[Bug 1818162] [NEW] arm-smmu-v3 arm-smmu-v3.3.auto: CMD_SYNC timeout

Public bug reported:

[Impact]
During heavy load, the following message may appear on the console of a HiSilicon D06 system:

arm-smmu-v3 arm-smmu-v3.3.auto: CMD_SYNC timeout

This is due to a bug that can also impact system performance, as the CPU
is blocked until the timeout occurs.

[Test Case]
The Ubuntu server certification test suite hits this pretty reliably during the stress-ng tests, although I haven't narrowed it down to exactly which test yet.

[Regression Risk]
Limited to arm64 systems. This change has been upstream since 4.20 w/o any noticed regressions (based on lack of Fixes: commits). Regressions could manifest as a performance hit.

** Affects: linux (Ubuntu)
Importance: Undecided
Assignee: dann frazier (dannf)
Status: Confirmed

** Affects: linux (Ubuntu Bionic)
Importance: Undecided
Status: New

** Affects: linux (Ubuntu Cosmic)
Importance: Undecided
Status: New

** Also affects: linux (Ubuntu Cosmic)
Importance: Undecided
Status: New

** Also affects: linux (Ubuntu Bionic)
Importance: Undecided
Status: New

--
You received this bug notification because you are subscribed to linux
in Ubuntu.
Matching subscriptions: Bgg, Bmail, Nb
https://bugs.launchpad.net/bugs/1818162

Title:
arm-smmu-v3 arm-smmu-v3.3.auto: CMD_SYNC timeout

Status in linux package in Ubuntu:
Confirmed
Status in linux source package in Bionic:
New
Status in linux source package in Cosmic:
New

Bug description:
[Impact]
During heavy load, the following message may appear on the console of a HiSilicon D06 system:

arm-smmu-v3 arm-smmu-v3.3.auto: CMD_SYNC timeout

This is due to a bug that can also impact system performance, as the
CPU is blocked until the timeout occurs.

[Test Case]
The Ubuntu server certification test suite hits this pretty reliably during the stress-ng tests, although I haven't narrowed it down to exactly which test yet.

[Regression Risk]
Limited to arm64 systems. This change has been upstream since 4.20 w/o any noticed regressions (based on lack of Fixes: commits). Regressions could manifest as a performance hit.

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1818162/+subscriptions