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Misinterpretation of Standard Causing USB Disconnects On Resume In Linux

Posted by samzenpus on from the who's-to-blame dept.

hypnosec writes "According to a new revelation by Sarah Sharp, misinterpretation of the USB 2.0 standard may have been the culprit behind USB disconnects on resume in Linux all along rather than cheap and buggy devices. According to Sharp the USB core is to blame for the disconnections rather than the devices themselves as the core doesn't wait long enough for the devices to transition from a 'resume state to U0.' The USB 2.0 standard states that system software that handles USB must provide for 10ms resume recovery time (TRSMRCY) during which it shouldn't attempt a connection to the device connected to that particular bus segment."

5 of 280 comments (clear)

  1. A bug in Linux? by Anonymous Coward · · Score: 5, Funny

    Clearly the whole thing is broken, and we should transition to a newer, more open and transparent system than even open source.

    I will call it OPENER Source. You aren't just able to read the source, you're required to read it!

  2. Re:Welcome to EE by Ignacio · · Score: 5, Funny

    The 10ms is for the software. The flip side of this is that the hardware has a maximum of 10ms to get its shit together so that it can be connected to. And 10ms is forever in hardware.

    Dear Linux kernel, i'll be ready when my disk is done spinning up. kthanksbye

    Dear USB hard drive, that's fine, but don't go and disconnect from the USB bus in the meantime. Forever waiting, Linux kernel.

  3. Re:not surprising by philip.paradis · · Score: 4, Funny

    THe other one is my wife's so it isn't running Linux.

    My wife's laptop is running Debian 7. What's up with your wife? :)

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    Write failed: Broken pipe
  4. Re:not surprising by Alsee · · Score: 4, Funny

    Oh heavens, it must be happening again. I'm obviously experiencing a relapse of those terrible hallucinations that have plagued me for years.
    Oh, wait, she's real after all.

    Dude, you posted a photo of a laptop sitting on the armrest of an empty couch ;)

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    - - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
  5. Re: not surprising by Muad'Dave · · Score: 4, Funny

    ... stubbornly refuses to sleep with win7. Works fine with Linux.

    At least she has some standards.

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    Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.