----- Forwarded message from Bryce Harrington <bryce at osdl.org> -----
Date: Fri, 29 Sep 2006 13:20:44 -0700
From: Bryce Harrington <bryce at osdl.org>
To: lhcs-devel at lists.sourceforge.net
Subject: Error message when onlining already-onlined cpu
Hi,
In testing hotplug cpu recently, I notice a discrepancy in how it's
handled on x86_64 vs. other architectures. Normally, if you attempt to
online an already onlined cpu, it returns an exit code of 1 but no error
message. However, on x86_64 it produces this error message:
x86_64:
# echo 1 > /sys/devices/system/cpu/cpu1/online
-bash: echo: write error: Invalid argument
# echo 0 > /sys/devices/system/cpu/cpu1/online
# echo 0 > /sys/devices/system/cpu/cpu1/online
-bash: echo: write error: Device or resource busy
# echo 1 > /sys/devices/system/cpu/cpu1/online
# echo 1 > /sys/devices/system/cpu/cpu1/online
-bash: echo: write error: Invalid argument
I think it should not be printing an error message in this case.
Here is sample output on a couple other architectures:
ia64, ppc64:
# echo 1 > /sys/devices/system/cpu/cpu1/online
# echo 1 > /sys/devices/system/cpu/cpu1/online
# echo $?
1
# echo 0 > /sys/devices/system/cpu/cpu1/online
# echo $?
0
# echo 1 > /sys/devices/system/cpu/cpu1/online
# echo $?
0
Test output that identified this issue:
http://crucible.osdl.org/runs/2271/test_output/lhcs_regression.log
Thanks,
Bryce
----- End forwarded message -----
