Re: [PATCH v3 3/4] x86, mpx: add prctl commands PR_MPX_INIT,PR_MPX_RELEASE

From: Ingo Molnar
Date: Sun Jan 26 2014 - 03:22:10 EST



* Qiaowei Ren <qiaowei.ren@xxxxxxxxx> wrote:

> This patch adds the PR_MPX_INIT and PR_MPX_RELEASE prctl()
> commands on the x86 platform. These commands can be used to
> init and release MPX related resource.
>
> A MMU notifier will be registered during PR_MPX_INIT
> command execution. So the bound tables can be automatically
> deallocated when one memory area is unmapped.
>
> Signed-off-by: Qiaowei Ren <qiaowei.ren@xxxxxxxxx>
> ---
> arch/x86/Kconfig | 4 ++
> arch/x86/include/asm/mpx.h | 9 ++++
> arch/x86/include/asm/processor.h | 16 +++++++
> arch/x86/kernel/mpx.c | 84 ++++++++++++++++++++++++++++++++++++++
> include/uapi/linux/prctl.h | 6 +++
> kernel/sys.c | 12 +++++
> 6 files changed, 131 insertions(+), 0 deletions(-)

Hm. What is the expected typical frequency of these syscalls for a
larger application like a web browser? Only once per startup
typically, or will they be called more frequently?

Thanks,

Ingo
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/