Messages in this thread | | | Date | Wed, 17 Apr 2013 20:25:39 -0500 | From | Robin Holt <> | Subject | Re: [PATCH -v5 5/5] Make reboot_cpuid a kernel parameter. |
| |
On Wed, Apr 17, 2013 at 05:39:33PM -0700, H. Peter Anvin wrote: > On 04/17/2013 05:17 PM, Robin Holt wrote: > > > > There are 4 items being parsed out of reboot= for x86: > > - reboot_mode w[arm] | c[old] > > - reboot_cpu s[mp]#### > > - reboot_type b[ios] | a[cpi] | k[bd] | t[riple] | e[fi] | p[ci] > > - reboot_force f[orce] > > > > This seems like a lot to push into the generic kernel just to make it > > appear consistent when there will be no real cross arch consistency. > > > > Contrast that with: > > 1) New kernel parameter (reboot_cpu) which is clear and concise, uses standard > > parsing methods. > > 2) Backwards compatibility in that a user with an existing (broken) reboot=s32 > > on the command line will set reboot_cpu unless both were specified, in which > > case reboot_cpu takes precedence. > > > > What is so fundamentally wrong with that? It accomplishes exactly what > > you had asked for in that existing users are not broken. We are introducing > > a new functionality in the general kernel. Why not introduce a new parameter > > associated with that functionality. > > > > You are confusing implementation with interface. That is what is so > fundamentally wrong with that. You really, really don't want to change > interface unless the world will end if you don't. > > As far as why centralize -- the main concern I have is that someone > might try to introduce an arch-specific reboot= which is *syntactically* > different, which is yet again really awful from a user perspective.
Yes and no. I am saying that the interface is garbage and already specified as arch specific. You are asking me to take that garbage interface and promote it to a general interface which will force us to implement it in a completely crappy way.
Compare that with introducing a new interface which is concise and then providing backwards compatibility. Add to that the fact, I don't need to pollute the kernel with some poorly done x86 interface and leave that cruft for others to clean up.
Thanks, Robin
| |