This is the mail archive of the
systemtap@sourceware.org
mailing list for the systemtap project.
Re: arm64 kprobes patches
- From: Sandeepa Prabhu <sandeepa dot prabhu at linaro dot org>
- To: "Frank Ch. Eigler" <fche at redhat dot com>
- Cc: systemtap at sourceware dot org, William Cohen <wcohen at redhat dot com>, Masami Hiramatsu <masami dot hiramatsu dot pt at hitachi dot com>, Petr Machata <pmachata at redhat dot com>, Mark Wielaard <mjw at redhat dot com>, Deepak Saxena <dsaxena at linaro dot org>, Arnd Bergmann <arnd dot bergmann at linaro dot org>, "sandeepa dot prabhu at linux dot com" <sandeepa dot prabhu at linux dot com>
- Date: Thu, 27 Feb 2014 10:12:26 +0530
- Subject: Re: arm64 kprobes patches
- Authentication-results: sourceware.org; auth=none
- References: <CA+b37P175OWKXcQ-4SYb+AudxOJMe3OC5csoZognNuX7MOaTyQ at mail dot gmail dot com> <y0mzjldal1o dot fsf at fche dot csb>
On 26 February 2014 22:06, Frank Ch. Eigler <fche@redhat.com> wrote:
> Sandeepa Prabhu <sandeepa.prabhu@linaro.org> writes:
>
>> Hi all,
>> We have uploaded arm64 kprobes latest changes on linaro git which
>> include some fixes for recursive kprobes. [...]
>
> Great.
>
>> Please let us know if you are interested in pulling this branch for
>> systemtap test-suite verification, while we are trying to include
>> systemtap test-suite on our linaro open-embedded platforms.
>
> We will try soon.
Thanks, we will start verifying from our end too.
>
>> Also, please let us know if there are documentation on howto run full
>> test-suite for systemtap and various criteria kprobes should meet?
>
> The systemtap README includes these words:
>
> [...]
> To run a simple test.
> # stap -v -e 'probe vfs.read {printf("read performed\n"); exit()}'
>
> To run the full test suite from the build tree.
> # make installcheck
> [...]
>
> The full installcheck suite exercises kprobes some, but not in a
> stressful mode, like
>
> probe kernel.function("*").* {}
>
> That's partly because the x86 kernel has never been able to survive
> such a test. It would be great if arm kprobes were robust enough.
Even on arm64, there are kernel functions that fails for kprobes,
(example: memcpy, memset etc) that are referenced by kprobe handler
themselves.
>
>
> - FChE