On Fri, Oct 14, 2022 at 04:02:02PM +0200, Olivier Matz wrote: > Hi Robin, > > On Thu, Oct 13, 2022 at 03:41:25PM +0200, Robin Jarry wrote: > > Some environments (buildroot) do not have the ldd utility installed by > > default. However, ldd is often only a wrapper shell script that actually > > checks that the arguments are valid ELF files and executes them with > > the LD_TRACE_LOADED_OBJECTS=1 variable set in the environment. > > > > Since ld.so is the actual ELF interpreter which is loaded first when > > executing a program, executing any dynamic ELF program/library with that > > variable set will cause all dependent dynamic libraries to be printed > > and ld.so will exit before even running main. > > > > Excerpt from ld.so(7) man page: > > > > LD_TRACE_LOADED_OBJECTS > > If set (to any value), causes the program to list its dynamic > > dependencies, as if run by ldd(1), instead of running normally. > > > > Change dpdk-pmdinfo.py to actually "execute" the files provided on the > > command line with LD_TRACE_LOADED_OBJECTS=1 set. Ensure that the files > > are valid dynamically executable ELF programs to avoid obscure and > > confusing errors. > > > > Reported-by: Olivier Matz <olivier.m...@6wind.com> > > Signed-off-by: Robin Jarry <rja...@redhat.com> > > Tested on buildroot without ldd. > > Reviewed-by: Olivier Matz <olivier.m...@6wind.com>
After some more tests, it appears that it only works for an executable binary, but it does not work for .so PMDs: # LD_TRACE_LOADED_OBJECTS=1 /usr/lib/x86_64-linux-gnu/dpdk/pmds-22.0/librte_net_ixgbe.so Segmentation fault (core dumped) So it is maybe better to keep the original code using ldd. Thank you Robin anyway.
