On Fri, Jul 6, 2018 at 7:31 PM Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote: > > Who actually does direct read/write to /dev/sg? Could we perhaps just > add a config option to disable it entirely? On the IB side, the argument was that there was some crazy binary-only vendor management code that really wanted to use this completely crazy interface. I also think that the warnings are dubious. I'd rather add a deprecation warning to the whole "read/write to /dev/sg" itself, and then do what we did for ib_safe_file_access(), which was to just have the permission checks. It's not like a normal person should have access to /dev/sg to begin with. So it's not like you can open /dev/sg0 and then try to fool a suid program into doing the actual IO. I'd hope. Maybe I'm wrong, and there's some crazy "let's make /dev/sg available to normal users" setup out there somewhere. At least for me, /dev/sg isn't accessible to normal people: [torvalds@i7 linux]$ cat /dev/sg0 cat: /dev/sg0: Permission denied but maybe some distro decided that everybody should have direct device access.. Jann? Linus