Re: [RFC PATCH 00/35] remove in-kernel syscall invocations

From: Dominik Brodowski
Date: Mon Mar 12 2018 - 17:42:24 EST


On Sun, Mar 11, 2018 at 01:15:59PM -0700, Linus Torvalds wrote:
> On Sun, Mar 11, 2018 at 3:55 AM, Dominik Brodowski
> <linux@xxxxxxxxxxxxxxxxxxxx> wrote:
> > Here is a first set of patches which reduce the number of syscall invocations
> > from within the kernel.
>
> This all looks ok to me. I think there may be some room for cleanup
> and bikeshedding later (the "ksys_mmap_pgoff()" name made me go "that
> sounds more like a real helper than a kernel syscall", for example),
> but on the whole I think it's best to start with this kind of fairly
> direct translation.
>
> In fact, because it all looks *so* mechanical, I'd even be willing to
> just pull this into 4.16, if that makes the real work that this
> depends on easier?
>
> Anyway, ack from me, qith the only question being how you want to
> handle the patches. Direct pull request to me, go through the -mm
> tree, or just keep them in your own git tree and then build upon it
> and send it all later?

Thanks for your feedback! As I think this deserves at least another round of
review and some testing by 0day, I've set up a git tree at

https://git.kernel.org/pub/scm/linux/kernel/git/brodo/linux syscalls-next

This will allow me to re-base and tweak the patches for a while, and add
some more similar patches on top. For example, besides the first set of
35+1 patches in the aforementioned branch "syscalls-next" there are a few
other patches -- including one you might find familiar -- in "syscalls-WIP"
which are not fully ready yet.

The patches in that repository also include the following changes since
yesterday's RFC:

- rebase to v4.15-rc5
- sys_ioperm already got its SYSCALL_DEFINE3

- add ACK from Richard Weinberger

- modify CC -> Cc (suggested by Ingo Molnar)

- update comment in include/linux/syscalls.h (suggested by Ingo Molnar and
Andy Lutomirski)

- separate declarations from definitions with newlines in
include/linux/syscalls.h; add comment on ksys_close() (suggested by
Ingo Molnar)

- expand commit messages (suggested by Christoph Hellwig)

- add patch 36: fs: add ksys_open() wrapper; remove in-kernel calls to
sys_open()

Thanks,
Dominik