Aneesh Kumar K.V wrote: > On Wed, May 20, 2009 at 10:57:21AM +0200, Jan Kiszka wrote: >> Aneesh Kumar K.V wrote: >>> On Wed, May 20, 2009 at 10:10:59AM +0200, Jan Kiszka wrote: >>>> Aneesh Kumar K.V wrote: >>>>> On Wed, May 20, 2009 at 12:23:12AM +0530, Aneesh Kumar K.V wrote: >>>>>> Hi, >>>>>> >>>>>> With the latest qemu-kvm and 2.6.30-rc6 kernel i am not able to get >>>>>> the guest debugging with gdb. I get the following error. >>>>>> >>>>>> $gdb ./vmlinux >>>>>> GNU gdb 6.8-debian >>>>>> Copyright (C) 2008 Free Software Foundation, Inc. >>>>>> License GPLv3+: GNU GPL version 3 or later >>>>>> <http://gnu.org/licenses/gpl.html> >>>>>> This is free software: you are free to change and redistribute it. >>>>>> There is NO WARRANTY, to the extent permitted by law. Type "show >>>>>> copying" >>>>>> and "show warranty" for details. >>>>>> This GDB was configured as "i486-linux-gnu"... >>>>>> (gdb) b do_fork >>>>>> Breakpoint 1 at 0xc106cfc8: file kernel/fork.c, line 1347. >>>>>> (gdb) target remote localhost:1234 >>>>>> Remote debugging using localhost:1234 >>>>>> [New Thread 1] >>>>>> Remote 'g' packet reply is too long: >>>>>> 7fa5000000000000000000000000000057e209c10000000004000000000000000000000000000000c8b3d0c100000000c03fd1c100000000a83fd1c10000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000912d03c1000000000202000060000000680000007b0000007b000000d8000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000f60b801540000000000000000000007f030000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000 > 000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000 >> 00 >>>> 0000000000000000000000000000000000000000000000000000000000000000000000000000000000000 >>>>>> (gdb) >>>>>> >>>>>> any patches that i can try ? >>>>> Works better with the four patches found at >>>>> >>>>> http://git.kiszka.org/?p=kvm-userspace.git;a=shortlog;h=refs/heads/queues/gdb >>>>> >>>>> But a next and continue doesn't get the prompt back on gdb. The guest >>>>> does stops the execution. >>>> What arch is host and guest (x86-32 or -64)? What KVM versions are you >>>> using? Are you sure that guest and vmlinux matches? >>>> >>> Both host and guest are x86-32. For kvm user space I did a git clone >>> from git://git.kernel.org/pub/scm/virt/kvm/qemu-kvm.git. I tested with >>> commit 22d239bcee126742df46938ee8ddc7c6b9209e23. That version fails >>> with the "remote g packet reply is too long" error. Then i applied the >>> four patches from your git repo. That gets the guest to stop execution >>> on breakpoint, i can check the stack. but single stepping doesn't work. >>> >>> Guest kernel I tried was linux-2.6-tip >> Does debugging work with -no-kvm, ie. in TCG mode? > > > Yes. debugging works with -no-kvm option. I can do single stepping. > Sigh, confirmed, there is a regression in qemu-kvm. Will dig into this. Older kvm-userspace should be fine (e.g. the last version you can pull from my tree). Jan -- Siemens AG, Corporate Technology, CT SE 2 Corporate Competence Center Embedded Linux -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
