On Tue, Oct 18, 2011 at 12:34:33PM -0000, Scott Bambrough wrote: > Some notes from the LT's on Thumb2 kernels (CONFIG_THUMB2_KERNEL=y) > > TI: The LT tested it when Dave Martin sent out the call, it blows chunks > for us in power management patches on tracking --> > > ''From the crash dump, the faulting code seems to be: > > f503 7182 add.w r1, r3, #260 ; 0x104 > ** e851 0f00 ldrex r0, [r1] ** > f100 0001 add.w r0, r0, #1 > > r1 is 0x53555151, which is looks more likely to be garbage than to be a > real, but misaligned, address. I guess we'll need to figure out where > that value is coming from...'' > > It's stuck at the moment. > > Freescale: The LT is currently having some difficulties building the > kernel completely with Thumb2 instructions. The major reason is the > suspend/resume code which is very SoC specific and low level, uses ARM > instructions which they need to convert into thumb2 compatible firstly. > It's currently on their wish list.
omap3 had some problems of this sort. To avoid needless churn, we simply kept some of the affected code as ARM for now. See https://wiki.linaro.org/WorkingGroups/Kernel/Thumb2Guide#Firmware_Interactions for an example of how this was implemented. It is likely that most of all of the affected code can be made Thumb-2 compatible, but building selected snippets as ARM is a useful first step, and still allows the rest of the kernel to be build in Thumb-2. If you have a log from make -k, that would also be useful for identifying how to fix the build failures. Cheers ---Dave -- 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
