On Sat, Oct 31, 2020 at 12:42 AM Guo Ren <guoren@xxxxxxxxxx> wrote: > > On Sat, Oct 31, 2020 at 8:28 AM Steven Rostedt <rostedt@xxxxxxxxxxx> wrote: > > > > On Fri, 30 Oct 2020 14:47:56 -0700 > > Atish Patra <atishp@xxxxxxxxxxxxxx> wrote: > > > > > > Look at arm64, they __kprobes flag and I guess it would also prevent > > > > ftrace call site. > > > > > > > > > > Are you sure about that ? __kprobes puts the code in .kprobes.text section > > > which is under whitelist sections in recordmcount.pl & recordmcount.c. > > > > Correct, ftrace can trace functions marked with __kprobes. That said, > I guess wrong, thx for correct me. > > > the instruction you are looking at here, is in a file that is > > blacklisted from recordmcount. > > > > CFLAGS_REMOVE_insn.o = $(CC_FLAGS_FTRACE) > > > > All ftrace flags are removed from the compiling of insn.c, and every > > function in that file will not be traced. > Yes, arm64 prevents the whole file from ftrace. My patch just use > notrace flag setting on some functions. > > @Atish How do think: > CFLAGS_REMOVE_cacheflush.o = $(CC_FLAGS_FTRACE) > CFLAGS_REMOVE_sbi.o = $(CC_FLAGS_FTRACE) > Looks good to me. What should be done for copy_to_kernel_nofault ? That is also in the calling path. > -- > Best Regards > Guo Ren > > ML: https://lore.kernel.org/linux-csky/ -- Regards, Atish