On Wed, Dec 7, 2022 at 3:58 PM Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx> wrote: > > On Tue, Dec 6, 2022 at 3:59 PM Benjamin Tissoires > <benjamin.tissoires@xxxxxxxxxx> wrote: > > > > As mentioned in the link below, having JIT and BPF is not enough to > > have fentry/fexit/fmod_ret APIs. This resolves the error that > > happens on a system without tracing enabled when hid-bpf tries to > > load itself. > > > > Link: https://lore.kernel.org/r/CABRcYmKyRchQhabi1Vd9RcMQFCcb=EtWyEbFDFRTc-L-U8WhgA@xxxxxxxxxxxxxx > > Fixes: f5c27da4e3c8 ("HID: initial BPF implementation") > > Signed-off-by: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx> > > > > --- > > > > no changes in v3 > > > > changes in v2: > > - dropped ALLOW_ERROR_INJECTION requirement > > Florent, can I keep your reviewed-by on this patch? Yes! :) Reviewed-by: Florent Revest <revest@xxxxxxxxxxxx> Thank you for the updated series, I think it's cleaner than relying on error injection indeed. I still believe that, in the future, BPF should offer a proxy config to expose if BPF tracing is supported because 1- the implementation of BPF tracing could someday change 2- to be exactly correct, ftrace direct call isn't _really_ a sufficient condition either: the BPF JIT also needs to implement the arch_prepare_bpf_trampoline function. Currently, there is no config to check if that feature is available. But as agreed in a previous thread, that consolidation can be done separately. For now your patch looks good enough to me already.
