Re: [mp2] mod_perl 2.0.7 Segfault When Loading Certain Perl Module

Tue, 14 Aug 2012 14:58:03 -0700 

Hello Fred,
Thank you for pointing out the upcoming release. Unfortunately, after checking out and installing the latest version from SVN, I'm still seeing the same issue. Apache still segfault while trying to load any Perl module that directly or indirectly use Carp. According to "SVN info -r HEAD", the reversion I'm using is 1373130. 


One thing I noticed from strace is that the module seems to be loaded 
successfully the first time ( according to mod_perl2 doc, Apache 2 will 
perform a restart right after initial start. so every module will be 
loaded twice... ), and only when it is to be loaded the second time the 
segfault occurs. Perhaps there are some differences between the first 
and second module load during apache/mod_perl initialization that's 
causing the segfault?



Best,
Jason

On 08/14/2012 12:17 PM, Fred Moyer wrote:

Can you try the latest version from source?

http://perl.apache.org/download/source.html

It looks like you are using perl 5.16, some recent fixes were
committed there. The subversion tip will likely be the 2.0.8 RC in a
week or so.

On Mon, Aug 13, 2012 at 3:01 PM, Jason Lin <jason...@ucar.edu> wrote:

Hi,

I work for a project that has been using mod_perl for quite a while.
Recently, we upgraded our 64-bit web server with Perl 5.16, mod_perl 2.0.7
(it's 2.0.6 with patch), and apache 2.2.22 on CentOS 6.3. Since then, we've
been unable to start Apache server (segmentation faults) with same
httpd.conf which worked previously.

As far as I can tell, the segfault seems to be triggered while trying to
load any Perl module using either PerlModule directive or in <Perl> block in
httpd.conf that directly or indirectly use Carp, or even just try to load
Carp itself. Strace shows that the process would segfault while loading (or
right after loading) Carp.pm. The server can still successfully start and
work when carefully removing such modules in httpd.conf.

Is anyone seeing this same issue or have any ideas how it can be fixed other
than trying to hack through all the Perl modules to make sure Carp is not
called?


perl -V
Summary of my perl5 (revision 5 version 16 subversion 0) configuration:

   Platform:
     osname=linux, osvers=2.6.32-279.1.1.el6.x86_64, archname=x86_64-linux
     uname='linux fox.cosmic.ucar.edu 2.6.32-279.1.1.el6.x86_64 #1 smp tue
jul 10 13:47:21 utc 2012 x86_64 x86_64 x86_64 gnulinux '
     config_args='-Dprefix=/ops/tools -des
-Accflags=-DPERL_RELOCATABLE_INCPUSH'
     hint=recommended, useposix=true, d_sigaction=define
     useithreads=undef, usemultiplicity=undef
     useperlio=define, d_sfio=undef, uselargefiles=define, usesocks=undef
     use64bitint=define, use64bitall=define, uselongdouble=undef
     usemymalloc=n, bincompat5005=undef
   Compiler:
     cc='cc', ccflags ='-DPERL_RELOCATABLE_INCPUSH -fno-strict-aliasing -pipe
-fstack-protector -I/usr/local/include -D_LARGEFILE_SOURCE
-D_FILE_OFFSET_BITS=64',
     optimize='-O2',
     cppflags='-DPERL_RELOCATABLE_INCPUSH -fno-strict-aliasing -pipe
-fstack-protector -I/usr/local/include'
     ccversion='', gccversion='4.4.6 20120305 (Red Hat 4.4.6-4)',
gccosandvers=''
     intsize=4, longsize=8, ptrsize=8, doublesize=8, byteorder=12345678
     d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=16
     ivtype='long', ivsize=8, nvtype='double', nvsize=8, Off_t='off_t',
lseeksize=8
     alignbytes=8, prototype=define
   Linker and Libraries:
     ld='cc', ldflags =' -fstack-protector -L/usr/local/lib'
     libpth=/usr/local/lib /lib/../lib64 /usr/lib/../lib64 /lib /usr/lib
/lib64 /usr/lib64 /usr/local/lib64
     libs=-lnsl -lgdbm -ldl -lm -lcrypt -lutil -lc
     perllibs=-lnsl -ldl -lm -lcrypt -lutil -lc
     libc=, so=so, useshrplib=false, libperl=libperl.a
     gnulibc_version='2.12'
   Dynamic Linking:
     dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags='-Wl,-E'
     cccdlflags='-fPIC', lddlflags='-shared -O2 -L/usr/local/lib
-fstack-protector'


Characteristics of this binary (from libperl):
   Compile-time options: HAS_TIMES PERLIO_LAYERS PERL_DONT_CREATE_GVSV
                         PERL_MALLOC_WRAP PERL_PRESERVE_IVUV
                         PERL_RELOCATABLE_INCPUSH USE_64_BIT_ALL
                         USE_64_BIT_INT USE_LARGE_FILES USE_LOCALE
                         USE_LOCALE_COLLATE USE_LOCALE_CTYPE
                         USE_LOCALE_NUMERIC USE_PERLIO USE_PERL_ATOF
   Built under linux
   Compiled at Aug  1 2012 16:14:39
   %ENV:
     PERL5LIB="/ops/tools/lib"
   @INC:
     /ops/tools/lib
     /ops/tools/lib/perl5/site_perl/5.16.0/x86_64-linux
     /ops/tools/lib/perl5/site_perl/5.16.0
     /ops/tools/lib/perl5/5.16.0/x86_64-linux
     /ops/tools/lib/perl5/5.16.0
     .

Note that we compiled Perl with relocation flag (-DPERL_RELOCATABLE_INCPUSH)
turned on, yet same issue can also be found without the flag in our test.

Any help/advice would be appreciated, thank you in advance.


Best,
Jason
























					Reply via email to