[External] : Re: [RFC][PATCH v11 0/7] Implementation of RTLD_SHARED for dlmopen

[Alfonso Alfonso Peterssen]

I'm testing these patches for our use case in GraalVM. We use dlmopen to load several isolated JVMs within the same process.

With the patches I'm hitting the following error:
Inconsistency detected by ld.so: dl-version.c: 205: _dl_check_map_versions: Assert
ion `needed != NULL' failed!

Here's the tail of the LD_DEBUG=all log:
   222389:       trying file=./nptl/tls/x86_64/libpthread.so.0
   222389:       trying file=./nptl/tls/libpthread.so.0
   222389:       trying file=./nptl/x86_64/x86_64/libpthread.so.0
   222389:       trying file=./nptl/x86_64/libpthread.so.0
   222389:       trying file=./nptl/x86_64/libpthread.so.0
   222389:       trying file=./nptl/libpthread.so.0
   222389:
   222389:     checking for version `GLIBC_2.2.5' in file ./dlfcn/libdl.so.2 [0]
required by file /home/mukel/Desktop/graal/graal/sdk/mxbuild/linux-amd64/GRAALVM_E
SPRESSO_JVM_EE_JAVA11/graalvm-espresso-jvm-ee-java11-21.2.0-dev/lib/libnio.so [1]
   222389:     checking for version `GLIBC_2.2.5' in file ./nptl/libpthread.so.0
[0] required by file /home/mukel/Desktop/graal/graal/sdk/mxbuild/linux-amd64/GRAAL
VM_ESPRESSO_JVM_EE_JAVA11/graalvm-espresso-jvm-ee-java11-21.2.0-dev/lib/libnio.so
[1]
   222389:     checking for version `GLIBC_2.3' in file ./libc.so.6 [0] required
by file /home/mukel/Desktop/graal/graal/sdk/mxbuild/linux-amd64/GRAALVM_ESPRESSO_J
VM_EE_JAVA11/graalvm-espresso-jvm-ee-java11-21.2.0-dev/lib/libnio.so [1]
   222389:     checking for version `GLIBC_2.3.2' in file ./libc.so.6 [0] require
d by file /home/mukel/Desktop/graal/graal/sdk/mxbuild/linux-amd64/GRAALVM_ESPRESSO
_JVM_EE_JAVA11/graalvm-espresso-jvm-ee-java11-21.2.0-dev/lib/libnio.so [1]
   222389:     checking for version `GLIBC_2.4' in file ./libc.so.6 [0] required
by file /home/mukel/Desktop/graal/graal/sdk/mxbuild/linux-amd64/GRAALVM_ESPRESSO_J
VM_EE_JAVA11/graalvm-espresso-jvm-ee-java11-21.2.0-dev/lib/libnio.so [1]
   222389:     checking for version `GLIBC_2.2.5' in file ./libc.so.6 [0] require
d by file /home/mukel/Desktop/graal/graal/sdk/mxbuild/linux-amd64/GRAALVM_ESPRESSO
_JVM_EE_JAVA11/graalvm-espresso-jvm-ee-java11-21.2.0-dev/lib/libnio.so [1]
Inconsistency detected by ld.so: dl-version.c: 205: _dl_check_map_versions: Assert
ion `needed != NULL' failed!


We use dlmopen a lot, but never seen this error before, hopefully you can pinpoint the issue. The program in question runs fine without the patches.
I'm running with ./testrun.sh .
I can provide a reproducer, but the setup is quite cumbersome. I can also test any further patches locally if needed.
We've been following this feature for a long time (with great excitement) and just wanted to make sure it works (or that at least doesn't break us) before it's merged.

Best,
Alfonso

________________________________
From: Libc-alpha <libc-alpha-bounces+alfonso.peterssen=oracle.com@sourceware.org> on behalf of Vivek Das Mohapatra via Libc-alpha <libc-alpha@sourceware.org>
Sent: Thursday, June 10, 2021 12:50 AM
To: Florian Weimer <fweimer@redhat.com>
Cc: Vivek Das Mohapatra via Libc-alpha <libc-alpha@sourceware.org>
Subject: [External] : Re: [RFC][PATCH v11 0/7] Implementation of RTLD_SHARED for dlmopen

On Wed, 9 Jun 2021, Florian Weimer wrote:

>>  - libpthread still has the new section applied as I'm not 100% sure it doesn't
>>    still need this treatment. I would like to investigate further before
>
> libpthread does not need this anymore.  We can safely load it as many
> times as we want.

Ok, thanks. I'll update the patch series.