Re: svn commit: r313268 - head/sys/kern [through -r313271 for atomic_fcmpset use and later: fails on PowerMac G5 "Quad Core"; -r313266 works]

On 2017-Feb-28, at 10:13 PM, Mateusz Guzik <mjguzik at gmail.com> wrote:

On Sat, Feb 25, 2017 at 08:31:04PM +0100, Mateusz Guzik wrote:
>> On Sat, Feb 25, 2017 at 09:58:39AM -0800, Mark Millard wrote:
>>> Thus the PowerMac G5 so-called "Quad Core" is back to
>>> -r313254 without your patches. (The "Quad Core" really has
>>> two processors, each with 2 cores.)
>>> 
>> 
>> 
>> Thanks a lot for testing. I'll have to think what to do with it, worst
>> case I'll #ifdef changes with powerpc.
>> 
> 
> Should be fixed with r314474. Got a real powerpc to test on (60 cores),
> was able to lock it up in seconds. Now it is perfectly stablle.
> 
> -- 
> Mateusz Guzik <mjguzik gmail.com>

The updated so-called "Quad Core" PowerMac G5 used for
TARGET_ARCH=powerpc64 was able to do a self hosted
buildworld buildkernel for -r314479 just fine.

Thanks much for the fixes: Now I can track head again
for powerpc64.


Summary of the transition interval:

So for powerpc64 (and powerpc?) It is a good
idea to avoid anything that is after -r313254
and before -r314474 in head. (Would this be
appropriate for a UPDATING notice given its
span?)

There may be other architectures that might have
a similar status(?): the last fixes involved were
not in Machine Dependent code. (Some architectures
are apparently insensitive to the errors, such as
amd64).

===
Mark Millard
markmi at dsl-only.net