FS#47368 : [linux] 4.4.x Kernel BUG at mm/fileman.c:207 on XEN

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FS#47368 - [linux] 4.4.x Kernel BUG at mm/fileman.c:207 on XEN

Attached to Project: Arch Linux
Opened by Gonzalo Alonso (gonAlonso) - Sunday, 13 December 2015, 23:38 GMT
Last edited by Gerardo Exequiel Pozzi (djgera) - Tuesday, 29 March 2016, 01:54 GMT

Task Type	Bug Report
Category	Kernel
Status	Closed
Assigned To	Tobias Powalowski (tpowa) Thomas Bächler (brain0)
Architecture	All
Severity	Medium
Priority	Normal
Reported Version
Due in Version	Undecided
Due Date	Undecided
Percent Complete
Votes	0
Private	No

Details

I'm facing some problems since I installed ArchLinux. I've used Ubuntu, LFS and Gentoo in the past.

I'm using Plasma desktop 5.5.0, using default kernel on top of Xen 4.5.1.
My machine is an AMD fx-8320, 16GB of RAM and a Radeon 285 GPU, using radeon driver.

The issue is a kernel BUG screen when I try to reboot or powerdown. It shows a message of a bug on mm/filemap.c:207
Usually, it happens after using some virtual machines(Windows HVMs). Sometimes it fails on booting a VM, so I try to reboot and the bug arises.
Video performance is poor too. When I try to shrink or enlarge a window the hole system hangs for a second and then continues, desktop animations drag so does video playback.

I noticed the problem doesn't show on bare kernel without Xen, though. Anyway, Xen should isolate any DomU problem from Dom0 if any, shouldn't it?

I tried to compile a new kernel, just to test it, no luck. I've followed Xen guidelines on Arch Linux web, enabling EFI boot support on Xen by recompiling binutils [ https://wiki.archlinux.org/index.php/Xen#With_UEFI_support ]

I can't find any clue on the internet, and the only remarkable event on journalctl is the USB3 page fault:
##kernel: AMD-Vi: Event logged [IO_PAGE_FAULT device=02:00.0 domain=0x0011 address=0x00000000ae9f9880 flags=0x0010]