On Fri, Feb 25, 2022 at 08:40:36PM -0500, Theodore Ts'o wrote: > Well, that makes it process_vm_writev()'s is that it needs to know > when to call pin_user_file_pages(). Sorry, typed too fast. What I was trying to say is this make it process_vm_writev()'s problem to figure out when it should call pin_user_file_pages() versus some other pin_user_pages function. > I suspect that for many use cases > --- for example, if this is being used by a debugger to modify a > variable on a stack, or an anonymous page in the program's data > segment, process_vm_writev() *isn't* actually pinning a file. So they > want some kind of interface that automatically DTRT regardless of > whether the user pages being edited are file-backed or not > file-backed. - Ted
