From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tobias Geiger Subject: Regression since 4.1 Date: Wed, 09 Dec 2015 18:01:52 +0100 Message-ID: <5418503.92eb9JWhCR@t400> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org List-Id: iommu@lists.linux-foundation.org Hello! in short: No Kernel since 4.1 boots on my machine. I can make newer kernels boot, but ONLY when i remove "iommu=on intel_iommu=on" from the cmdline. If i leave it in, as with all the kernels before and including 4.1, newer kernels dont boot, and in a really not very informative way: They dont even print a single message to the console, i only see the grub- messages (like "loading kernel" and "loading initial ramdisk") - after these messages NO more output of any kind - also no SysRQ keys working - nothing. Because of this complete lack of information, i guess its hard to debug for you the cause of this. Perhaps i can help - but how? i'm writing from a pure IOMMU-User perspective - i can compile kernels, but never git-bisected, so maybe a hint to a tutorial for that would be great! Greetings and thanks for your insight! Tobias