Hi Jens, >> I know you brought this one up as part of your series, not sure I get >> why you want it owned by root and read-only? cmdline and exe, yeah those >> could be hidden, but is there really any point? >> >> Maybe I'm missing something here, if so, do clue me in! > > I looked through /proc and I think it's mostly similar to > the unshare() case, if userspace wants to do stupid things > like changing "comm" of iothreads, it gets what was asked for. > > But the "cmdline" hiding would be very useful. > > While most tools use "comm", by default. > > ps -eLf or 'iotop' use "cmdline". > > Some processes use setproctitle to change "cmdline" in order > to identify the process better, without the 15 chars comm restriction, > that's why I very often press 'c' in 'top' to see the cmdline, > in that case it would be very helpful to see '[iou-wrk-1234]' > instead of the seeing the cmdline. > > So I'd very much prefer if this could be applied: > https://lore.kernel.org/io-uring/d4487f959c778d0b1d4c5738b75bcff17d21df5b.1616197787.git.metze@xxxxxxxxx/T/#u > > If you want I can add a comment and a more verbose commit message... I noticed that 'iotop' actually appends ' [iou-wrk-1234]' to the cmdline value, so that leaves us with 'ps -eLf' and 'top' (with 'c'). pstree -a -t -p is also fine: │ └─io_uring-cp,1315 /root/kernel/linux-image-5.12.0-rc2+-dbg_5.12.0-rc2+-5_amd64.deb file │ ├─{iou-mgr-1315},1316 │ ├─{iou-wrk-1315},1317 │ ├─{iou-wrk-1315},1318 │ ├─{iou-wrk-1315},1319 │ ├─{iou-wrk-1315},1320 In the spirit of "avoid special PF_IO_WORKER checks" I guess it's ok to leave of as is... metze
