> On Sat, Aug 21, 2021 at 7:42 AM Bjørn Mork <bj...@mork.no> wrote: > >> try booting with intel_iommu=off on the kernel command line > > It works now, thanks for your help.
Great! Glad it could be resolved as easily as that. > Is there a known bug or something? Probably a firmware bug. I don't know. Such issues are pretty common, and disabling the IOMMU is the first thing you should try. Sometimes it just doesn't play well with some other feature. If you don't need it then you might as well just disable it. My Thinkpad fails to suspend if I enable both IOMMU and TPM 2.0. One of them is OK, but not both. Go figure. This is https://bugs.debian.org/949020 For some background: https://www.kernel.org/doc/html/latest/x86/intel-iommu.html There are also a number of other options than "off" you could try if you want to play with it: https://www.kernel.org/doc/html/v4.14/admin-guide/kernel-parameters.html Note that the bug has probably always been there in your PC firmware. It showed up now because Debian changed the default from "off" to "on". Bjørn
