On Fri, 26 Jun 2020 15:59:57 +0100 Bruce Richardson <bruce.richard...@intel.com> wrote:
> When using statically linked DPDK binaries, the EAL checks the default PMD > path and tries to load any drivers there, despite the fact that all drivers > are normally linked into the binary. This behaviour can cause issues if > the PMD path and lib dir is configured to a non-standard location which is > not in the ld.so.conf paths, e.g. a build with prefix set to a home > directory location. In a case such as this, EAL will try and > (unnecessarily) load the .so driver files but that load will fail as their > dependent libraries, such as ethdev, for example, will not be found. > > Because of this, it is better if statically linked DPDK apps do not load > drivers from the standard paths automatically. The user can always have > this behaviour by explicitly specifying the path using -d flag, if so > desired. > > Not loading the libraries automatically can also prevent potential issues > with a user building and running a statically-linked DPDK binary based off > a private copy of DPDK, while there exists on the same machine a > system-wide installation of DPDK in the default locations. Without this > change, the system-installed drivers will be loaded to the binary alongside > the statically-linked drivers, which is not what the user would have > intended. > > To detect whether we are in a statically or dynamically linked binary, we > can have EAL try to get a dlopen handle to its own shared library, by > calling dlopen with the RTLD_NOLOAD flag. This will return NULL if there is > no such shared lib loaded i.e. the code is executing from a static library, > or a handle to the lib if it is loaded. > > Signed-off-by: Bruce Richardson <bruce.richard...@intel.com> But what if the majority of the DPDK is statically linked but the application wants also load a dynamically linked driver?
