From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tobias Geiger Subject: Re: Regression since 4.1 Date: Thu, 10 Dec 2015 00:07:57 +0100 Message-ID: <6847091.8HQyRDvvTU@pc> References: <5418503.92eb9JWhCR@t400> <1449688068.15753.461.camel@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1449688068.15753.461.camel-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> 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: Alex Williamson Cc: iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org List-Id: iommu@lists.linux-foundation.org Hello Alex, thanks for looking into this. Nothing helps - not adding "ignore_loglevel" , not removing everything but the most necessary (="BOOT_IMAGE=/boot/vmlinuz-4.3.0-trunk-amd64 ro root=LABEL=dom0root panic=15 iommu=on intel_iommu=on ignore_loglevel") - grub loads the kernel, loads initrd, execs the kernel - and then nothing. no output of any kind from the kernel. no sysrq, no panic-reboot despite panic=15 ... nothing. not even a blinking cursor, just a steady cursor which is still from grub i guess... It all comes down to kernel > 4.1 && iommu=on = not working here Hardware is: Intel DX58SO, Intel CPU i7 920... all pretty solid running for years now, always with iommo=on. I'd love to debug this further, just dont know how... Greetings! Tobias Am Mittwoch, 9. Dezember 2015, 12:07:48 schrieb Alex Williamson: > Try simply removing the "quiet" and "splash" or "rhgb" options if there > are any from the kernel command line in grub first. You can temporarily > just editing the commandline manually as you boot. If you don't have a > serial console available, at least have a camera handy to take a picture > of the screen. You can also add "ignore_loglevel" to the kernel > commandline to get more logging. Thanks, > > Alex