Ubuntu
linux package

  1. Cosmic (18.10)
  2. Bug #1747463
  3. Comment #0

Comment 0 for bug 1747463

Revision history for this message
Peridot (peridot) wrote : kernel crashes unless IOMMU is disabled on Ryzen 1800X

I'm on a Ryzen 1800X and Biostar B350GT5 on bionic kubuntu.

Lots of AMD-Vi logged events and I get irq crashes or acpi hangups with a normal boot. How I it to work is to disable IOMMU in the BIOS and add "iommu=soft" to the kernel booting options in grub.

linux can then detect everything properly (all cores) and I've had zero crashes. The only issue is that it's using software IOMMU.

Alternatively it boots with the kernel option "acpi=off" but only detects a single core/thread.

I attached a kernel log.

I believe(d) this might be related to https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1671360
and https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1690085