Re: port-arm/52603: arm(v7?) vfp register corruption

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

The following reply was made to PR port-arm/52603; it has been noted by GNATS.

From: Manuel Bouyer <bouyer%antioche.eu.org@localhost>
To: port-arm-maintainer%NetBSD.org@localhost, gnats-bugs%NetBSD.org@localhost,
        netbsd-bugs%NetBSD.org@localhost
Cc: 
Subject: Re: port-arm/52603: arm(v7?) vfp register corruption
Date: Mon, 9 Oct 2017 21:07:11 +0200

 On Mon, Oct 09, 2017 at 08:51:36PM +0200, Manuel Bouyer wrote:
 > running
 > ./fptest 3
 > without opencpn, on an otherwise idle board didn't show corruption after
 > 24h. But starting a ping -f against the board caused the corruption to
 > show up in less than half an hour.
 > 
 > So it looks like interrupt activity (other than the CPU ticks) is needed to
 > trigger the problem.
 
 Some interresting patterns:
 7: 107.700000 0.000000 107.700000
 17: 118.700000 117.600000 118.700000
 18: 119.800000 1.100000 119.800000
 
 the '17' line looks just as if a previous value of the register from the
 same process had been restored
 
 27: 129.700000 129.700000 217.600000
 
 here the wrong value looks like comming from another instance of the
 test program.
 
 -- 
 Manuel Bouyer <bouyer%antioche.eu.org@localhost>
      NetBSD: 26 ans d'experience feront toujours la difference
 --