Re: "Enhanced" MD code avaible for review

From: Jeff Garzik (jgarzik_at_pobox.com)
Date: 03/26/04

  • Next message: Andrew Morton: "Re: [PATCH 4/22] /dev/random: remove outdated RNDGETPOOL ioctl" 
    Date:	Thu, 25 Mar 2004 19:13:36 -0500
To: "Justin T. Gibbs" <gibbs@scsiguy.com>

    Justin T. Gibbs wrote:
    >>I respectfully disagree with the EMD folks that a userland approach is
    >>impossible, given all the failure scenarios.
    >
    >
    > I've never said that it was impossible, just unwise. I believe
    > that a userland approach offers no benefit over allowing the kernel
    > to perform all meta-data operations. The end result of such an
    > approach (given feature and robustness parity with the EMD solution)
    > is a larger resident side, code duplication, and more complicated
    > configuration/management interfaces.

    There is some code duplication, yes. But the right userspace solution
    does not have a larger RSS, and has _less_ complicated management
    interfaces. A key benefit of "do it in userland" is a clear gain in
    flexibility, simplicity, and debuggability (if that's a word).

    But it's hard. It requires some deep thinking. It's a whole lot easier
    to do everything in the kernel -- but that doesn't offer you the
    protections of userland, particularly separate address spaces from the
    kernel, and having to try harder to crash the kernel. :)

            Jeff

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  • Next message: Andrew Morton: "Re: [PATCH 4/22] /dev/random: remove outdated RNDGETPOOL ioctl"

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