Bug 1745333

Summary:	Infinite loop on Ryzen 3000 CPUs due to broken rdrand
Product:	[Fedora] Fedora	Reporter:	Miroslav Lichvar <mlichvar>
Component:	json-c	Assignee:	Björn Esser (besser82) <besser82>
Status:	CLOSED ERRATA	QA Contact:	Fedora Extras Quality Assurance <extras-qa>
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	30	CC:	besser82, h.reindl, igor.raits, jiri
Target Milestone:	---
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:	json-c-0.13.1-7.fc31 json-c-0.13.1-7.fc30	Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2019-11-15 03:01:41 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description Miroslav Lichvar 2019-08-25 13:01:51 UTC

Description of problem:
The rdrand instruction is apparently broken on some motherboards with the new Ryzen 3000 CPUs. This issue is supposed to be fixed by BIOS update, but that's not available for all boards yet.

json-c seems to use the rdrand in its initialization. On the broken boards it enters an infinite loop. This causes the boot to hang on systems with encrypted storage (due to cryptsetup using json-c?).

Please consider disabling the rdrand support in json-c. It doesn't seem to be very useful and causes problems. Alternatively, check first if rdrand is reported in /proc/cpuinfo to make the nordrand option effective for json-c.

A similar issue was in systemd (bug #1729268).

Version-Release number of selected component (if applicable):
json-c-0.13.1-4.fc30

Comment 1 Miroslav Lichvar 2019-11-06 16:37:08 UTC

Submitted pull request to disable rdrand support:
https://src.fedoraproject.org/rpms/json-c/pull-request/1

Comment 2 Björn Esser (besser82) 2019-11-09 20:02:29 UTC

PR has been merged, updates are on their way.  Thank you!

Comment 3 Fedora Update System 2019-11-09 20:04:32 UTC

FEDORA-2019-e06b410ade has been submitted as an update to Fedora 31. https://bodhi.fedoraproject.org/updates/FEDORA-2019-e06b410ade

Comment 4 Fedora Update System 2019-11-09 20:04:36 UTC

FEDORA-2019-f806bc58e5 has been submitted as an update to Fedora 30. https://bodhi.fedoraproject.org/updates/FEDORA-2019-f806bc58e5

Comment 5 Fedora Update System 2019-11-11 01:29:21 UTC

json-c-0.13.1-7.fc30 has been pushed to the Fedora 30 testing repository. If problems still persist, please make note of it in this bug report.
See https://fedoraproject.org/wiki/QA:Updates_Testing for
instructions on how to install test updates.
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2019-f806bc58e5

Comment 6 Fedora Update System 2019-11-11 01:38:20 UTC

json-c-0.13.1-7.fc31 has been pushed to the Fedora 31 testing repository. If problems still persist, please make note of it in this bug report.
See https://fedoraproject.org/wiki/QA:Updates_Testing for
instructions on how to install test updates.
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2019-e06b410ade

Comment 7 Harald Reindl 2019-11-11 11:53:47 UTC Comment hidden (abuse)

it's a terrible idea starting to disable usage of a cpu-instrction which exists since 2011 on Intel CPU#s beasue AMD is too supid to proerply implement it in their new CPU's years later, the same applies to TSX which ins braindead disabled in glibc because of a issue on years old cpus

Comment 8 Fedora Update System 2019-11-15 03:01:41 UTC

json-c-0.13.1-7.fc31 has been pushed to the Fedora 31 stable repository. If problems still persist, please make note of it in this bug report.

Comment 9 Fedora Update System 2019-11-23 01:12:14 UTC

json-c-0.13.1-7.fc30 has been pushed to the Fedora 30 stable repository. If problems still persist, please make note of it in this bug report.