On Fri, Jul 10, 2020 at 11:03:44AM +0200, Peter Zijlstra wrote: > On Fri, Jul 10, 2020 at 02:45:19AM +0300, Jarkko Sakkinen wrote: > > Remove MODULES dependency and migrate from module_alloc to vmalloc(). > > According to Andi, the history with this dependency is that kprobes > > originally required custom LKM's, which does not hold today anymore. > > > > Right now one has to compile LKM support only to enable kprobes. With > > this change applied, it is somewhat easier to create custom test > > kernel's with a proper debugging capabilities, thus making Linux more > > developer friendly. > > > > Cc: Andi Kleen <[email protected]> > > Signed-off-by: Jarkko Sakkinen <[email protected]> > > NAK > > this patch is horrific, it sprinkles a metric ton of #ifdef and silently > disables a lot of kprobe features (like all the opt stuff).
Perfectly nderstandable. I just drafted something quick andy dirty together for idea's sake (and put RFC tag to state that). The application where I use this chhange, is when I refactor large patch set that I'm working on (namely SGX patch set in my case). I just want squeece all the extra out from the kernel build and still have means for instrumentation. A static kernel is very convenient for this kind of purpose, as with EFI stub and statically linked user space you can have a single test binary. > How about unconditionally providing module_alloc() instead? I believe so, yes. Just so that I know (and learn), what did exactly disable optprobes? Not too familiar with this part of the kernel - that's why I'm asking. Does the module_alloc to vmalloc change disable it? /Jarkko
