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Re: usb_keyboard not available as a terminal input?

From: Andrei Borzenkov
Subject: Re: usb_keyboard not available as a terminal input?
Date: Mon, 22 May 2017 06:38:14 +0300
User-agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.1.1

21.05.2017 23:02, Tom Yan пишет:
> It seems like the "disappearance" of storage drives after `insmod ehci` is 
> not relevant to whether the drives are USB ones.
> For example, if I start a virtual machine with this:
> qemu-system-x86_64 -enable-kvm -drive file=grub.img -drive 
> if=pflash,readonly,file=ovmf_x64.bin
> And do this after grub started:
> `ls; insmod ehci; ls`
> It will print only _one_ line with multiple storage drives:
> (hd0), (hd0, gpt1), (fd0), (fd1), (cd0)
> which indicates that _everything_ is gone after the insmod command. Same case 
> with ohci/uhci.
> This seems like a bug to me.

it works as designed. USB driver change hardware state, so we cannot
give control back to firmware. You need to use direct hardware access
drivers from this point on. "nativedisk" command handles disk access for

This is still best effort. We hope that firmware won't try to access
hardware on its own, but we do not really know it nor control it.

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