Merge tag 'trace-v4.11-rc5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull ftrace fix from Steven Rostedt: "While rewriting the function probe code, I stumbled over a long standing bug. This bug has been there sinc function tracing was added way back when. But my new development depends on this bug being fixed, and it should be fixed regardless as it causes ftrace to disable itself when triggered, and a reboot is required to enable it again. The bug is that the function probe does not disable itself properly if there's another probe of its type still enabled. For example: # cd /sys/kernel/debug/tracing # echo schedule:traceoff > set_ftrace_filter # echo do_IRQ:traceoff > set_ftrace_filter # echo \!do_IRQ:traceoff > /debug/tracing/set_ftrace_filter # echo do_IRQ:traceoff > set_ftrace_filter The above registers two traceoff probes (one for schedule and one for do_IRQ, and then removes do_IRQ. But since there still exists one for schedule, it is not done properly. When adding do_IRQ back, the breakage in the accounting is noticed by the ftrace self tests, and it causes a warning and disables ftrace" * tag 'trace-v4.11-rc5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: ftrace: Fix removing of second function probe
Please register or sign in to comment