> From: Jason Gunthorpe <jgg@xxxxxxxxxx> > Sent: Friday, January 20, 2023 10:34 PM > > On Fri, Jan 20, 2023 at 02:00:26PM +0000, Liu, Yi L wrote: > > Say in the same time, we have thread B closes device, it will hold > > group_lock first and then calls kvm_put_kvm() which is the last > > reference, then it would loop the kvm-device list. Currently, it is > > not holding kvm_lock. But it also manipulating the kvm-device list, > > should it hold kvm_lock? > > No. When using refcounts if the refcount is 0 it guarantees there are > no other threads that can possibly touch this memory, so any locks > internal to the memory are not required. Ok. The patch has been sent out standalone. https://lore.kernel.org/kvm/20230114000351.115444-1-mjrosato@xxxxxxxxxxxxx/T/#u Regards, Yi Liu
