* David Miller <[email protected]> wrote:
> From: Josef Bacik <[email protected]>
> Date: Tue, 7 Nov 2017 15:28:41 -0500
>
> > I'm sending this through Dave since it'll conflict with other BPF changes
> > in his
> > tree, but since it touches tracing as well Dave would like a review from
> > somebody on the tracing side.
> ...
> > A lot of our error paths are not well tested because we have no good way of
> > injecting errors generically. Some subystems (block, memory) have ways to
> > inject errors, but they are random so it's hard to get reproduceable
> > results.
> >
> > With BPF we can add determinism to our error injection. We can use kprobes
> > and
> > other things to verify we are injecting errors at the exact case we are
> > trying
> > to test. This patch gives us the tool to actual do the error injection
> > part.
> > It is very simple, we just set the return value of the pt_regs we're given
> > to
> > whatever we provide, and then override the PC with a dummy function that
> > simply
> > returns.
> >
> > Right now this only works on x86, but it would be simple enough to expand to
> > other architectures. Thanks,
>
> Series applied, thanks Josef.
Please don't apply it yet as the series is still under active discussion - for
now
I'm NAK-ing the x86 bits because I have second thoughts about the whole premise
of
the feature being added here.
Thanks,
Ingo
