[bug report][stable] perf probe: failed to add events

Joseph Qi
2019-02-26T07:31:34Z

Hi,

I'm using kernel v4.19.24 and have found that there is an issue when
using perf probe to define a new dynamic tracepoint.

$ perf probe -a handle_mm_fault
Failed to write event: Numerical result out of range
Error: Failed to add events.

I've also tried kernel v4.20, and it can pass.

So I've bisected and finally found the first good commit is:
bf904d2762ee x86/pti/64: Remove the SYSCALL64 entry trampoline
which is based on another commit:
98f05b5138f0 Use the TSS sp2 slot for SYSCALL/SYSRET scratch space

Once I've backpoted these two commits into 4.19.24, the above case can
pass, though I'm not sure how it is fixed.
So is there any plan to let them go into stable as well?

Thanks,
Joseph