On Thu, Oct 01, 2015 at 06:19:33PM +0300, Avi Kivity wrote: > On 10/01/2015 06:11 PM, Michael S. Tsirkin wrote: > >On Thu, Oct 01, 2015 at 02:32:19PM +0300, Avi Kivity wrote: > >>> We already agreed this kernel > >>>is going to be tainted, and unsupportable. > >>Yes. So your only motivation in rejecting the patch is to get the author to > >>write the ring translation patch and port it to all relevant drivers > >>instead? > >Not only that. > > > >To make sure users are aware they are doing insecure > >things when using software poking at device BARs in sysfs. > > I don't think you need to worry about that. People who program DMA are > aware of the damage is can cause.
People just install software and run it. They don't program DMA. And I notice that no software (ab)using this seems to come with documentation explaining the implications. > If you want to be extra sure, have uio > taint the kernel when bus mastering is enabled. People don't notice kernel is tainted. Denying module load will make them notice. -- MST
