> On Mar 19, 2019, at 10:33 PM, Jerome Glisse <jglisse@xxxxxxxxxx> wrote: > > So i believe best we could do is send a SIGBUS to the process that has > GUPed a range of a file that is being truncated this would match what > we do for CPU acces. There is no reason access through GUP should be > handled any differently. This should be done lazily, as there's no need to send the SIGBUS unless the GUPed page is actually accessed post-truncate.