On Tue 24-04-18 11:50:30, Mikulas Patocka wrote: > > > On Tue, 24 Apr 2018, Michal Hocko wrote: > > > On Mon 23-04-18 20:06:16, Mikulas Patocka wrote: > > [...] > > > @@ -404,6 +405,12 @@ void *kvmalloc_node(size_t size, gfp_t f > > > */ > > > WARN_ON_ONCE((flags & GFP_KERNEL) != GFP_KERNEL); > > > > > > +#ifdef CONFIG_DEBUG_SG > > > + /* Catch bugs when the caller uses DMA API on the result of kvmalloc. */ > > > + if (!(prandom_u32_max(2) & 1)) > > > + goto do_vmalloc; > > > +#endif > > > > I really do not think there is anything DEBUG_SG specific here. Why you > > simply do not follow should_failslab path or even reuse the function? > > CONFIG_DEBUG_SG is enabled by default in RHEL and Fedora debug kernel (if > you don't like CONFIG_DEBUG_SG, pick any other option that is enabled > there).
Are you telling me that you are shaping a debugging functionality basing on what RHEL has enabled? And you call me evil. This is just rediculous. > Fail-injection framework is if off by default and it must be explicitly > enabled and configured by the user - and most users won't enable it. It can be enabled easily. And if you care enough for your debugging kernel then just make it enabled unconditionally. -- Michal Hocko SUSE Labs