Bug 658544

Summary:	sys-kernel/gentoo-sources-4.17.x regression: kvm_ptp broken for Linux x86_32 guests
Product:	Gentoo Linux	Reporter:	Andreas Steinmetz <ast>
Component:	Current packages	Assignee:	Gentoo Kernel Bug Wranglers and Kernel Maintainers <kernel>
Status:	RESOLVED FIXED
Severity:	normal	Keywords:	InVCS
Priority:	Normal
Version:	unspecified
Hardware:	All
OS:	Linux
Whiteboard:	gentoo-sources 4.17-5
Package list:		Runtime testing required:	---
Attachments:	Local fix for ptp_kvm failure Upstream updated patch

Description Andreas Steinmetz 2018-06-19 22:46:52 UTC

Created attachment 536472 [details, diff]
Local fix for ptp_kvm failure

Well, I tried to send this to kvm@vger.kernel.org but it seems to be delivered to /dev/null if you're not subscribed...

setup_vsyscall_timeinfo() is only defined for x86_64, thus pvclock_set_pvti_cpu0_va() gets not called and as the result initialization of ptp_kvm fails.

Thus 32 bit guest userspace has no /dev/ptp0 device.

The attached patch at least works for me.

The regression occured somewhere between 4.14.13 and 4.17.2 (sorry, I don't have more details).

Comment 1 Mike Pagano gentoo-dev

2018-06-19 23:39:19 UTC

Do you want to subscribe and submit this upstream, or do you want us to do it on your behalf?

Comment 2 Andreas Steinmetz 2018-06-20 06:04:32 UTC

It would be very kind of you if you could notify upstream.

Comment 3 Mike Pagano gentoo-dev

2018-06-21 22:42:02 UTC

Created attachment 536750 [details, diff]
Upstream updated patch

Andreas,  can you test this patch from upstream concerning your issue and tell me if it fixes it?

Comment 4 Mike Pagano gentoo-dev

2018-06-25 12:40:38 UTC

I took out your patch from gentoo-sources, let me know if the upstream patch works, be nice to get it in with 4.17.3.

Comment 5 Andreas Steinmetz 2018-06-25 15:58:04 UTC

Confirmed, upstream patch works.

Comment 6 Mike Pagano gentoo-dev

2018-06-29 23:19:44 UTC

Tee'ed up for next gentoo-sources release

Comment 7 Mike Pagano gentoo-dev

2018-07-05 14:03:05 UTC

Included in gentoo-sources-4.17.4