[PATCH 0/3] KVM: arm64: Fix userspace access to HW pending state

From: Marc Zyngier <maz@kernel.org>
To: kvmarm@lists.cs.columbia.edu,
	linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org
Cc: Eric Auger <eauger@redhat.com>,
	Ricardo Koller <ricarkol@google.com>,
	James Morse <james.morse@arm.com>,
	Suzuki K Poulose <suzuki.poulose@arm.com>,
	Alexandru Elisei <alexandru.elisei@arm.com>,
	Oliver Upton <oupton@google.com>,
	kernel-team@android.com
Subject: [PATCH 0/3] KVM: arm64: Fix userspace access to HW pending state
Date: Thu,  2 Jun 2022 09:30:22 +0100	[thread overview]
Message-ID: <20220602083025.1110433-1-maz@kernel.org> (raw)

Eric reported that a Seattle system was pretty unhappy about VM
migration, and the trace pointed to a glaring bug in the way the GICv2
emulation code reported the interrupt pending state to userspace for
HW interrupts, specially if the interrupt state is per-CPU, as this is
the case for the timer...

Fixing this actually results in a minor cleanup, followed by a bit of
extra hardening so that we can catch further issues in this area
without completely taking the system down.

Unless someone screams, I plan to take these in as fixes as quickly as
possible, with the first patch being an obvious stable candidate. I'd
appreciate it if people could verify that VM migration still works
correctly for both GICv2 and GICv3.

Thanks,

	M.

Marc Zyngier (3):
  KVM: arm64: Don't read a HW interrupt pending state in user context
  KVM: arm64: Replace vgic_v3_uaccess_read_pending with
    vgic_uaccess_read_pending
  KVM: arm64: Warn if accessing timer pending state outside of vcpu
    context

 arch/arm64/kvm/arch_timer.c        |  3 +++
 arch/arm64/kvm/vgic/vgic-mmio-v2.c |  4 +--
 arch/arm64/kvm/vgic/vgic-mmio-v3.c | 40 ++----------------------------
 arch/arm64/kvm/vgic/vgic-mmio.c    | 19 +++++++++++---
 arch/arm64/kvm/vgic/vgic-mmio.h    |  3 +++
 5 files changed, 26 insertions(+), 43 deletions(-)

-- 
2.34.1