Re: [PATCH v5 1/6] kprobes: Remove dependency to the module_mutex

[Jarkko Sakkinen]

On Fri, Jul 24, 2020 at 01:22:58PM +0300, Mike Rapoport wrote:
> On Fri, Jul 24, 2020 at 08:05:48AM +0300, Jarkko Sakkinen wrote:
> > Add lock_modules() and unlock_modules() wrappers for acquiring module_mutex
> > in order to remove the compile time dependency to it.
> > 
> > Cc: linux-mm@xxxxxxxxx
> > Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
> > Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
> > Suggested-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
> > Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
> > ---
> >  include/linux/module.h      | 18 ++++++++++++++++++
> >  kernel/kprobes.c            |  4 ++--
> >  kernel/trace/trace_kprobe.c |  4 ++--
> >  3 files changed, 22 insertions(+), 4 deletions(-)
> 
> Any reason to convert only kprobes to the new API and leave others with
> opencoded implementation?

Not anything particular.

Lets see:

$ git --no-pager grep "mutex_lock(&module_mutex)"
arch/powerpc/platforms/powernv/pci-cxl.c:       mutex_lock(&module_mutex);
drivers/gpu/drm/drm_fb_helper.c:        mutex_lock(&module_mutex);
include/linux/module.h: mutex_lock(&module_mutex);
kernel/livepatch/core.c:        mutex_lock(&module_mutex);
kernel/livepatch/core.c:        mutex_lock(&module_mutex);
kernel/module.c:        mutex_lock(&module_mutex);
kernel/module.c:        mutex_lock(&module_mutex);
kernel/module.c:        mutex_lock(&module_mutex);
kernel/module.c:        mutex_lock(&module_mutex);
kernel/module.c:        mutex_lock(&module_mutex);
kernel/module.c:        mutex_lock(&module_mutex);
kernel/module.c:        mutex_lock(&module_mutex);
kernel/module.c:        mutex_lock(&module_mutex);
kernel/module.c:        mutex_lock(&module_mutex);
kernel/module.c:        mutex_lock(&module_mutex);
kernel/module.c:        mutex_lock(&module_mutex);
kernel/module.c:        mutex_lock(&module_mutex);
kernel/module.c:        mutex_lock(&module_mutex);

I could refine this commit to patch these sites. Or should I split it
into multiple?

/Jarkko