Skip to main content

Missing Battery Information

In the last few days (or should i say weeks), i encountered strange problems on my laptop. I enabled the battery monitor on my KDE and i loaded battery modules, but after few hours of working with it, i lost the information about the battery. I asked ID-Slackware community but nobody experienced this. At first, i thought it was only happening on my system, but in fact, it's not. Everybody else has reported this on this and this (and probably more). It happened after i used 2.6.26.x kernels.

The solution is already on the latest Stable kernel, after reading commit from Intel developer, Zhao Yakui. Here's the commit info:
commit e6908f26e33567ebd565fad04096537a5853fec0
Author: Zhao Yakui
Date: Tue Sep 23 13:38:13 2008 +0800

ACPI: Avoid bogus EC timeout when EC is in Polling mode

commit 9d699ed92a459cb408e2577e8bbeabc8ec3989e1 upstream

When EC is in Polling mode, OS will check the EC status continually by using
the following source code:
clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
while (time_before(jiffies, delay)) {
if (acpi_ec_check_status(ec, event))
return 0;
But msleep is realized by the function of schedule_timeout. At the same time
although one process is already waken up by some events, it won't be scheduled
immediately. So maybe there exists the following phenomena:
a. The current jiffies is already after the predefined jiffies.
But before timeout happens, OS has no chance to check the EC
status again.
b. If preemptible schedule is enabled, maybe preempt schedule will happen
before checking loop. When the process is resumed again, maybe
timeout already happens, which means that OS has no chance to check
the EC status.

In such case maybe EC status is already what OS expects when timeout happens.
But OS has no chance to check the EC status and regards it as AE_TIME.

So it will be more appropriate that OS will try to check the EC status again
when timeout happens. If the EC status is what we expect, it won't be regarded
as timeout. Only when the EC status is not what we expect, it will be regarded
as timeout, which means that EC controller can't give a response in time.

Signed-off-by: Zhao Yakui
Signed-off-by: Zhang Rui
Signed-off-by: Andi Kleen
Signed-off-by: Greg Kroah-Hartman

Guess what? It's only two line of patches big grin

drivers/acpi/ec.c | 2 ++
1 file changed, 2 insertions(+)

Index: linux-2.6/drivers/acpi/ec.c
--- linux-2.6.orig/drivers/acpi/ec.c
+++ linux-2.6/drivers/acpi/ec.c
@@ -196,6 +196,8 @@ static int acpi_ec_wait(struct acpi_ec *
return 0;
+ if (acpi_ec_check_status(ec,event))
+ return 0;
pr_err(PREFIX "acpi_ec_wait timeout, status = 0x%2.2x, event = %s\n",

For those who had problems with battery information, i suggest you to upgrade to this version or just go straight to 2.6.27 which has just been released by Linus and let's hope you will find the cure for your problem. I haven't upgrade yet, since it just came out, but i will upgrade to check whether the solution is fixing my problem or not.

It's one of the advantage of reading Kernel changelog, even though i don't understand the rest of the changelog big grin.

Popular posts from this blog

Running Rsync Via Proxy

One way to get the latest Slackware updates is by running rsync to syncronize your local repository and the main repository that hold the Slackware packages. Eric Hameleers has provided a great script called and how i modified this tool has been discussed on my previous post. In general, it works, except for one problem, when your computer is connecting to the Internet through a proxy.

My workstation at my office is connected to the Internet through a proxy, so i can't use normal rsync to work normally. I browsed the web and i found this site which tells us about how we should modify our squid configuration to allow rsync connection from any computer from our local networks. I asked my sysadmin to try this script. He agreed and he updated the squid configuration on the proxy.

Next, i need to update my environment variable RSYNC_PROXY to the host of the proxy and also the port. Let's say you are running a proxy on and port 8080, then you need to run …

NVidia Legacy Unix Driver Update

NVidia has released an updated legacy drivers to support X.Org 1.19 with ABI 23. It has been mentioned in the UNIX drivers, but you can directly find the drivers from the links below:
NVidia 304.134 (x86x86_64)NVidia 340.101 (x86, x86_64) I have tested the 304.134 driver and it's working great here. I can finally remove x from my /etc/slackpkg/blacklist file since it's a showstopper for me.
Aside from legacy driver, NVidia has also released their latest driver 375.26 (x86, x86_64), which brings support for newer cards and also many new features (including X.Org 1.19 with ABI 23 support). 

Security Update: firefox, irssi, pidgin

Three security updates were released for today:
firefox: Upgraded to 45.4.0esr for 14.1 and 14.2 and 49.0 for currentirssi: Upgraded to 0.8.20pidgin: Upgraded to 2.10.11, 2.10.12, and 2.11.0 for all stable Slackware releases depending on their support Some minor update in current:
mkinitrd: Add dmsetup supportemacs: Upgraded to 25.1qt: Fix multilib issue network-scripts: Fix minor issue