diff options
| -rw-r--r-- | src/cpu/kvm/base.cc | 7 | ||||
| -rw-r--r-- | src/cpu/kvm/base.hh | 10 | ||||
| -rw-r--r-- | src/cpu/kvm/x86_cpu.cc | 7 |
3 files changed, 16 insertions, 8 deletions
diff --git a/src/cpu/kvm/base.cc b/src/cpu/kvm/base.cc index 6ea99ce4a..d0f7515de 100644 --- a/src/cpu/kvm/base.cc +++ b/src/cpu/kvm/base.cc @@ -1147,10 +1147,9 @@ BaseKvmCPU::doMMIOAccess(Addr paddr, void *data, int size, bool write) delete pkt; return clockPeriod() * ipr_delay; } else { - // Temporarily lock and migrate to the event queue of the - // VM. This queue is assumed to "own" all devices we need to - // access if running in multi-core mode. - EventQueue::ScopedMigration migrate(vm.eventQueue()); + // Temporarily lock and migrate to the device event queue to + // prevent races in multi-core mode. + EventQueue::ScopedMigration migrate(deviceEventQueue()); return dataPort.submitIO(pkt); } diff --git a/src/cpu/kvm/base.hh b/src/cpu/kvm/base.hh index 29872e744..a22637f98 100644 --- a/src/cpu/kvm/base.hh +++ b/src/cpu/kvm/base.hh @@ -419,6 +419,16 @@ class BaseKvmCPU : public BaseCPU void syncThreadContext(); /** + * Get a pointer to the event queue owning devices. + * + * Devices always live in a separate device event queue when + * running in multi-core mode. We need to temporarily migrate to + * this queue when accessing devices. By convention, devices and + * the VM use the same event queue. + */ + EventQueue *deviceEventQueue() { return vm.eventQueue(); } + + /** * Update the KVM if the thread context is dirty. */ void syncKvmState(); diff --git a/src/cpu/kvm/x86_cpu.cc b/src/cpu/kvm/x86_cpu.cc index bdbdadf71..467e1baaf 100644 --- a/src/cpu/kvm/x86_cpu.cc +++ b/src/cpu/kvm/x86_cpu.cc @@ -1346,10 +1346,9 @@ X86KvmCPU::handleKvmExitIO() } const MemCmd cmd(isWrite ? MemCmd::WriteReq : MemCmd::ReadReq); - // Temporarily lock and migrate to the event queue of the - // VM. This queue is assumed to "own" all devices we need to - // access if running in multi-core mode. - EventQueue::ScopedMigration migrate(vm.eventQueue()); + // Temporarily lock and migrate to the device event queue to + // prevent races in multi-core mode. + EventQueue::ScopedMigration migrate(deviceEventQueue()); for (int i = 0; i < count; ++i) { RequestPtr io_req = new Request(pAddr, kvm_run.io.size, Request::UNCACHEABLE, dataMasterId()); |