorbell interrupt handling Marc Zyngier
2017-08-04 7:44 ` Marc Zyngier
2017-08-28 18:18 ` Christoffer Dall
2017-08-30 10:31 ` Andrew Jones
2017-08-30 11:55 ` Christoffer Dall
2017-08-30 12:28 ` Andrew Jones
2017-08-31 12:18 ` Marc Zyngier
2017-08-31 12:41 ` Christoffer Dall
2017-08-28 18:18 ` Christoffer Dall
2017-08-30 15:36 ` Marc Zyngier
2017-08-30 20:58 ` Christoffer Dall
2017-08-31 8:19 ` Marc Zyngier
2017-09-06 9:06 ` Shannon Zhao
2017-07-31 17:26 ` [PATCH v3 52/59] KVM: arm/arm64: GICv4: Use the doorbell interrupt as an unblocking source Marc Zyngier
2017-08-28 18:19 ` Christoffer Dall
2017-07-31 17:26 ` [PATCH v3 53/59] KVM: arm/arm64: GICv4: Hook vPE scheduling into vgic flush/sync Marc Zyngier
2017-08-28 18:17 ` Christoffer Dall
2017-08-30 9:59 ` Marc Zyngier
2017-08-30 11:56 ` Christoffer Dall
2017-07-31 17:26 ` [PATCH v3 54/59] KVM: arm/arm64: GICv4: Enable virtual cpuif if VLPIs can be delivered Marc Zyngier
2017-08-28 18:20 ` Christoffer Dall
2017-07-31 17:26 ` [PATCH v3 55/59] KVM: arm/arm64: GICv4: Enable VLPI support Marc Zyngier
2017-08-28 18:25 ` Christoffer Dall
2017-07-31 17:26 ` [PATCH v3 56/59] KVM: arm/arm64: GICv4: Prevent heterogenous systems from using GICv4 Marc Zyngier
2017-08-28 18:35 ` Christoffer Dall
2017-08-30 16:03 ` Marc Zyngier [this message]
2017-08-30 21:00 ` Christoffer Dall
2017-07-31 17:26 ` [PATCH v3 57/59] KVM: arm/arm64: GICv4: Theory of operations Marc Zyngier
2017-08-28 18:18 ` Christoffer Dall
2017-08-30 11:30 ` Marc Zyngier
2017-08-30 11:58 ` Christoffer Dall
2017-07-31 17:26 ` [PATCH v3 58/59] irqchip/gic-v3-its: Pass its_node pointer to each command bulder Marc Zyngier
2017-07-31 17:26 ` [PATCH v3 59/59] irqchip/gic-v3-its: Workaround Huawei D05 redistributor addressing Marc Zyngier
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