- fix pfm_free_fd() to clear current->files->fd[fd] in
    case of error during PFM_CONTEXT_CREATE, i.e., undo
    the effect of fd_install(). This could cause kernel
    panic if the file descriptor gets used by error through
    perfmon.
  - fix pfm_context_create() to correctly propagate the
    return value of pfm_alloc_fd().
signed-off-by: stephane eranian <eranian@hpl.hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>