On Thu, 28 Feb 2019 08:16:05 +0000, Greg KH gregkh@linuxfoundation.org wrote:
Hi both,
On Wed, Feb 27, 2019 at 04:36:39PM -0800, Daniel Verkamp wrote:
Hello,
In my testing of crosvm[1] with Linux 4.4.175, I am observing failures on a 'kevin' Chromebook (RK3399) device - the guest kernel does not even get to the point of printing its first messages, and the host seems to be spinning at 100% CPU in KVM_RUN.
I narrowed this down to the 4.4 stable backport of "arm64: KVM: Skip MMIO insn after emulation" - with this patch reverted, I can boot the guest kernel as normal again.
Unfortunately, I am unable to easily test with a newer upstream kernel (this board is using the Chrome OS kernel with many additional patches applied on top of 4.4), so I'm not sure if this issue was introduced in the mainline commit or only in the stable branch. Is it possible that this patch has other dependencies that were missed in the backport? It looks like it was part of a larger series, but only this patch got pulled for 4.4 stable.
Thanks for reporting this. I'll have a look ASAP.
It looks like this got pulled in by Sasha's bot which is why it was applied.
I have no objection to reverting this if it is causing problems, unless someone here really thinks it needs to remain in the tree?
Can we hold on a tiny bit so that I can verify we haven't regressed crosvm all the way into mainline?
Daniel, is there any chance you could test with kvmtool as well on your setup? You can easily compile it as a static binary and run it from ChromeOS with:
lkvm-static run -c 1 -p "earlycon=uart,mmio,0x3f8" -l Image
which should start a UP guest and drop you to a shell. In the meantime, I'm starting to build crosvm on my kevin running mainline.
Thanks,
M.