From mboxrd@z Thu Jan 1 00:00:00 1970 From: shazalive@gmail.com (Shahbaz khan) Date: Thu, 29 Jun 2017 00:48:49 +0500 Subject: Qemu+busybox for kernel development In-Reply-To: References: Message-ID: To: kernelnewbies@lists.kernelnewbies.org List-Id: kernelnewbies.lists.kernelnewbies.org Hi Alexander, On Wed, Jun 28, 2017 at 1:46 PM, Alexander Kapshuk < alexander.kapshuk@gmail.com> wrote: > I am trying to setup a build environment where I can run the kernel and > see how the changes I have made to the kernel source work. > My understanding, based on googling, is that it is common practice in the > kernel community to use a virtualised environment for that purpose. > What I have done so far is create a ramfs that is built into the kernel, > as described here [1] and here [2]. > > [1] https://landley.net/writing/rootfs-howto.html > [2] https://git.kernel.org/pub/scm/linux/kernel/git/ > torvalds/linux.git/plain/Documentation/early-userspace/README?h=v4.12-rc7 > > a). I have generated a minimal initramfs_list file: > scripts/gen_initramfs_list.sh -d >usr/initramfs_list > Which looks like this: > # This is a very simple, default initramfs > > dir /dev 0755 0 0 > nod /dev/console 0600 0 0 c 5 1 > dir /root 0700 0 0 > # file /kinit usr/kinit/kinit 0755 0 0 > # slink /init kinit 0755 0 0 > slink /bin/sh busybox 777 0 0 > file /init /bin/busybox 755 0 0 > > b). Set CONFIG_INITRAMFS_SOURCE: > CONFIG_INITRAMFS_SOURCE="/home/sasha/linux/usr/initramfs_list" > > c). And had the kernel generate the initramfs image: > make > ... > GEN usr/initramfs_data.cpio.gz > CHK include/generated/compile.h > AS usr/initramfs_data.o > LD usr/built-in.o > ... > > When I run the kernel in qemu I get an error message which complains about > /etc/init.d/rcS missing. > Did you check initramfs for rc.S script? The kernel configuration, busybox configuration and the layout of initramfs (which should be /home/sasha/linux/usr/initramfs_list) should be consistent. If the kernel is asking for it then it is not consistent. > The posts online seem to suggest that this has got to do with the busybox > configuration. > So far, I have not been able to get my head around this problem. > Any points or suggestions would be much appreciated. > > Alexander Kapshuk. > > > _______________________________________________ > Kernelnewbies mailing list > Kernelnewbies at kernelnewbies.org > https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies > > Thank you. Shahbaz Khan -------------- next part -------------- An HTML attachment was scrubbed... URL: http://lists.kernelnewbies.org/pipermail/kernelnewbies/attachments/20170629/a8a3f6d9/attachment-0001.html