tiomap-dev team mailing list archive
-
tiomap-dev team
-
Mailing list archive
-
Message #01647
[Bug 971091] Re: Pandaboard ES freezes with the default CPU scaling governor ondemand
Andy, do you have any update for this bug? I know Ubuntu is still using
3.2, but I remember we had to disable CPU_FREQ with 3.3 to get it to run
without freeze on 4460, so I'm not sure if the fix is already around
somewhere.
** Also affects: linaro-landing-team-ti
Importance: Undecided
Status: New
** Changed in: linaro-landing-team-ti
Status: New => Confirmed
--
You received this bug notification because you are a member of TI OMAP
Developers, which is subscribed to linaro-landing-team-ti.
https://bugs.launchpad.net/bugs/971091
Title:
Pandaboard ES freezes with the default CPU scaling governor ondemand
Status in Linaro Texas Instruments Landing Team:
Confirmed
Status in “linux-ti-omap4” package in Ubuntu:
Confirmed
Bug description:
Pandaboard ES freezes sporadically with the CPU scaling governor default setting, which is "ondemand".
It is a complete freeze, no syslog entry, no serial access, no network, no keyboard/mouse anymore. When pressing the reset button, it will not even reboot. The SD card interface seems to be hanging. Pulling and re-inserting the SD card before pressing the reset button, or a global power-cycle will re-boot the board properly.
The error occurs during normal operation on desktop, but can also be procuded in an unattended way:
1. Create a RAM disk by adding this to fstab
none /tmp tmpfs defaults,noatime,mode=1777,size=600M 0 0
2. Mount it and create a big file on the RAM disk:
dd bs=1M count=210 if=/dev/urandom of=/tmp/a
3. Change to /tmp and start an endless loop:
while true; do cp a b; date; sleep 3; done
Note that the "sleep" is important to cause the governor to switch CPU
speed up and down. Wait for 1 to 8 hrs and find the Pandaboard ES in
frozen state. You can do the same with a bigger file and /tmp on the
SD card. This will often produce the error faster (possibly due to CPU
idling at flash write delays) but will stress your flash card.
Setting the CPU scaling governor to "performance" completely solves the problem. I guess there might be a HW issue on the Pandaboard ES that kicks in with frequent CPU speed changes.
Solution proposal: set the CPU scaling governor to "performance" as default until the issue is further analysed.
ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: linux-image-3.2.0-1411-omap4 3.2.0-1411.14
ProcVersionSignature: Ubuntu 3.2.0-1411.14-omap4 3.2.9
Uname: Linux 3.2.0-1411-omap4 armv7l
ApportVersion: 1.95-0ubuntu1
Architecture: armhf
Date: Sun Apr 1 23:01:52 2012
ProcEnviron:
TERM=xterm
LANG=de_DE.UTF-8
SHELL=/bin/bash
SourcePackage: linux-ti-omap4
UpgradeStatus: No upgrade log present (probably fresh install)
To manage notifications about this bug go to:
https://bugs.launchpad.net/linaro-landing-team-ti/+bug/971091/+subscriptions