On Mon, Nov 07, 2022 at 10:10:06PM +0100, Eric Auger wrote: > Hi Michael, > On 11/7/22 21:42, Michael S. Tsirkin wrote: > > On Mon, Nov 07, 2022 at 09:34:31PM +0100, Eric Auger wrote: > >> When the vhost iotlb is used along with a guest virtual iommu > >> and the guest gets rebooted, some MISS messages may have been > >> recorded just before the reboot and spuriously executed by > >> the virtual iommu after the reboot. Despite the device iotlb gets > >> re-initialized, the messages are not cleared. Fix that by calling > >> vhost_clear_msg() at the end of vhost_init_device_iotlb(). > >> > >> Signed-off-by: Eric Auger <eric.auger@xxxxxxxxxx> > >> --- > >> drivers/vhost/vhost.c | 1 + > >> 1 file changed, 1 insertion(+) > >> > >> diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c > >> index 40097826cff0..422a1fdee0ca 100644 > >> --- a/drivers/vhost/vhost.c > >> +++ b/drivers/vhost/vhost.c > >> @@ -1751,6 +1751,7 @@ int vhost_init_device_iotlb(struct vhost_dev *d, bool enabled) > >> } > >> > >> vhost_iotlb_free(oiotlb); > >> + vhost_clear_msg(d); > >> > >> return 0; > >> } > > Hmm. Can't messages meanwhile get processes and affect the > > new iotlb? > Isn't the msg processing stopped at the moment this function is called > (VHOST_SET_FEATURES)? > > Thanks > > Eric It's pretty late here I'm not sure. You tell me what prevents it. BTW vhost_init_device_iotlb gets enabled parameter but ignores it, we really should drop that. Also, it looks like if features are set with VIRTIO_F_ACCESS_PLATFORM and then cleared, iotlb is not properly cleared - bug? > > > > > >> -- > >> 2.37.3 _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
