Re: [PATCH 0/4] ftrace: One more check on x86 and some small fixes

From: Steven Rostedt
Date: Tue Jun 28 2016 - 15:18:04 EST


On Mon, 27 Jun 2016 15:54:33 +0200
Petr Mladek <pmladek@xxxxxxxx> wrote:

> 1st patch adds one more paranoid check of the modified function on x86.
>
> Plus there are 3 small changes that appeared when hunting down
> the 1st patch.
>
> Petr Mladek (4):
> ftrace/x86: Make sure to modify 5-bite instructions
> ftrace/x86: Do not crash when reading wrong ftrace func

The first two are mostly just "detect error, when it happens again"
chanes.

> ftrace: Always destroy trampoline when shutting down the trace
> ftrace: Fixup trace_selftest_ops()

These two seem to fix real bugs. I'm thinking they should go in now and
be backported via stable.

Thoughts?

-- Steve

>
> arch/x86/kernel/ftrace.c | 12 ++++++++-
> kernel/trace/ftrace.c | 62 ++++++++++++++++++++++---------------------
> kernel/trace/trace_selftest.c | 7 ++---
> 3 files changed, 47 insertions(+), 34 deletions(-)
>