Re: [PATCH -tip tracing/kprobes 3/6] kprobes/x86: Fix to add __kprobes to in-kernel fault handing functions

[Frederic Weisbecker <fweisbec at gmail dot com>]

On Sat, Aug 29, 2009 at 10:49:47PM -0400, Masami Hiramatsu wrote:
> Frederic Weisbecker wrote:
> > On Thu, Aug 27, 2009 at 01:23:11PM -0400, Masami Hiramatsu wrote:
> >> Add __kprobes to the functions which handles in-kernel fixable page faults.
> >> Since kprobes can cause those in-kernel page faults by accessing kprobe data
> >> structures, probing those fault functions will cause fault-int3-loop
> >> (do_page_fault has already been marked as __kprobes).
> > 
> > 
> > BTW, is it possible to assert a struct kprobe (and its pointer members)
> > haven't been allocated through vmalloc() ?
> > 
> 
> How about calling vmalloc_sync() always before registering kprobes? :-)
> 
> Thank you,


Sounds good :)

BTW, after your patchset:

TEST    posttest
  Building modules, stage 2.
Error: c0101038:	2e a1 f8 b0 9e c0    	mov    %cs:0xc09eb0f8,%eax
Error: objdump says 6 bytes, but insn_get_length() says 10 (attr:40000)
make[1]: *** [posttest] Erreur 2
make: *** [bzImage] Erreur 2
make: *** Attente des tâches non terminées....
  MODPOST 4 modules


I'm cross compiling from 64 to 32 using:

make ARCH=x86

I've attached my config.

Thanks.

Attachment: config-32
Description: Text document