On Mon, 17 Oct 2011, James Westby wrote: > asac asked in a private mail thread about how to enable thumb2 on an > otherwise plain defconfig.
Two things: 1) If you want your kernel to support Thumb2 user space binaries, you must have CONFIG_ARM_THUMB=y in your kernel config. This is probably set as our user space has been compiled to Thumb2 for quite a while. 2) If you want your kernel itself to be a Thumb2 binary, then you must have CONFIG_THUMB2_KERNEL=y. This is however available only for ARMv7 and above. For example, in the OMAP case, you can't support OMAP2 with a Thumb2 kernel, therefore the CONFIG_THUMB2_KERNEL option will be visible only if OMAP2 support is configured out (OMAP3 + OMAP4 is fine). Also it is not necessary to match the kernel and user space "thumbness". However there was a bug in the kernel compiled for ARM mode when a Thumb mode user space was used with it when that kernel was configured for both ARMv6 and ARMv7 (e.g. omap2plus_defconfig). The fix was available in linux-linaro-3.0 but this was missing from linux-linaro-3.1 until a few hours ago. -- You received this bug notification because you are a member of Linaro Release Team, which is subscribed to the bug report. https://bugs.launchpad.net/bugs/859473 Title: CI kernels causing many "Illegal Instruction"s Status in LAVA Validation Lab: Invalid Status in LAVA Automated Testing Framework: Invalid Status in Linaro CI: Confirmed Bug description: Recently there have been lots of validation failures for kernels from CI. These failures manifest as "Illegal Instruction" errors all over the logs (not just during tests, but booting as well.) It seems that the kernel is causing a lot of SIGILLs, but we don't know why yet. To reproduce ------------ Combining http://ci.linaro.org/kernel_hwpack/omap3/hwpack_linaro-omap3_20111007-0028_armel_supported.tar.gz http://snapshots.linaro.org/11.05-daily/linaro-nano/20111005/1/images/tar/nano-n-tar-20111005-1.tar.gz with linaro-media-create (--rootfs ext2) should give you an image that shows the problem. Information wanted ------------------ There are currently two things that we would like more information on to try and narrow down the cause of the problem. 1) A core file from a crashing application To get this Create the image as described above Boot in to it Run "ulimit -c 1024" Run "hwclock" Watch it crash with "Illegal Instruction (core dumped)" Get that core from the filesystem. 2) Test a defconfig build If this succeeds then it suggests a problem with the way that the kernel is being built on ci.linaro.org. To do this Get the tip of linus' tree Build with omap2plus_defconfig Boot the resulting kernel If that shows no SIGILL problems, then try a cross-build from an x86 host. If neither of those show problems then we can concentrate on ci.linaro.org. To manage notifications about this bug go to: https://bugs.launchpad.net/lava-lab/+bug/859473/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~linaro-release Post to : [email protected] Unsubscribe : https://launchpad.net/~linaro-release More help : https://help.launchpad.net/ListHelp
