For IOMMU-related part, as mentioned above, the IVRS table does not list the 
correct IOAPIC IDs. This would cause driver to disable interrupt-remapping 
support provided by HW IOMMU.
Here the "ivrs_ioapic[4]=00:14.0 ivrs_ioapic[5]=00:00.2" boot option is needed 
to override the table. Permanent solution would be for laptop OEMs (e.g. Acer, 
Lenovo) to fix this in their BIOSes.

Another alternative would be:
* Disable IOMMU in the BIOS (which should also get rid of the IVRS table)
* Disable HW IOMMU and use SWIOTLB for any DMA-remapping (iommu=soft)

However, I'm not sure about why the "noapic" option is needed.

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https://bugs.launchpad.net/bugs/1776563

Title:
  Acer Aspire A315 IOAPIC failure on Ubuntu 18.04, kernel hangs, can't
  load, kernel freeze  (AMD Ryzen 5/Radeon/Raven) / AMDGPU Hybrid crash

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