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From: Marc Zyngier <maz@kernel.org>
To: "Paolo Bonzini" <pbonzini@redhat.com>,
	"Radim Krčmář" <rkrcmar@redhat.com>,
	"Julien Thierry" <julien.thierry.kdev@gmail.com>,
	"Suzuki K Poulose" <suzuki.poulose@arm.com>,
	"James Morse" <james.morse@arm.com>,
	"Joerg Roedel" <joro@8bytes.org>,
	"Suravee Suthikulpanit" <Suravee.Suthikulpanit@amd.com>,
	Tangnianyao <tangnianyao@huawei.com>
Cc: kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org
Subject: [PATCH 0/2] KVM: arm/arm64: Fix guest's PMR synchronization when blocking on WFI
Date: Fri,  2 Aug 2019 11:37:07 +0100	[thread overview]
Message-ID: <20190802103709.70148-1-maz@kernel.org> (raw)

It recently came to light that if we run a guest that actively uses
interrupt priorities to block interrupts, vcpus can end-up being
blocked while they shouldn't, leading to an unresponsive guest (a
slightly less than desirable outcome).

Patch #1 fixes the issue (which has been with us since 4.12), which I plan
to take in for 5.3 with immediate backport to stable.

Patch #2 is more of an RFC, as it also impacts the SVN AVIC support. It
moves the kvm_arch_vcpu_blocking callback to happen earlier, leading to
much better performances on ARM, and leading to the above fix to be
applied at the best possible spot. I'd welcome any comment/testing on
this, specially on non-ARM systems.

Marc Zyngier (2):
  KVM: arm/arm64: Sync ICH_VMCR_EL2 back when about to block
  KVM: Call kvm_arch_vcpu_blocking early into the blocking sequence

 include/kvm/arm_vgic.h      |  1 +
 virt/kvm/arm/arm.c          | 11 +++++++++++
 virt/kvm/arm/vgic/vgic-v2.c |  9 ++++++++-
 virt/kvm/arm/vgic/vgic-v3.c |  7 ++++++-
 virt/kvm/arm/vgic/vgic.c    | 11 +++++++++++
 virt/kvm/arm/vgic/vgic.h    |  2 ++
 virt/kvm/kvm_main.c         |  7 +++----
 7 files changed, 42 insertions(+), 6 deletions(-)

-- 
2.20.1

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WARNING: multiple messages have this Message-ID (diff)
From: Marc Zyngier <maz@kernel.org>
To: "Paolo Bonzini" <pbonzini@redhat.com>,
	"Radim Krčmář" <rkrcmar@redhat.com>,
	"Julien Thierry" <julien.thierry.kdev@gmail.com>,
	"Suzuki K Poulose" <suzuki.poulose@arm.com>,
	"James Morse" <james.morse@arm.com>,
	"Joerg Roedel" <joro@8bytes.org>,
	"Suravee Suthikulpanit" <Suravee.Suthikulpanit@amd.com>,
	Tangnianyao <tangnianyao@huawei.com>
Cc: kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu
Subject: [PATCH 0/2] KVM: arm/arm64: Fix guest's PMR synchronization when blocking on WFI
Date: Fri,  2 Aug 2019 11:37:07 +0100	[thread overview]
Message-ID: <20190802103709.70148-1-maz@kernel.org> (raw)

It recently came to light that if we run a guest that actively uses
interrupt priorities to block interrupts, vcpus can end-up being
blocked while they shouldn't, leading to an unresponsive guest (a
slightly less than desirable outcome).

Patch #1 fixes the issue (which has been with us since 4.12), which I plan
to take in for 5.3 with immediate backport to stable.

Patch #2 is more of an RFC, as it also impacts the SVN AVIC support. It
moves the kvm_arch_vcpu_blocking callback to happen earlier, leading to
much better performances on ARM, and leading to the above fix to be
applied at the best possible spot. I'd welcome any comment/testing on
this, specially on non-ARM systems.

Marc Zyngier (2):
  KVM: arm/arm64: Sync ICH_VMCR_EL2 back when about to block
  KVM: Call kvm_arch_vcpu_blocking early into the blocking sequence

 include/kvm/arm_vgic.h      |  1 +
 virt/kvm/arm/arm.c          | 11 +++++++++++
 virt/kvm/arm/vgic/vgic-v2.c |  9 ++++++++-
 virt/kvm/arm/vgic/vgic-v3.c |  7 ++++++-
 virt/kvm/arm/vgic/vgic.c    | 11 +++++++++++
 virt/kvm/arm/vgic/vgic.h    |  2 ++
 virt/kvm/kvm_main.c         |  7 +++----
 7 files changed, 42 insertions(+), 6 deletions(-)

-- 
2.20.1


             reply	other threads:[~2019-08-02 10:37 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-08-02 10:37 Marc Zyngier [this message]
2019-08-02 10:37 ` [PATCH 0/2] KVM: arm/arm64: Fix guest's PMR synchronization when blocking on WFI Marc Zyngier
2019-08-02 10:37 ` [PATCH 1/2] KVM: arm/arm64: Sync ICH_VMCR_EL2 back when about to block Marc Zyngier
2019-08-02 10:37   ` Marc Zyngier
2019-08-02 10:37 ` [PATCH 2/2] KVM: Call kvm_arch_vcpu_blocking early into the blocking sequence Marc Zyngier
2019-08-02 10:37   ` Marc Zyngier
2019-08-02 10:46   ` Paolo Bonzini
2019-08-02 10:46     ` Paolo Bonzini
2019-08-18 17:53     ` Marc Zyngier
2019-08-18 17:53       ` Marc Zyngier

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