Messages in this thread | | | Date | Fri, 11 Jul 2014 11:26:34 +0900 | From | Masami Hiramatsu <> | Subject | Re: [RFC][PATCH 0/3] ftrace: Add dynamically allocated trampolines |
| |
(2014/07/11 6:44), Jiri Kosina wrote: > On Thu, 10 Jul 2014, Josh Poimboeuf wrote: > >> I did some testing with kpatch and I found one minor issue. The dynamically >> allocated trampoline seems to confuse dump_stack() somewhat. >> >> I added a dump_stack() call in my ftrace_ops callback function >> (kpatch_ftrace_handler) which had a filter on meminfo_proc_show(). > > Interesting. Are you using dwarf2 unwinder for stack dumping by any > chance? It seems to get things right here. Will look into it more > tomorrow.
Hmm, can dwarf2 unwinder work on the trampoline method? Since the trampoline just a copy of instructions which will not have CFI(which is stored in dwarf section), I guess it may not work... Frame pointer (push bp and save sp to bp on the entry) can work anyway.
Thank you,
-- Masami HIRAMATSU Software Platform Research Dept. Linux Technology Research Center Hitachi, Ltd., Yokohama Research Laboratory E-mail: masami.hiramatsu.pt@hitachi.com
| |