RE: [Qemu-devel] USB storage cannot be recognized on guest Linuxdomain?
Lonnie, Thank you so much for write the patch for me! It works well with Fedora Core 4. Since it added UHCI suspend/resume support, so I guess it should also work with Windows XP :-) Thanks Xiaoyang -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Lonnie Mendez Sent: 2007年2月15日 22:49 To: qemu-devel@nongnu.org Subject: RE: [Qemu-devel] USB storage cannot be recognized on guest Linuxdomain? On Thu, 2007-02-15 at 15:44 +0800, Yu, Xiaoyang wrote: > Hi Lonnie, > > Thanks a lot for the information. > > In our use case, we do not know the USB disk information before it is plugged > by customer, so we cannot start qemu with -usbdevice. > > For Linux, reload the uhci_hcd driver works. If we use this solution in our > use case, then we need to issue an interrupt (maybe by pic_set_irq_new?) to > the guest OS when QEMU detect a USB device is attached, and then the guest OS > will reload the uhci_hcd driver. Is that right? Currently there is something > wrong with the list archive server, so I haven't search out any example code > from it :-( > > I found that there is a patch to add the UHCI suspend/resume support in the > archive posted by you, but it cannot be applied to QEMU-DM 0.8.2 directly: > http://lists.gnu.org/archive/html/qemu-devel/2006-04/msg00576.html > > I wonder why there is no official UHCI suspend/resume support in QEMU. To > reload the uhci_hcd driver seems to be only a work around. Sometimes it even > cause kernel oops. > > I also wonder why the kernel 2.6.11-1.1369_FC4 can recognize USB storage > without UHCI suspend/resume support. The attached patch is enough to have a device on linux recognized after usb_add. However, the device must be attached to the uhci controller's root hub. If a device is attached to an emulated usb hub device it will not be detected. ___ Qemu-devel mailing list Qemu-devel@nongnu.org http://lists.nongnu.org/mailman/listinfo/qemu-devel
RE: [Qemu-devel] USB storage cannot be recognized on guest Linuxdomain?
On Thu, 2007-02-15 at 10:36 +0800, Yu, Xiaoyang wrote: > Thanks a lot for the instruction. Will the suspend/resume support be added in > the future release? > > Without the suspend/resume support, is there anything can be done in the > guest domain to help detect a USB device? Maybe patch the kernel? For windows you can disable the power management for the controller. That will cause windows to constantly poll hub status. For linux you have to reload the uhci hcd driver. Notice that starting qemu with -usbdevice works. The code to implement this is very easy. You basically set/clear some bits and trigger an interrupt. See list archives for example code. ___ Qemu-devel mailing list Qemu-devel@nongnu.org http://lists.nongnu.org/mailman/listinfo/qemu-devel
RE: [Qemu-devel] USB storage cannot be recognized on guest Linuxdomain?
Thanks a lot for the instruction. Will the suspend/resume support be added in the future release? Without the suspend/resume support, is there anything can be done in the guest domain to help detect a USB device? Maybe patch the kernel? Thanks Xiaoyang -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Lonnie Mendez Sent: 2007年2月14日 23:01 To: qemu-devel@nongnu.org Subject: RE: [Qemu-devel] USB storage cannot be recognized on guest Linuxdomain? On Wed, 2007-02-14 at 18:26 +0800, Yu, Xiaoyang wrote: > BTW, I also found that Windows XP guest domain can not recognize the > USB disk, while Windows XP SP2 guest domain can recognize the USB > disk. So it seems like that the guest Linux/Windows domain should have > some “special feature” to work with the QEMU USB emulation > successfully. Isn’t it strange? The uhci emulation has no suspend/resume support. From your description this is exactly the problem you are seeing. ___ Qemu-devel mailing list Qemu-devel@nongnu.org http://lists.nongnu.org/mailman/listinfo/qemu-devel
