Re: [LTP] [PATCH v2] syscall/ptrace08: Simplify the test.

From: Cyril Hrubis
Date: Fri Sep 04 2020 - 11:53:27 EST


Hi!
> + /*
> + * The original fix for the kernel haven't rejected the kernel address
> + * right away when breakpoint was modified from userspace it was
> + * disabled and the EINVAL was returned when dr7 was written to enable
> + * it again.
> + */
> + if (tst_kvercmp(4, 17, 0) < 0)
> + deffered_check = 1;

And this should be 4.19 as the modify_user_hw_breakpoint_check() was made
uncoditional (by accident) in:

commit bd14406b78e6daa1ea3c1673bda1ffc9efdeead0
Author: Jiri Olsa <jolsa@xxxxxxxxxx>
Date: Mon Aug 27 11:12:25 2018 +0200

perf/hw_breakpoint: Modify breakpoint even if the new attr has disabled set


--
Cyril Hrubis
chrubis@xxxxxxx