linux-toradex.git/virt/kvm/ioapic.c, branch v3.16-rc1

KVM: ioapic: try to recover if pending_eoi goes out of range

2014-04-04T15:17:24+00:00

The RTC tracking code tracks the cardinality of rtc_status.dest_map
into rtc_status.pending_eoi.  It has some WARN_ONs that trigger if
pending_eoi ever becomes negative; however, these do not do anything
to recover, and it bad things will happen soon after they trigger.

When the next RTC interrupt is triggered, rtc_check_coalesced() will
return false, but ioapic_service will find pending_eoi != 0 and
do a BUG_ON.  To avoid this, should pending_eoi ever be nonzero,
call kvm_rtc_eoi_tracking_restore_all to recompute a correct
dest_map and pending_eoi.

Signed-off-by: Paolo Bonzini

KVM: ioapic: fix assignment of ioapic->rtc_status.pending_eoi (CVE-2014-0155)

2014-04-04T15:17:14+00:00

QE reported that they got the BUG_ON in ioapic_service to trigger.
I cannot reproduce it, but there are two reasons why this could happen.

The less likely but also easiest one, is when kvm_irq_delivery_to_apic
does not deliver to any APIC and returns -1.

Because irqe.shorthand == 0, the kvm_for_each_vcpu loop in that
function is never reached.  However, you can target the similar loop in
kvm_irq_delivery_to_apic_fast; just program a zero logical destination
address into the IOAPIC, or an out-of-range physical destination address.

Signed-off-by: Paolo Bonzini

KVM: ioapic: reinject pending interrupts on KVM_SET_IRQCHIP

2014-03-21T14:10:43+00:00

After the previous patches, an interrupt whose bit is set in the IRR
register will never be in the LAPIC's IRR and has never been injected
on the migration source.  So inject it on the destination.

This fixes migration of Windows guests without HPET (they use the RTC
to trigger the scheduler tick, and lose it after migration).

Reviewed-by: Alex Williamson 
Signed-off-by: Paolo Bonzini

KVM: ioapic: extract body of kvm_ioapic_set_irq

2014-03-21T09:20:16+00:00

We will reuse it to process a nonzero IRR that is passed to KVM_SET_IRQCHIP.

Reviewed-by: Alex Williamson 
Signed-off-by: Paolo Bonzini

KVM: ioapic: clear IRR for edge-triggered interrupts at delivery

2014-03-21T09:20:10+00:00

This ensures that IRR bits are set in the KVM_GET_IRQCHIP result only if
the interrupt is still sitting in the IOAPIC.  After the next patches, it
avoids spurious reinjection of the interrupt when KVM_SET_IRQCHIP is
called.

Reviewed-by: Alex Williamson 
Signed-off-by: Paolo Bonzini

KVM: ioapic: merge ioapic_deliver into ioapic_service

2014-03-21T09:19:48+00:00

Commonize the handling of masking, which was absent for kvm_ioapic_set_irq.
Setting remote_irr does not need a separate function either, and merging
the two functions avoids confusion.

Reviewed-by: Alex Williamson 
Signed-off-by: Paolo Bonzini

kvm: x86: ignore ioapic polarity

2014-03-13T10:58:21+00:00

Both QEMU and KVM have already accumulated a significant number of
optimizations based on the hard-coded assumption that ioapic polarity
will always use the ActiveHigh convention, where the logical and
physical states of level-triggered irq lines always match (i.e.,
active(asserted) == high == 1, inactive == low == 0). QEMU guests
are expected to follow directions given via ACPI and configure the
ioapic with polarity 0 (ActiveHigh). However, even when misbehaving
guests (e.g. OS X <= 10.9) set the ioapic polarity to 1 (ActiveLow),
QEMU will still use the ActiveHigh signaling convention when
interfacing with KVM.

This patch modifies KVM to completely ignore ioapic polarity as set by
the guest OS, enabling misbehaving guests to work alongside those which
comply with the ActiveHigh polarity specified by QEMU's ACPI tables.

Signed-off-by: Michael S. Tsirkin 
Signed-off-by: Gabriel L. Somlo 
[Move documentation to KVM_IRQ_LINE, add ia64. - Paolo]
Signed-off-by: Paolo Bonzini

kvm: make local functions static

2014-01-08T21:02:58+00:00

Running 'make namespacecheck' found lots of functions that
should be declared static, since only used in one file.

Signed-off-by: Stephen Hemminger 
Signed-off-by: Marcelo Tosatti

KVM: Set TMR when programming ioapic entry

2013-04-16T19:32:40+00:00

We already know the trigger mode of a given interrupt when programming
the ioapice entry. So it's not necessary to set it in each interrupt
delivery.

Signed-off-by: Yang Zhang 
Reviewed-by: Gleb Natapov 
Signed-off-by: Marcelo Tosatti

KVM: Call common update function when ioapic entry changed.

2013-04-16T19:32:40+00:00

Both TMR and EOI exit bitmap need to be updated when ioapic changed
or vcpu's id/ldr/dfr changed. So use common function instead eoi exit
bitmap specific function.

Signed-off-by: Yang Zhang 
Reviewed-by: Gleb Natapov 
Signed-off-by: Marcelo Tosatti