| Message ID | 1432125020-6570-1-git-send-email-luis.henriques@canonical.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c index 98160610fe56..b224b729cd0f 100644 --- a/virt/kvm/arm/vgic.c +++ b/virt/kvm/arm/vgic.c @@ -1387,7 +1387,8 @@ out: int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int irq_num, bool level) { - if (vgic_update_irq_state(kvm, cpuid, irq_num, level)) + if (likely(vgic_initialized(kvm)) && + vgic_update_irq_state(kvm, cpuid, irq_num, level)) vgic_kick_vcpus(kvm); return 0;
This is a note to let you know that I have just added a patch titled KVM: ARM: vgic: plug irq injection race to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.16.y-queue This patch is scheduled to be released in version 3.16.7-ckt12. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.16.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From e719b4c8f478d6840f62063658d703f22a1a97cf Mon Sep 17 00:00:00 2001 From: Marc Zyngier <marc.zyngier@arm.com> Date: Tue, 8 Jul 2014 12:09:00 +0100 Subject: KVM: ARM: vgic: plug irq injection race commit 71afaba4a2e98bb7bdeba5078370ab43d46e67a1 upstream. As it stands, nothing prevents userspace from injecting an interrupt before the guest's GIC is actually initialized. This goes unnoticed so far (as everything is pretty much statically allocated), but ends up exploding in a spectacular way once we switch to a more dynamic allocation (the GIC data structure isn't there yet). The fix is to test for the "ready" flag in the VGIC distributor before trying to inject the interrupt. Note that in order to avoid breaking userspace, we have to ignore what is essentially an error. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org> [ luis: backported to 3.16: used shannon's backport to 3.14 ] Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- virt/kvm/arm/vgic.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)