]> git.baikalelectronics.ru Git - kernel.git/commit
arm/arm64: KVM: Keep elrsr/aisr in sync with software model
authorChristoffer Dall <christoffer.dall@linaro.org>
Fri, 13 Mar 2015 17:02:56 +0000 (17:02 +0000)
committerChristoffer Dall <christoffer.dall@linaro.org>
Sat, 14 Mar 2015 12:42:07 +0000 (13:42 +0100)
commitfaaa788c3f9f7c4f445fefb0cf72262d44ce663d
treefbcd8af3ba6bf67bf693bca8933cb98d23e07d11
parent5d3a8797b7ce88e1185d14551cfb6ff91a7e8b72
arm/arm64: KVM: Keep elrsr/aisr in sync with software model

There is an interesting bug in the vgic code, which manifests itself
when the KVM run loop has a signal pending or needs a vmid generation
rollover after having disabled interrupts but before actually switching
to the guest.

In this case, we flush the vgic as usual, but we sync back the vgic
state and exit to userspace before entering the guest.  The consequence
is that we will be syncing the list registers back to the software model
using the GICH_ELRSR and GICH_EISR from the last execution of the guest,
potentially overwriting a list register containing an interrupt.

This showed up during migration testing where we would capture a state
where the VM has masked the arch timer but there were no interrupts,
resulting in a hung test.

Cc: Marc Zyngier <marc.zyngier@arm.com>
Reported-by: Alex Bennee <alex.bennee@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
include/kvm/arm_vgic.h
virt/kvm/arm/vgic-v2.c
virt/kvm/arm/vgic-v3.c
virt/kvm/arm/vgic.c