[B][C][SRU][PATCH 0/1] Remove Power9 copy_unaligned test

Po-Hsu Lin po-hsu.lin at canonical.com
Tue May 14 09:00:58 UTC 2019

BugLink: https://bugs.launchpad.net/bugs/1813118

== Justification ==
The copy_unaligned / paste_unaligned / paste_last_unaligned test in
powerpc/alignment will fail on a Power9 node as which implements ISA
3.0B, but the test was designed base on ISA 3.0.

>From the commit message:
This is a test of the ISA 3.0 "copy" instruction. That instruction has
an L field, which if set to 1 specifies that "the instruction
identifies the beginning of a move group" (pp 858). That's also
referred to as "copy first" vs "copy".

In ISA 3.0B the copy instruction does not have an L field, and the
corresponding bit in the instruction must be set to 1.

This test is generating a "copy" instruction, not a "copy first", and
so on Power9 (which implements 3.0B), this results in an illegal

So just drop the test entirely. We still have copy_first_unaligned to
test the "copy first" behaviour.

== Fix ==
* 83039f22 (selftests/powerpc: Remove Power9 copy_unaligned test)

Patch can be cherry-picked into C, for Bionic it needs patches for bug
1828935 to land first (8d191587) to make it a clean cherry-pick.

It's already landed in D and onward.

== Test ==
Tested on a Power9 server with Cosmic, the broken tests will be removed

== Regression Potential ==
Code change limited to testing tools and just removing broken tests.
We still have copy_first_unaligned to test the "copy first" behaviour.

Michael Ellerman (1):
  selftests/powerpc: Remove Power9 copy_unaligned test

 .../testing/selftests/powerpc/alignment/.gitignore |  1 -
 tools/testing/selftests/powerpc/alignment/Makefile |  2 +-
 .../selftests/powerpc/alignment/copy_unaligned.c   | 41 ----------------------
 3 files changed, 1 insertion(+), 43 deletions(-)
 delete mode 100644 tools/testing/selftests/powerpc/alignment/copy_unaligned.c


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