Hi Fenghua, I was testing some new MPX code, and realized that MPX had stopped working completely. The prctl() failed to turn it on, which I tracked down to a 0 in "BNDCSR" where we expected to see an enable bit.
I realized that I had managed to remove the "noxsaves" boot option from my kernel. Re-adding "noxsaves" made MPX work again, and the BNDCSR contents were properly passed in to the kernel. Is it possible that "xsaves" use inside the kernel is simply broken? Config is here: http://sr71.net/~dave/intel/config-20150302 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/