• Adrian Hunter's avatar
    perf test: Enable Symbols test to work with a current module dso · 6f04d664
    Adrian Hunter authored
    The test needs a struct machine and creates one for the current host,
    but a side-effect is that struct machine has set up kernel maps
    including module maps.
    
    If the 'Symbols' test --dso option specifies a current kernel module,
    it will already be present as a kernel dso, and a map with kmaps needs
    to be used otherwise there will be a segfault - see below.
    
    For that case, find the existing map and use that. In that case also,
    the dso is split by section into multiple dsos, so test those dsos
    also. That in turn, shows up that those dsos have not had overlapping
    symbols removed, so the test fails.
    
    Example:
    
      Before:
    
        $ perf test -F -v Symbols --dso /lib/modules/$(uname -r)/kernel/arch/x86/kvm/kvm-intel.ko
         70: Symbols                                                         :
        --- start ---
        Testing /lib/modules/6.7.2-local/kernel/arch/x86/kvm/kvm-intel.ko
        Segmentation fault (core dumped)
    
      After:
    
        $ perf test -F -v Symbols --dso /lib/modules/$(uname -r)/kernel/arch/x86/kvm/kvm-intel.ko
         70: Symbols                                                         :
        --- start ---
        Testing /lib/modules/6.7.2-local/kernel/arch/x86/kvm/kvm-intel.ko
        Overlapping symbols:
         41d30-41fbb l vmx_init
         41d30-41fbb g init_module
        ---- end ----
        Symbols: FAILED!
    Signed-off-by: default avatarAdrian Hunter <adrian.hunter@intel.com>
    Reviewed-by: default avatarIan Rogers <irogers@google.com>
    Signed-off-by: default avatarNamhyung Kim <namhyung@kernel.org>
    Link: https://lore.kernel.org/r/20240131192416.16387-1-adrian.hunter@intel.com
    6f04d664
symbols.c 4.46 KB