2013/6/12 Alexander E. Patrakov <patrakov@xxxxxxxxx>: > 2013/6/12 Jiang Liu <liuj97@xxxxxxxxx>: >> On Wed 12 Jun 2013 12:51:59 AM CST, Alexander E. Patrakov wrote: >>> In the initially-docked case, it exhibits the following problem: when >>> I press the undock button, only one PCI device disappears, and the >>> "docked" LED does not turn off. Additionally, there is a hung task. >> Hi Alexander, >> In the initially-docked case, the failure is caused by an issue in >> the intel sound card driver. Seems something is wrong with reference >> count management and it never returns to zero on driver detach. >> Could you please help to disable the Intel sound card driver and try >> again? >> >> I'm not familiar with Intel HDA driver, so please help to fire another >> bug for it. > > Thanks for pointing the finger to snd-hda-intel. With that driver > blacklisted, the lspci output matches the expectations even after > undocking the initially-docked laptop. Redocking re-adds the devices, > too. > As for snd-hda-intel bug, I will file it later today and let you know. Actually, I debugged it further and want some input from you before filing. Here is the new information: the incomplete undocking and hung task does not appear if I test from a virtual console, not from an XFCE session. The obvious difference is that in the XFCE session some processes (the mixer applet and pulseaudio) keep the mixer device always open. I am not qualified enough to say what should happen if the user presses the undock button while a program has a to-be-undocked device open. Or, for that matter and for an analogy, if the user unplugs a USB sound card while it is playing. And in my case, this is going to be an issue not only because of the snd-hda-intel driver. Xorg would sometimes keep the DRM node of the Radeon card (that is in the dock station) open in addition to the onboard Intel card. -- Alexander E. Patrakov -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
