linux-kernel - Re: [RFC] systemtap: begin the process of using proper kernel APIs (part1: use kprobe symbol

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 18 Jul 2008 09:02:19 -0400
From:	fche@...hat.com (Frank Ch. Eigler)
To:	Peter Zijlstra <peterz@...radead.org>
Cc:	Andi Kleen <andi@...stfloor.org>,
	James Bottomley <James.Bottomley@...senPartnership.com>,
	linux-kernel <linux-kernel@...r.kernel.org>,
	systemtap@...rceware.org, jbeulich@...ell.com
Subject: Re: [RFC] systemtap: begin the process of using proper kernel APIs 	(part1: use kprobe symbol_name/offset instead of address)

Peter Zijlstra <peterz@...radead.org> writes:

> [...]
>> Right now x86 doesn't really have a good reliable unwinder that
>> works without frame pointer. I think systemtap
>> recently switched to Jan Beulich's dwarf2 unwinder. Before
>> switching to the in kernel unwinder that one would need to be 
>> re-merged again.
>
> Those are two separate issues.
>
> 1) stap ought to use the kernel's infrastructure and not re-implement
> its own.
> 2) if the kernel's infrastructure doesn't meet requirements, improve
> it.

They are related to the extent that readers may not realize some
implications of systemtap being/becoming a *kernel-resident* but not
*kernel-focused* tool.

For example, we're about to do unwinding/stack-traces of userspace
programs.  To what extent do you think the kernel unwinder (should one
reappear in git) would welcome patches that provide zero benefit to
the kernel, but only enable a peculiar (nonintrusive) sort of
unwinding we would need for complex userspace stacks?

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