tree 5d7563cd69d710cf0948e48b26ff4b0cf197a51b
parent f6760aa024199cfbce564311dc4bc4d47b6fb349
author Avi Kivity <avi@redhat.com> 1262083336 +0200
committer Marcelo Tosatti <mtosatti@redhat.com> 1264429596 -0200

KVM: Fix race between APIC TMR and IRR

When we queue an interrupt to the local apic, we set the IRR before the TMR.
The vcpu can pick up the IRR and inject the interrupt before setting the TMR,
and perhaps even EOI it, causing incorrect behaviour.

The race is really insignificant since it can only occur on the first
interrupt (usually following interrupts will not change TMR), but it's better
closed than open.

Fixed by reordering setting the TMR vs IRR.

Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>