lkml.org 
[lkml]   [1997]   [Feb]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: Unable to handle kernel paging request
On Mon, 24 Feb 1997, Jon Lewis wrote:

> On Mon, 24 Feb 1997, Bernd Schmidt wrote:
>
> > I'd like to agree, but I've seen another bug report like this, and I noticed
> > that in both cases, the function elf_core_dump appeared in the stack trace.
> > I even still have the original mail. The author (Johnny Stenback) claims the
> > problem is reproducible with the following test program:
>
> I've run Bernd's program several times now and am fairly convinced this is
> a kernel problem...not bad RAM. I got almost identical ksymoops data from
> both the user's mud and Bernd's program. I've upgraded to 2.0.29, and
> still get very similar results from Bernd's program. First run segfaults,
> additional runs go to state D and none can be killed...so I had to reboot
> again.

Very weird.. I ran it, too, and it simply segfaults, no oops, no state D,
no problem whatsoever.

There are two possibilities here:
1. file "test" doesn't exist, so mmap returns -1 (??? it should return
NULL), the first attempt to dereference the pointer segfaults, end of
story.
2. file "test" does exist, mmap returns a valid pointer, the first attempt
to read from that memory region segfaults because of PROT_WRITE protection
(no reading allowed). End of story.

Kernel 2.0.29 with minimal modifications, libc 5.4.23.

Any other takers?


Ionut

--
It is better to keep your mouth shut and be thought a fool,
than to open it and remove all doubt.


\
 
 \ /
  Last update: 2005-03-22 13:39    [from the cache]
©2003-2011 Jasper Spaans