Hi Dominique, On 2018/8/8 17:40, Dominique Martinet wrote: > piaojun wrote on Wed, Aug 08, 2018: >> I try to remove 9pnet_virtio.ko by 'rmmod 9pnet_virtio' as I want to >> replace it without rebooting system. > > I do that all the time when testing, it works for me. > What exact kernel commit are you running? > My kernel commit id 6edf1d4cb0acde, and I replace the 9p code with 9p-next. And I wonder if this will work well?
>> Here I have not mount 9pfs yet, so the refcount is still 0. >> >> Before rmmod: >> # lsmod | grep 9p >> 9pnet_virtio 20480 0 >> 9pnet 106496 1 9pnet_virtio >> virtio_ring 28672 5 >> virtio_scsi,9pnet_virtio,virtio_pci,virtio_blk,virtio_net >> virtio 16384 5 >> virtio_scsi,9pnet_virtio,virtio_pci,virtio_blk,virtio_net >> >> After rmmod: >> # lsmod | grep 9p >> 9pnet_virtio 20480 0 >> 9pnet 106496 1 9pnet_virtio >> virtio_ring 28672 5 >> virtio_scsi,9pnet_virtio,virtio_pci,virtio_blk,virtio_net >> virtio 16384 5 >> virtio_scsi,9pnet_virtio,virtio_pci,virtio_blk,virtio_net >> >> Normally 9pnet_virtio should be invisible after rmmod like this: >> # lsmod | grep 9p >> 9pnet 106496 0 > > Right, that obviously didn't work... > > But on the other hand, if I apply your commit and load/unload > 9pnet_virtio 5-10 times (I ran it in a loop) I get KASAN errors because > we put too many of these refs ; that doesn't happen without your patch > so it's apparently wrong. > I'm curious how that could make modprobe work better for you as well, it > shouldn't depend on that... > > Maybe `modprobe -r` might give a better error, or something in dmesg? > In my testing, `modprobe -r` has the same behavior with rmmod.
