On Sat, Jun 9, 2012 at 8:01 PM, Adam Lee <adam8157@xxxxxxxxx> wrote: > On Sat, Jun 09, 2012 at 04:19:15PM +0600, Aft nix wrote: >> Thank you for the tips. qemu is booting the kernel now. But it stops >> with a kernel panic. >> >> >From qemu console, >> >> [ 2.209887] EXT3-fs (sda): mounted filesystem with writeback data mode >> [ 2.210566] VFS: Mounted root (ext3 filesystem) readonly on device 8:0. >> [ 2.211393] Freeing unused kernel memory: 456k freed >> [ 2.242325] Write protecting the kernel text: 6240k >> [ 2.242614] Write protecting the kernel read-only data: 1820k >> [ 2.248007] Kernel panic - not syncing: No init found. Try passing >> init= option to kernel. See Linux Documentation/init.txt for guidance. >> [ 2.248492] Pid: 1, comm: swapper/0 Not tainted 3.4.0+ #3 >> [ 2.248596] Call Trace: >> [ 2.249743] [<c160db4f>] panic+0x81/0x17e >> [ 2.249843] [<c10012d5>] init_post+0x75/0xb0 >> [ 2.249942] [<c183a61a>] kernel_init+0x1e0/0x1ea >> [ 2.250028] [<c183a3df>] ? parse_early_options+0x35/0x35 >> [ 2.250237] [<c183a43a>] ? repair_env_string+0x5b/0x5b >> [ 2.250326] [<c1616cd6>] kernel_thread_helper+0x6/0xd >> ... >> My understanding is i have to put the init binary in my root fs. But >> i'm clueless about how to do that? > > You need a full system, kernel is just the core. > > I suggest you using Debian stable images for QEMU at > http://people.debian.org/~aurel32/qemu > (ref: http://wiki.debian.org/QEMU) > > Or, use busybox to build rootfs like what I am doing: > https://github.com/adam8157/kernel-studio > Hi Adam Thanks for the reply. Googling revealed other ways of debugging. I was not aware that KGDB was merged with linux in 2.6.26. I was under the impression that Linux does not allow kernel debugger in kernel source tree. If i compile a kernel with KGDB , and if i'm not developing for "other" archs like ppc/arm then there is little gain in qemu's gdb stub. Instead i can fire up a full distro in Virtualbox, configure a virtual serial console and "socat" from the host. This link : http://www.linuxforu.com/2011/03/kgdb-with-virtualbox-debug-live-kernel/ I'm trying to follow this link instead. I'm not experienced in this field, so my reasoning might be wrong. If it is, please comment on my approach. Cheers. > -- > Regards, > Adam Lee > -------------------------------- > E-mail: adam8157@xxxxxxxxx > Website: http://adam8157.info > -------------------------------- -- -aft _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
