On Mon, Dec 05, 2022 at 07:22:44AM +0900, Masami Hiramatsu (Google) wrote: > From: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx> > > Since the function error injection framework in the fault injection > subsystem can change the function code flow forcibly, it may cause > unexpected behavior (and that is the purpose of this feature) even > if it is applied to the ALLOW_ERROR_INJECTION functions. > So this feature must be used only for debugging or testing purpose. The whole idea of tainting for kernel debugging is questionable. There are many other *inject* kconfigs and other debug flags for link lists, RCU, sleeping, etc. None of them taint the kernel. > To identify this in the kernel oops message, add a new taint flag Have you ever seen a single oops message because of this particular error injection? > for the fault injection. This taint flag will be set by either > function error injection is used or the BPF use the kprobe_override > on error injectable functions (identified by ALLOW_ERROR_INJECTION). ... > /* set the new array to event->tp_event and set event->prog */ > + if (prog->kprobe_override) > + add_taint(TAINT_FAULT_INJECTED, LOCKDEP_NOW_UNRELIABLE); Nack for bpf bits.
