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Description of problem:
With RHEL AS-3 (Taroon-beta2), I get frequent segmentation fault
if stack size is smaller than 2Mbytes.

For example, in tcsh:

perf-lx3:~> limit stacksize 512k
perf-lx3:~> ls
Segmentation fault
perf-lx3:~> cat /proc/self/stat
Segmentation fault

512k stack should be big enough to run simple applications like
ls and cat.

Version-Release number of selected component (if applicable):

perf-lx3:~> uname -a
Linux perf-lx3 2.4.21-1.1931.2.399.entsmp #1 SMP Wed Aug 20 15:51:09 EDT 2003
i686 i686 i386 GNU/Linux

How reproducible:
Always

Steps to Reproduce:
1. limit stacksize 512k
2. cat /proc/self/stat
3.
    

Actual Results:  Segmentation fault

Expected Results:  no crash, contents of /proc/self/stat is printed out

Additional info:

When I set stack limit to larger value, it becomes clear that the 
start_stack field in /proc/self/stat is way off the actual stack 
top (0xC0000000) as shown in /proc/self/maps:

perf-lx3:~> limit stacksize 8192k
perf-lx3:~> cat /proc/self/maps
00e58000-00e6e000 r-xp 00000000 08:03 556071     /lib/ld-2.3.2.so
00e6e000-00e6f000 rw-p 00015000 08:03 556071     /lib/ld-2.3.2.so
00e97000-00fc5000 r-xp 00000000 08:03 147256     /lib/tls/libc-2.3.2.so
00fc5000-00fc9000 rw-p 0012d000 08:03 147256     /lib/tls/libc-2.3.2.so
00fc9000-00fcb000 rw-p 00000000 00:00 0
08048000-0804c000 r-xp 00000000 08:03 196534     /bin/cat
0804c000-0804d000 rw-p 00003000 08:03 196534     /bin/cat
0897a000-0899b000 rw-p 00000000 00:00 0
b75f1000-b77f1000 r--p 00000000 08:03 556073     /usr/lib/locale/locale-archive
b77f1000-b77f2000 rw-p 00000000 00:00 0
bff68000-c0000000 rw-p fffe8000 00:00 0

perf-lx3:~> cat /proc/self/stat
10752 (cat) R 9267 10752 9267 34816 10752 4194304 28 0 105 0 0 0 0 0 16 0 0 0
33764547 4554752 106 4294967295 134512640 134525428 3220289040 3220288580 9721294
0 0 0 0 0 0 0 17 0 0 0 0 0 0 0
perf-lx3:~> cat /proc/self/stat
10753 (cat) R 9267 10753 9267 34816 10753 4194304 28 0 105 0 0 0 0 0 16 0 0 0
33764669 4907008 106 4294967295 134512640 134525428 3219937664 3219937204 5240270
0 0 0 0 0 0 0 17 0 0 0 0 0 0 0
perf-lx3:~> cat /proc/self/stat
10754 (cat) R 9267 10754 9267 34816 10754 4194304 28 0 105 0 0 0 0 0 16 0 0 0
33764734 4050944 106 4294967295 134512640 134525428  3220791060 5502414
0 0 0 0 0 0 0 17 0 0 0 0 0 0 0

Notice that the start_stack value is different in each run 
(3220289040, 3219937664, 3220791520). It is about 400K to
1.2M below the actual stack top (0xC0000000). This seems wrong.