Subject: ps command segfault
From: Petar Hitij <petahi@gmail.com>
Date: Mon, 31 Jan 2011 18:38:56 +0100

Hello everybody,

I have the following problem:

1. host system: Debian squeeze
    uname -na
    Linux vitez0 2.6.32-5-vserver-amd64 #1 SMP Wed Jan 12 05:05:13 UTC
2011 x86_64 GNU/Linux


2. guest system was rsync-ed from old server, it contains RedHat 9
32bit instance

3. guest starts ok (mysql, apache, postfix...), ps command (and top)
segfaults when
    it looks into /proc/meminfo.

I have tried to limit memory - cflags VIRTMEM - rlimits/rss 200000,
it didn't help. I cannot list processes in a vserver.

Best regards
Petar Hitij


guest
============

open("/proc/meminfo", O_RDONLY)         = 5
lseek(5, 0, SEEK_SET)                   = 0
read(5, "MemTotal:         800000 kB\nMemF"..., 1023) = 1023
--- SIGSEGV (Segmentation fault) @ 0 (0) ---
+++ killed by SIGSEGV +++
[root@nfp-si /]#
[root@nfp-si /]# cat /etc/redhat-release
Red Hat Linux release 9 (Shrike)
[root@nfp-si /]# ls
bin  boot  dev  etc  home  initrd  lib  lost+found  misc  mnt  opt
poweroff  proc  root  sbin  suitespot  tmp  usr  var
[root@nfp-si /]# cd /proc

[root@nfp-si proc]# df
Filesystem           1K-blocks      Used Available Use% Mounted on
/dev/hdv1             58831036  44385408  11457188  80% /

[root@nfp-si proc]# mount
/dev/hdv1 on / type ufs (defaults)
none on /proc type proc (defaults)
none on /dev/pts type devpts (gid=5,mode=620)

[root@nfp-si proc]# cat /proc/meminfo
MemTotal:         800000 kB
MemFree:          156044 kB
Buffers:          451044 kB
Cached:                0 kB
SwapCached:            0 kB
Active:          1062608 kB
Inactive:       14134812 kB
Active(anon):     199536 kB
Inactive(anon):     9772 kB
Active(file):     863072 kB
Inactive(file): 14125040 kB
Unevictable:           0 kB
Mlocked:               0 kB
SwapTotal:             0 kB
SwapFree:              0 kB
Dirty:                 4 kB
Writeback:             0 kB
AnonPages:        208188 kB
Mapped:            19864 kB
Shmem:              1200 kB
Slab:             666744 kB
SReclaimable:     637332 kB
SUnreclaim:        29412 kB
KernelStack:        2896 kB
PageTables:         4652 kB
NFS_Unstable:          0 kB
Bounce:                0 kB
WritebackTmp:          0 kB
CommitLimit:    13111820 kB
Committed_AS:     798836 kB
VmallocTotal:   34359738367 kB
VmallocUsed:      111536 kB
VmallocChunk:   34350727048 kB
HardwareCorrupted:     0 kB
HugePages_Total:       0
HugePages_Free:        0
HugePages_Rsvd:        0
HugePages_Surp:        0
Hugepagesize:       2048 kB
DirectMap4k:        6384 kB
DirectMap2M:     2080768 kB
DirectMap1G:    14680064 kB


Host
===============

vitez0:~# vserver-info
Versions:
                   Kernel: 2.6.32-5-vserver-amd64
                   VS-API: 0x00020305
             util-vserver: 0.30.215; Jun 18 2010, 13:35:17

Features:
                       CC: gcc, gcc (Debian 4.4.4-5) 4.4.4
                      CXX: g++, g++ (Debian 4.4.4-5) 4.4.4
                 CPPFLAGS: ''
                   CFLAGS: '-Wall -g  -O2 -std=c99 -Wall -pedantic -W
-funit-at-a-time'
                 CXXFLAGS: '-g -O2 -ansi -Wall -pedantic -W
-fmessage-length=0 -funit-at-a-time'
               build/host: x86_64-pc-linux-gnu/x86_64-pc-linux-gnu
             Use dietlibc: yes
       Build C++ programs: yes
       Build C99 programs: yes
           Available APIs: v13,net,v21,v22,v23,netv2
            ext2fs Source: e2fsprogs
    syscall(2) invocation: alternative
      vserver(2) syscall#: 236/glibc
               crypto api: nss
          python bindings: no
   use library versioning: yes

Paths:
                   prefix: /usr
        sysconf-Directory: /etc
            cfg-Directory: /etc/vservers
         initrd-Directory: $(sysconfdir)/init.d
       pkgstate-Directory: /var/run/vservers
          vserver-Rootdir: /var/lib/vservers


Assumed 'SYSINFO' as no other option given; try '--help' for more information.