On 11.11.2018 2:30, Steven Rostedt wrote: > On Sun, 11 Nov 2018 01:05:30 +0300 > Alexander Popov <alex.po...@linux.com> wrote: > >> The stackleak_erase() function is called on the trampoline stack at the >> end of syscall. This stack is not big enough for ftrace operations, >> e.g. it can be overflowed if we enable kprobe_events for stackleak_erase(). > > Is the issue with kprobes or with function tracing? Because this stops > function tracing which I only want disabled if function tracing itself > is an issue, not for other things that may use the function tracing > infrastructure.
Hello Steven, I believe that stackleak erasing is not compatible with function tracing itself. That's what the kernel testing robot has hit: https://www.openwall.com/lists/kernel-hardening/2018/11/09/1 I used kprobe_events just to reproduce the problem: https://www.openwall.com/lists/kernel-hardening/2018/11/09/4 Best regards, Alexander
