On Tue, Jun 07, 2011 at 10:49:51AM +0100, Tixy wrote:
On Tue, 2011-06-07 at 10:01 +0100, Andy Green wrote:
On 06/07/2011 09:35 AM, Somebody in the thread at some point said:
Disabling Thumb2 fixes the problem.
What did you actually disable? Presumably not CONFIG_THUMB2_KERNEL so the thumb support at all?
I deselected CONFIG_THUMB2_KERNEL using menuconfig, which changed the .config file like...
-CONFIG_THUMB2_KERNEL=y
Yeah but where did this config come from?
It was the output produced by running the commands listed at https://wiki.linaro.org/Resources/HowTo/KernelDeploy#From_Linaro_sources
This config has CONFIG_THUMB2_KERNEL=y and doesn't have an entry for CONFIG_CPU_V6
Regenerating omap2plus_defconfig as I showed doesn't allow CONFIG_THUMB2_KERNEL to be configured because CONFIG_CPU_V6 is set (along with V7) since omap2plus_defconfig has a bunch of different cores supported.
You mentioned -->
"The .config I'm using is that described on the wiki at https://wiki.linaro.org/Resources/HowTo/KernelDeploy#From_Linaro_sources"
it also recommends
make ARCH=arm CROSS_COMPILE=arm-linux-gnueabi- omap2plus_defconfig
When I run that command I end up with a .config which has CONFIG_CPU_V6=y and no entry for CONFIG_THUMB2_KERNEL.
I just confirmed that's the case with current linux-linaro-2.6.39. Am I going nuts :?)
No, were using two different methods to produce configs. The one I use produces a Thumb2 kernel, the one you use doesn't.
Well, it seems we have a few different problems here:
Certainly, it looks like there is some kernel bug related to Thumb-2.
Andy's "SIGILL" symptom is probably something else though.
Finally, we're not all using the same configuration, which is causing confusion. There are at least two sources for the config:
* The debian.linaro/config/...config.* files from the packaged linaro kernel tree (at least me, Tixy and the packaged kernel use this)
* omap2plus_defconfig (omap upstream and some other people use this)
I'm not sure if there's a correct answer to that one ... but we should be careful to explain more carefully what config we're using when discussing kernel problems (I'm guilty of being a bit vague on this...)
Does anyone have a strong view on which config we should be using?
Cheers ---Dave