Hi,
Unfortunately I can't really do much on the target - as I can't get to the point where I can log in (no ssh connection, no local keyboard, etc.) ... :-(. I may be able to try to debug it when run through qemu-arm ... have you ever tried that? I'll do some poking around to see if this is possible. Thanks, ... Russell On Thu, Jan 6, 2011 00:15 AM, Khem Raj <[email protected]> wrote: > On Wed, Jan 5, 2011 at 8:37 PM, Russell Morris <[email protected]> wrote: > > Hi, > > > > OK, a few more updates ... > > - I built using the angstrom-2008.1 distro, but I have the same issue. I > > also ran the helloworld application on the target as well, getting the > > error message "Illegal instruction" (the same as qemu, which I guess is > > good). > > > If you can reproduce the issue on target then I would suggest that run > the helloworld under gdb or gdbserver on target and see where its > happening. > > > - I found the .config file that you are referring to, and made this change. > > I built and ran the debug kernel, but no more information is provided > > (other than "Illegal instruction"). > > - as a side note, I have to edit sumversion.c to fix a "known" issue > > (http://linux.derkeiler.com/Mailing-Lists/Kernel/2007-05/msg08279.html). > > You may want to update this in the master branch. > > > > Any other ideas? > > > > Thanks, > > ... Russell > > > > > > > > > > On Wed, Jan 5, 2011 05:07 PM, Russell Morris <[email protected]> > > wrote: > >> Hi, > >> > >> > >> > >> A few answers / thoughts, below (marked with RMo). > >> > >> > >> > >> Thanks for all the help and suggestions! > >> > >> > >> > >> ... Russell > >> > >> > >> On Wed, Jan 5, 2011 02:23 PM, Khem Raj <[email protected]> wrote: > >> > >> > >> > > >> On Wed, Jan 5, 2011 at 10:49 AM, Russell Morris > >> > <[email protected]> wrote: > >> > > Hi, > >> > > > >> > > > >> > > > >> > > Let me try to answer a few questions in one email ... :-). First of > >> > > all, I tried the patch - unfortunately no joy. It does the same thing > >> > > as earlier builds - let me try to explain, which will hopefully also > >> > > answer the questions below. > >> > > > >> > > > >> > > > >> > > I applied the patch, and rebuilt from scratch with the minimal distro > >> > > (deleted the TMPDIR completely before building). I built the > >> > > helloworld-image, to get a statically linked executable, and also > >> > > because it's a pretty small (=faster) build. > >> > > >> > OK thats bad. Now can you recompile the kernel with user debugging > >> > enabled ? and reboot then it will dump lot more info on console on > >> > error you need to turn on CONFIG_DEBUG_USER in .config > >> > >> [RMo] Sorry, a dumb question here - but how do I do this? I can see > >> .config in the temp directory - is this where you want me to modify it? > >> > > >> > > > >> > > > >> > > > >> > > I then looked at the helloworld executable, and a few interesting > >> > > notes, > >> > > > >> > > - if I readelf -h helloworld, it reports "Version5 EABI" ... so I > >> > > assume arm5te still? > >> > > >> > thats EABI version it has nothing to do with ARM architecture versions > >> > >> [RMo] OK, thanks! > >> > > >> > > > >> > > - if I try to run helloworld using qemu-arm, it runs fine ... with no > >> > > cpu selected (but I did some checking, and the default cpu for > >> > > qemu-arm is the arm5te). If I try to run with a -cpu arm920t option I > >> > > get the error message "qemu: uncaught target signal 4 (Illegal > >> > > instruction) - core dumped" > >> > > > >> > > >> > OK good so it seems there is still some intructions generated which > >> > are not supported in armv4t > >> > >> [RMo] That's what it seems like. To confirm - what is the best way to test > >> this ... with qemu-arm, and/or on the target? Just trying to make sure I > >> test it in a way that makes sense! > >> > > >> > > - I was not able to run this on the target right now, as I'm not near > >> > > it ... but when I did before I either got a core dump (illegal > >> > > instruction), or it said basically that the file was not found > >> > > (depending on the executable I tried to run). > >> > > >> > Yes it wont change I