Bug 201123

Standard kernel (I was using Archlinux's 4.18.6, I've tried 4.18.7 in testing too) does not boot on my machine with error saying that

	Kernel panic - not syncing: timer doesn't work through Interrupt-remapped IO-APIC

Screenshot of the whole error (sorry, phone photo of the screen, didn't figure out how to save the error in text form) attached.

By adding `amd_iommu=off` to the kernel command line I'm able to boot the system (there are other issues but probably unrelated). I'm also using `ivrs_ioapic[32]=00:00.2` to get rid of the "Firmware Bug" line.

My system is fairly new hardware, here's lspci

	   $ lspci
	00:00.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 15d0
	00:00.2 IOMMU: Advanced Micro Devices, Inc. [AMD] Device 15d1
	00:01.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) PCIe Dummy Host Bridge
	00:01.2 PCI bridge: Advanced Micro Devices, Inc. [AMD] Device 15d3
	00:01.3 PCI bridge: Advanced Micro Devices, Inc. [AMD] Device 15d3
	00:01.4 PCI bridge: Advanced Micro Devices, Inc. [AMD] Device 15d3
	00:01.6 PCI bridge: Advanced Micro Devices, Inc. [AMD] Device 15d3
	00:08.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) PCIe Dummy Host Bridge
	00:08.1 PCI bridge: Advanced Micro Devices, Inc. [AMD] Device 15db
	00:08.2 PCI bridge: Advanced Micro Devices, Inc. [AMD] Device 15dc
	00:14.0 SMBus: Advanced Micro Devices, Inc. [AMD] FCH SMBus Controller (rev 61)
	00:14.3 ISA bridge: Advanced Micro Devices, Inc. [AMD] FCH LPC Bridge (rev 51)
	00:18.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 15e8
	00:18.1 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 15e9
	00:18.2 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 15ea
	00:18.3 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 15eb
	00:18.4 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 15ec
	00:18.5 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 15ed
	00:18.6 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 15ee
	00:18.7 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 15ef
	01:00.0 Network controller: Realtek Semiconductor Co., Ltd. RTL8822BE 802.11a/b/g/n/ac WiFi adapter
	02:00.0 Non-Volatile memory controller: Lenovo Device 0006
	03:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 0e)
	03:00.1 Serial controller: Realtek Semiconductor Co., Ltd. Device 816a (rev 0e)
	03:00.2 Serial controller: Realtek Semiconductor Co., Ltd. Device 816b (rev 0e)
	03:00.3 IPMI Interface: Realtek Semiconductor Co., Ltd. Device 816c (rev 0e)
	03:00.4 USB controller: Realtek Semiconductor Co., Ltd. Device 816d (rev 0e)
	04:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 10)
	05:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Raven Ridge [Radeon Vega Series / Radeon Vega Mobile Series] (rev d0)
	05:00.1 Audio device: Advanced Micro Devices, Inc. [AMD/ATI] Device 15de
	05:00.2 Encryption controller: Advanced Micro Devices, Inc. [AMD] Device 15df
	05:00.3 USB controller: Advanced Micro Devices, Inc. [AMD] Device 15e0
	05:00.4 USB controller: Advanced Micro Devices, Inc. [AMD] Device 15e1
	05:00.6 Audio device: Advanced Micro Devices, Inc. [AMD] Device 15e3
	06:00.0 SATA controller: Advanced Micro Devices, Inc. [AMD] FCH SATA Controller [AHCI mode] (rev 61)

If more information is needed, I would be happy to provide.