Re: [PATCH 2/2] perf tests: Add a test for the ARM 32-bit [vectors] page

From: Andrew Lunn
Date: Wed Oct 24 2018 - 22:15:59 EST


On Wed, Oct 24, 2018 at 05:09:05PM -0700, Florian Fainelli wrote:
> perf on ARM requires CONFIG_KUSER_HELPERS to be turned on to allow some
> independance with respect to the ARM CPU being used. Add a test which
> tries to locate the [vectors] page, created when CONFIG_KUSER_HELPERS is
> turned on to help asses the system's health.

Hi Florian

I've suffered the pain from missing CONFIG_KUSER_HELPERS. The
segfaults give little clue as to what is going wrong,and gdb is not
much use either.

What i don't see here is any clue to CONFIG_KUSER_HELPERS. If the test
fails, could you print a message suggesting CONFIG_KUSER_HELPERS on
ARM?

Andrew