linux-toradex.git/virt/kvm/assigned-dev.c, branch v2.6.33.2 Linux kernel for Apalis and Colibri modules KVM: Fix possible circular locking in kvm_vm_ioctl_assign_device() 2009-12-27T15:36:31+00:00 Sheng Yang sheng@linux.intel.com 2009-12-15T02:28:07+00:00 fae3a3536a6fecedebd49fa847f810e599bfb132 One possible order is: KVM_CREATE_IRQCHIP ioctl(took kvm->lock) -> kvm_iobus_register_dev() -> down_write(kvm->slots_lock). The other one is in kvm_vm_ioctl_assign_device(), which take kvm->slots_lock first, then kvm->lock. Update the comment of lock order as well. Observe it due to kernel locking debug warnings. Cc: stable@kernel.org Signed-off-by: Sheng Yang <sheng@linux.intel.com> Signed-off-by: Avi Kivity <avi@redhat.com> 
One possible order is:

KVM_CREATE_IRQCHIP ioctl(took kvm->lock) -> kvm_iobus_register_dev() ->
down_write(kvm->slots_lock).

The other one is in kvm_vm_ioctl_assign_device(), which take kvm->slots_lock
first, then kvm->lock.

Update the comment of lock order as well.

Observe it due to kernel locking debug warnings.

Cc: stable@kernel.org
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
KVM: Move assigned device code to own file 2009-12-03T07:32:09+00:00 Avi Kivity avi@redhat.com 2009-08-26T11:57:50+00:00 bfd99ff5d483b11c32bca49fbff7a5ac59038b0a Signed-off-by: Avi Kivity <avi@redhat.com> 
Signed-off-by: Avi Kivity <avi@redhat.com>