RPCAUTH_CRED_NEGATIVE
if (test_bit(RPCAUTH_CRED_NEGATIVE, &cred->cr_flags)) {
clear_bit(RPCAUTH_CRED_NEGATIVE, &gss_cred->gc_base.cr_flags);
set_bit(RPCAUTH_CRED_NEGATIVE, &gss_cred->gc_base.cr_flags);