On Mon, Apr 15, 2024 at 11:21 AM Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote: > > On Mon, 15 Apr 2024 at 11:11, Muhammad Usama Anjum > <usama.anjum@xxxxxxxxxxxxx> wrote: > > > > It isn't logical to wire up something which isn't present > > Actually, with system calls, the rules end up being almost opposite. > > There's no point in adding the code if it's not reachable. So adding > the system call code before adding the wiring makes no sense. > > So you have two cases: add the stubs first, or add the code first. > Neither does anything without the other. > > So then you go "add both in the same commit" option, which ends up > being horrible from a "review the code" standpoint. The two parts are > entirely different and mixing them up makes the patch very unclear > (and has very different target audiences for reviewing it - the MM > people really shouldn't have to look at the architecture wiring > parts). > > End result: there are no "this is the logical ordering" cases. > > But the "wire up system calls" part actually has some reasons to be first: > > - it reserves the system call number > > - it adds the "when system call isn't enabled, return -ENOSYS" > conditional system call logic > > so I actually tend prefer this ordering when it comes to system calls. > I confirm that the wire up change can be merged by its own, i.e. build will pass, and -ENOSYS will be returned at runtime. Thanks Linus for clarifying this. -Jeff > Linus
