gwj / at91sam9263 · Commits

Commit 8c14c17395809dfb2b20bd3598e067d2c5af7dc4

Authored by Jan Kiszka
Committed by Anthony Liguori
1 parent 6a7ad299

kvm: Fix IRQ injection into full queue 

User space may only inject interrupts during kvm_arch_pre_run if
ready_for_interrupt_injection is set in kvm_run. But that field is
updated on exit from KVM_RUN, so we must ensure that we enter the
kernel after potentially queuing an interrupt, otherwise we risk to
loose one - like it happens with the current code against latest
kernel modules (since kvm-86) that started to queue only a single
interrupt.

Fix the problem by reordering kvm_cpu_exec.

Credits go to Gleb Natapov for analyzing the issue in details.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Inline Side-by-side
Showing 1 changed file with 1 additions and 2 deletions
kvm-all.c
  View file @8c14c17
... ... @@ -578,14 +578,13 @@ int kvm_cpu_exec(CPUState *env)
578 578 dprintf("kvm_cpu_exec()\n");
579 579  
580 580 do {
581   - kvm_arch_pre_run(env, run);
582   -
583 581 if (env->exit_request) {
584 582 dprintf("interrupt exit requested\n");
585 583 ret = 0;
586 584 break;
587 585 }
588 586  
  587 + kvm_arch_pre_run(env, run);
589 588 ret = kvm_vcpu_ioctl(env, KVM_RUN, 0);
590 589 kvm_arch_post_run(env, run);
591 590  
... ...