linux-mips
[Top] [All Lists]

Re: [PATCH 2/4] MIPS Kprobes: Deny probes on ll/sc instructions

To: Victor Kamensky <kamensky@cisco.com>
Subject: Re: [PATCH 2/4] MIPS Kprobes: Deny probes on ll/sc instructions
From: Ralf Baechle <ralf@linux-mips.org>
Date: Wed, 16 Nov 2011 12:12:07 +0000
Cc: David Daney <david.daney@cavium.com>, "manesoni@cisco.com" <manesoni@cisco.com>, "ananth@in.ibm.com" <ananth@in.ibm.com>, "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>, "linux-mips@linux-mips.org" <linux-mips@linux-mips.org>
In-reply-to: <Pine.GSO.4.58.1111081504560.10959@infra-view9.cisco.com>
References: <20111108170336.GA16526@cisco.com> <20111108170535.GC16526@cisco.com> <4EB98A8E.4060900@cavium.com> <Pine.GSO.4.58.1111081504560.10959@infra-view9.cisco.com>
Sender: linux-mips-bounce@linux-mips.org
User-agent: Mutt/1.5.21 (2010-09-15)
On Tue, Nov 08, 2011 at 03:26:42PM -0800, Victor Kamensky wrote:

> > s/insturctions/instructions/
> >
> > Not only is it a bad idea, it will probably make them fail 100% of the time.
> >
> > It is also an equally bad idea to place a probe between any LL and SC
> > instructions.  How do you prevent that?
> 
> As per below code comment we don't prevent that. There is no way to do
> that.

Similar to the way that the addresses of loads and stores from userspace
are recorded in a special section we could build a list of forbidden
address range.

Is it worth it?

  Ralf

<Prev in Thread] Current Thread [Next in Thread>