From: Josef Bacik <jo...@toxicpanda.com> 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.
