On 06/23/2014 01:00 PM, Andy Lutomirski wrote: > On 06/18/2014 02:44 AM, Qiaowei Ren wrote: >> > This patch adds the PR_MPX_REGISTER and PR_MPX_UNREGISTER prctl() >> > commands. These commands can be used to register and unregister MPX >> > related resource on the x86 platform. >> > >> > The base of the bounds directory is set into mm_struct during >> > PR_MPX_REGISTER command execution. This member can be used to >> > check whether one application is mpx enabled. > The register and unregister operations seem to be almost the same thing. > How about just PR_SYNC_MPX?
That wouldn't support a usage model where userspace wanted to keep using MPX, but wanted the kernel to butt out and not try to free unused bounds tables. That's not super-important, but it does lose some level of flexibility. FWIW, I think it would also be handy to support a PR_MPX_DISABLE prctl too. That way, a wrapper program could set a flag that any children could notice if they try a PR_MPX_REGISTER. That way we could software-disable MPX in cases in a process tree where it was not wanted. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
