From: Auger Eric <eric.auger@redhat.com>
To: Marc Zyngier <marc.zyngier@arm.com>,
linux-arm-kernel@lists.infradead.org,
kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org,
linux-kernel@vger.kernel.org
Cc: Mark Rutland <mark.rutland@arm.com>,
Andre Przywara <Andre.Przywara@arm.com>,
Shameerali Kolothum Thodi <shameerali.kolothum.thodi@huawei.com>,
Christoffer Dall <christoffer.dall@linaro.org>,
Shanker Donthineni <shankerd@codeaurora.org>
Subject: Re: [PATCH v5 24/26] KVM: arm/arm64: GICv4: Prevent userspace from changing doorbell affinity
Date: Tue, 7 Nov 2017 23:17:51 +0100 [thread overview]
Message-ID: <27d2f799-c2de-27a9-8e92-21bbdd583307@redhat.com> (raw)
In-Reply-To: <20171027142855.21584-25-marc.zyngier@arm.com>
Hi,
On 27/10/2017 16:28, Marc Zyngier wrote:
> We so far allocate the doorbell interrupts without taking any
> special measure regarding the affinity of these interrupts. We
> simply move them around as required when the vcpu gets scheduled
> on a different CPU.
>
> But that's counting without userspace (and the evil irqbalance) that
> can try and move the VPE interrupt around, causing the ITS code
> to emit VMOVP commands and remap the doorbell to another redistributor.
> Worse, this can happen while the vcpu is running, causing all kind
> of trouble if the VPE is already resident, and we end-up in UNPRED
> territory.
>
> So let's take a definitive action and prevent userspace from messing
> with us. This is just a matter of adding IRQ_NO_BALANCING to the
> set of flags we already have, letting the kernel in sole control
> of the affinity.
>
> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Eric
> ---
> virt/kvm/arm/vgic/vgic-v4.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/virt/kvm/arm/vgic/vgic-v4.c b/virt/kvm/arm/vgic/vgic-v4.c
> index d7fe610bb1f5..d10e18eabd3b 100644
> --- a/virt/kvm/arm/vgic/vgic-v4.c
> +++ b/virt/kvm/arm/vgic/vgic-v4.c
> @@ -23,6 +23,8 @@
>
> #include "vgic.h"
>
> +#define DB_IRQ_FLAGS (IRQ_NOAUTOEN | IRQ_DISABLE_UNLAZY | IRQ_NO_BALANCING)
> +
> static irqreturn_t vgic_v4_doorbell_handler(int irq, void *info)
> {
> struct kvm_vcpu *vcpu = info;
> @@ -83,7 +85,7 @@ int vgic_v4_init(struct kvm *kvm)
> * doorbell could kick us out of the guest too
> * early...
> */
> - irq_set_status_flags(irq, IRQ_NOAUTOEN | IRQ_DISABLE_UNLAZY);
> + irq_set_status_flags(irq, DB_IRQ_FLAGS);
> ret = request_irq(irq, vgic_v4_doorbell_handler,
> 0, "vcpu", vcpu);
> if (ret) {
> @@ -121,7 +123,7 @@ void vgic_v4_teardown(struct kvm *kvm)
> struct kvm_vcpu *vcpu = kvm_get_vcpu(kvm, i);
> int irq = its_vm->vpes[i]->irq;
>
> - irq_clear_status_flags(irq, IRQ_NOAUTOEN | IRQ_DISABLE_UNLAZY);
> + irq_clear_status_flags(irq, DB_IRQ_FLAGS);
> free_irq(irq, vcpu);
> }
>
>
next prev parent reply other threads:[~2017-11-07 22:17 UTC|newest]
Thread overview: 78+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-10-27 14:28 [PATCH v5 00/26] KVM/ARM: Add support for GICv4 Marc Zyngier
2017-10-27 14:28 ` [PATCH v5 01/26] irqchip/gic-v3-its: Setup VLPI properties at map time Marc Zyngier
2017-10-30 6:46 ` Christoffer Dall
2017-10-27 14:28 ` [PATCH v5 02/26] KVM: arm/arm64: register irq bypass consumer on ARM/ARM64 Marc Zyngier
2017-10-30 6:47 ` Christoffer Dall
2017-10-27 14:28 ` [PATCH v5 03/26] KVM: arm/arm64: vgic: restructure kvm_vgic_(un)map_phys_irq Marc Zyngier
2017-10-27 14:28 ` [PATCH v5 04/26] KVM: arm: Select ARM_GIC_V3 and ARM_GIC_V3_ITS Marc Zyngier
2017-10-27 14:28 ` [PATCH v5 05/26] KVM: arm/arm64: vgic: Move kvm_vgic_destroy call around Marc Zyngier
2017-10-27 14:28 ` [PATCH v5 06/26] KVM: arm/arm64: vITS: Add MSI translation helpers Marc Zyngier
2017-11-07 20:34 ` Auger Eric
2017-10-27 14:28 ` [PATCH v5 07/26] KVM: arm/arm64: vITS: Add a helper to update the affinity of an LPI Marc Zyngier
2017-11-07 13:44 ` Auger Eric
2017-10-27 14:28 ` [PATCH v5 08/26] KVM: arm/arm64: GICv4: Add property field and per-VM predicate Marc Zyngier
