02-06-2012 01:41 AM - edited 02-06-2012 01:42 AM
on booting the abovmentioned configuration, at boot time, everything stops with multiple "udev..." messages.
If I disable VT, boot process completes.
I have tried a different Linux flavour (Gentoo 64-bit) and the same thing happens with VT enabled.
Anyone any ideas??
PS Debian Kernel is 3.2.
02-06-2012 07:18 AM
Is there anything useful in the thread below? I haven't chased down all the links, but it looks similar.
The large print: please read the Community Participation Rules before posting. Include as much information as possible: model, machine type, operating system, and a descriptive subject line. Do not include personal information: serial number, telephone number, email address, etc.
The fine print: I do not work for, nor do I speak for Lenovo. Unsolicited private messages will be ignored - questions and answers belong in the forum so that others may benefit. ... GeezBlog
02-08-2012 11:02 PM - edited 02-08-2012 11:05 PM
I'm running Fedora 16 64-bit on my W520 with VT-d enabled. The difference is that I disabled the NVidia card in the bios and use the Intel graphics. Better battery life, too.
This bug with the NVidia driver/chip has been out for a while now. It would be nice if somebody at NVidia would fix it, or give us the source so we can fix it ourselves...
Edit: seems like its fixed in NVidia driver 295.09 beta (beta is a state of mind!)
02-24-2012 08:19 AM
I see that BIOS 1.36 has been released for the abovementioned Thinkpad.
I have duly installed same but STILL CANNOT boot my Debian 64-bit Linux with VT-D enabled.
Thousands of "DRAM..error" and / or UDEV messages are issued at the start of the boot sequence.
I do not want to run this machine with ACPI=off and only run with one CPU or try any hacks to try and circumvent this nor am I interested in running on the integrated Intel GPU (which also does not work, see above error message description).
I am currently running with the Nvidia 295.09 driver.
A DEFINITIVE STATEMENT from Lenovo on whether this is a BIOS problem or not would be helpful.
02-26-2012 09:18 AM
Please understand that the Linux boards in this forum are going to have to run as peer to peer support. Lenovo supports the Windows preloads, so while it is possible we have some quirk that needs to be addressed in BIOS it is difficult to open this as a formal problem for engineering to chase to a definitive solution.
If this ALSO occurs under windows, then it may be easier to obtain greater focus on the issue.
That said, if you will post some additional details on this including the error list. (Is there a way you can capture the list?)
We can try check into this a bit further.
I appreciate your understanding.
02-26-2012 10:33 AM
as these messages (see previous posts) happen at the very start of the boot sequence, it is impossible for the kernel to start writing its logs, hence the difficulty in providing "hard" evidence.
Supposedly there was a Linux kernel (IOMMU) bug in the early 3.x kernels that should have been addressed in the latest (3.3) kernel, alas, this is not the case - still the same problem. See this post - http://www.phoronix.com/scan.php?page=news_item&px=MTAzNzk
The problem also occurs when I use the Intel integrated graphics card only (i.e. disable the Nvidia card).
I have tried this (enable VT-d) with Liquorix kernels 3.0-3.2 and a vanilla 3.3 kernel, all with the same result.
Here is one of many google hits returned if one enters the following keywords "w520 bios vt-d dmar boot"
02-27-2012 07:30 AM
below URL for W520 DMESG boot with VT-d disabled.
[URL=http://www.zshare.net/download/99166017a138c52e/]W520-Boot-VT-d_disabled.txt - 0.04MB[/URL]