think. > >> > >> [RMo] Definitely agreed. > >> > > >> > > > >> > > > >> > > > >> > > One more interesting fact - if I go inside TMPDIR, and then inside > >> > > work/armv4t-oe-linux-gnueabi/gcc-cross-4.5-r28.0+svnr167948/gcc-4_5-branch/testsuite/gcc.target/arm, > >> > > there is some sort of test file, with a filename of pr42235.c. Oddly > >> > > enough the first line in this file says ... /* { dg-options "-mthumb > >> > > -O2 -march=armv5te" } */ > >> > > >> > > >> > thats just a gcc dejaGNU regression testcase it does not mean anything > >> > for compiling the root file system > >> > >> [RMo] Ok, thanks! > >> > > > >> > > > >> > > Hopefully this all makes sense. I think this says that the executable > >> > > is still targeting an armv5te ... but I could be wrong! Unfortunately > >> > > it wouldn't be the first time I was off base, and certaintly it won't > >> > > be the last ... :-(. > >> > > > >> > > > >> > > > >> > > Thanks for all your help! > >> > > >> > as koen suggested try it with angstrom-2008 and see if that helps too. > >> > >> [RMo] Absolutely - started already. I thought you were looking for the > >> minimal distro, but I may have misunderstood. In any case, trying this now > >> ... :-). > >> > > >> > > > >> > > > >> > > > >> > > ... Russell > >> > > > >> > > > >> > > > >> > > > >> > > > >> > > > >> > > On Wed, Jan 5, 2011 11:45 AM, Khem Raj <[email protected]> wrote: > >> > > > >> > > > >> > >> > >> > > On Wed, Jan 5, 2011 at 7:11 AM, Phil Blundell <[email protected]> wrote: > >> > >> > On Wed, 2011-01-05 at 08:48 -0600, Russell Morris wrote: > >> > >> >> Just to confirm - have you run these on an armv4t target? Only > >> > >> >> asking because my build completes fine, but the executables don't > >> > >> >> seem to run on the target. > >> > >> > > >> > >> > What exactly happens when you try to run those executables? Have > >> > >> > you > >> > >> > inspected them to see if they look like the right kind of thing, > >> > >> > and/or > >> > >> > compared them to working ones? > >> > >> > > >> > >> > p. > >> > >> > > >> > >> > > >> > >> > >> > >> > >> > >> yes as Phil asked you should try to localize the offending code in the > >> > >> faulty binary. So try to enable > >> > >> kernel debugging messages so it tells you where its faulting. > >> > >> Secondly if you can take a working system > >> > >> and see if the new binary faults in same way ? if not then link the > >> > >> binary statically and run it again on working > >> > >> system and see if it faults again. If it does then you can debug it > >> > >> > > >> > >> > _______________________________________________ > >> > >> > Openembedded-devel mailing list > >> > >> > [email protected] > >> > >> > http://lists.linuxtogo.org/cgi-bin/mailman/listinfo/openembedded-devel > >> > >> > > >> > >> > >> > >> _______________________________________________ > >> > >> Openembedded-devel mailing list > >> > >> [email protected] > >> > >> http://lists.linuxtogo.org/cgi-bin/mailman/listinfo/openembedded-devel > >> > >> > >> > > _______________________________________________ > >> > > Openembedded-devel mailing list > >> > > [email protected] > >> > > http://lists.linuxtogo.org/cgi-bin/mailman/listinfo/openembedded-devel > >> > > > >> > > >> > _______________________________________________ > >> > Openembedded-devel mailing list > >> > [email protected] > >> > http://lists.linuxtogo.org/cgi-bin/mailman/listinfo/openembedded-devel > >> > > >> _______________________________________________ > >> Openembedded-devel mailing list > >> [email protected] > >> http://lists.linuxtogo.org/cgi-bin/mailman/listinfo/openembedded-devel > >> > > _______________________________________________ > > Openembedded-devel mailing list > > [email protected] > > http://lists.linuxtogo.org/cgi-bin/mailman/listinfo/openembedded-devel > > > > _______________________________________________ > Openembedded-devel mailing list > [email protected] > http://lists.linuxtogo.org/cgi-bin/mailman/listinfo/openembedded-devel > _______________________________________________ Openembedded-devel mailing list [email protected] http://lists.linuxtogo.org/cgi-bin/mailman/listinfo/openembedded-devel