2017-11-07 20:30 ` Auger Eric
2017-10-27 14:28 ` [PATCH v5 09/26] KVM: arm/arm64: GICv4: Add init/teardown of the per-VM vPE irq domain Marc Zyngier
2017-11-07 13:08 ` Auger Eric
2017-11-10 8:20 ` Christoffer Dall
2017-11-10 8:55 ` Marc Zyngier
2017-11-07 13:09 ` Auger Eric
2017-10-27 14:28 ` [PATCH v5 10/26] KVM: arm/arm64: GICv4: Wire mapping/unmapping of VLPIs in VFIO irq bypass Marc Zyngier
2017-11-07 13:06 ` Auger Eric
2017-11-07 14:42 ` Marc Zyngier
2017-11-07 15:59 ` Auger Eric
2017-11-08 11:30 ` Marc Zyngier
2017-11-10 8:28 ` Christoffer Dall
2017-11-10 9:05 ` Marc Zyngier
2017-11-10 9:41 ` Christoffer Dall
2017-10-27 14:28 ` [PATCH v5 11/26] KVM: arm/arm64: GICv4: Handle INT command applied to a VLPI Marc Zyngier
2017-11-07 20:15 ` Auger Eric
2017-11-08 11:40 ` Marc Zyngier
2017-11-08 14:14 ` Auger Eric
2017-10-27 14:28 ` [PATCH v5 12/26] KVM: arm/arm64: GICv4: Unmap VLPI when freeing an LPI Marc Zyngier
2017-11-07 20:28 ` Auger Eric
2017-11-08 11:52 ` Marc Zyngier
2017-11-08 14:14 ` Auger Eric
2017-10-27 14:28 ` [PATCH v5 13/26] KVM: arm/arm64: GICv4: Propagate affinity changes to the physical ITS Marc Zyngier
2017-11-07 21:01 ` Auger Eric
2017-11-08 12:05 ` Marc Zyngier
2017-10-27 14:28 ` [PATCH v5 14/26] KVM: arm/arm64: GICv4: Handle CLEAR applied to a VLPI Marc Zyngier
2017-11-07 21:04 ` Auger Eric
2017-10-27 14:28 ` [PATCH v5 15/26] KVM: arm/arm64: GICv4: Handle MOVALL applied to a vPE Marc Zyngier
2017-11-07 21:06 ` Auger Eric
2017-10-27 14:28 ` [PATCH v5 16/26] KVM: arm/arm64: GICv4: Propagate property updates to VLPIs Marc Zyngier
2017-11-07 21:28 ` Auger Eric
2017-11-08 15:08 ` Marc Zyngier
2017-11-10 8:37 ` Christoffer Dall
2017-11-10 8:58 ` Marc Zyngier
2017-10-27 14:28 ` [PATCH v5 17/26] KVM: arm/arm64: GICv4: Handle INVALL applied to a vPE Marc Zyngier
2017-11-07 21:23 ` Auger Eric
2017-11-10 8:41 ` Christoffer Dall
2017-11-10 8:56 ` Marc Zyngier
2017-10-27 14:28 ` [PATCH v5 18/26] KVM: arm/arm64: GICv4: Use pending_last as a scheduling hint Marc Zyngier
2017-11-07 21:38 ` Auger Eric
2017-10-27 14:28 ` [PATCH v5 19/26] KVM: arm/arm64: GICv4: Add doorbell interrupt handling Marc Zyngier
2017-11-07 21:43 ` Auger Eric
2017-10-27 14:28 ` [PATCH v5 20/26] KVM: arm/arm64: GICv4: Use the doorbell interrupt as an unblocking source Marc Zyngier
2017-11-07 21:45 ` Auger Eric
2017-10-27 14:28 ` [PATCH v5 21/26] KVM: arm/arm64: GICv4: Hook vPE scheduling into vgic flush/sync Marc Zyngier
2017-11-07 21:54 ` Auger Eric
2017-11-07 22:14 ` Auger Eric
2017-10-27 14:28 ` [PATCH v5 22/26] KVM: arm/arm64: GICv4: Enable virtual cpuif if VLPIs can be delivered Marc Zyngier
2017-11-08 8:46 ` Auger Eric
2017-10-27 14:28 ` [PATCH v5 23/26] KVM: arm/arm64: GICv4: Prevent a VM using GICv4 from being saved Marc Zyngier
2017-11-07 15:24 ` Auger Eric
2017-11-07 15:38 ` Marc Zyngier
2017-11-07 16:12 ` Auger Eric
2017-11-07 16:34 ` Marc Zyngier
2017-11-07 22:24 ` Auger Eric
2017-11-08 9:35 ` Auger Eric
2017-10-27 14:28 ` [PATCH v5 24/26] KVM: arm/arm64: GICv4: Prevent userspace from changing doorbell affinity Marc Zyngier
2017-10-30 6:51 ` Christoffer Dall
2017-11-07 22:17 ` Auger Eric [this message]
2017-10-27 14:28 ` [PATCH v5 25/26] KVM: arm/arm64: GICv4: Enable VLPI support Marc Zyngier
2017-11-08 8:44 ` Auger Eric
2017-11-08 15:14 ` Marc Zyngier
2017-10-27 14:28 ` [PATCH v5 26/26] KVM: arm/arm64: GICv4: Theory of operations Marc Zyngier
2017-11-08 9:13 ` Auger Eric
2017-11-08 15:19 ` Marc Zyngier
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=27d2f799-c2de-27a9-8e92-21bbdd583307@redhat.com \
--to=eric.auger@redhat.com \
--cc=Andre.Przywara@arm.com \
--cc=christoffer.dall@linaro.org \
--cc=kvm@vger.kernel.org \
--cc=kvmarm@lists.cs.columbia.edu \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=marc.zyngier@arm.com \
--cc=mark.rutland@arm.com \
--cc=shameerali.kolothum.thodi@huawei.com \
--cc=shankerd@codeaurora.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).