Re: [RFA][PATCH 2/5] ftrace/x86: One more missing sync after fixup of function modification failure

From: Steven Rostedt
Date: Thu Feb 27 2014 - 11:05:50 EST


H. Peter, I forgot to Cc you on this one. As you are the one I'm
looking for an Ack from.

-- Steve


On Thu, 27 Feb 2014 10:46:18 -0500
Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:

> [Request for Ack]
>
> From: Petr Mladek <pmladek@xxxxxxx>
>
> If a failure occurs while modifying ftrace function, it bails out and will
> remove the tracepoints to be back to what the code originally was.
>
> There is missing the final sync run across the CPUs after the fix up is done
> and before the ftrace int3 handler flag is reset.
>
> Link: http://lkml.kernel.org/r/1393258342-29978-2-git-send-email-pmladek@xxxxxxx
>
> Fixes: 8a4d0a687a5 "ftrace: Use breakpoint method to update ftrace caller"
> Cc: stable@xxxxxxxxxxxxxxx # 3.5+
> Signed-off-by: Petr Mladek <pmladek@xxxxxxx>
> Signed-off-by: Steven Rostedt <rostedt@xxxxxxxxxxx>
> ---
> arch/x86/kernel/ftrace.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
> index 6b566c8..69885e2 100644
> --- a/arch/x86/kernel/ftrace.c
> +++ b/arch/x86/kernel/ftrace.c
> @@ -660,8 +660,8 @@ ftrace_modify_code(unsigned long ip, unsigned const char *old_code,
> ret = -EPERM;
> goto out;
> }
> - run_sync();
> out:
> + run_sync();
> return ret;
>
> fail_update:

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/