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Diffstat (limited to 'content/2019-10-27-kernel-debugging-qemu/index.md')
| -rw-r--r-- | content/2019-10-27-kernel-debugging-qemu/index.md | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/content/2019-10-27-kernel-debugging-qemu/index.md b/content/2019-10-27-kernel-debugging-qemu/index.md index 518b3d5..bda445b 100644 --- a/content/2019-10-27-kernel-debugging-qemu/index.md +++ b/content/2019-10-27-kernel-debugging-qemu/index.md @@ -8,6 +8,8 @@ tags = ["linux", "qemu"] **EDIT**: - 2021-07-15: Added `Appendix: Dockerfile for Kernel development` and updated busybox + Kernel versions. +- 2023-11-23: Fix ramdisk vs ramfs ([ref][ramfs-vs-ramdisk]), and use + `devtmpfs` and updated busybox + Kernel versions. The other evening while starring at some Linux kernel code I thought, let me setup a minimal environment so I can easily step through the code and examine @@ -15,7 +17,7 @@ the state. I ended up creating: - a [Linux kernel][linux-kernel] with minimal configuration -- a minimal [ramdisk][initrd] to boot into which is based on [busybox][busybox] +- a minimal [initramfs][initramfs] to boot into which is based on [busybox][busybox] In the remaing part of this article we will go through each step by first building the kernel, then building the initrd and then running the kernel using @@ -31,7 +33,7 @@ This allows us to merge a fragment file into the current configuration by running the `scripts/kconfig/merge_config.sh` script. Let's quickly go over some customizations we do. -The following two lines enable support for gzipped initramdisks: +The following two lines enable support for gzipped initramfs: ```config CONFIG_BLK_DEV_INITRD=y CONFIG_RD_GZIP=y @@ -78,6 +80,7 @@ cat <<EOF > init mount -t proc none /proc mount -t sysfs none /sys +mount -t devtmpfs none /dev exec setsid cttyhack sh EOF @@ -217,6 +220,8 @@ docker run -it kernel-dev [linux-kernel]: https://www.kernel.org [initrd]: https://www.kernel.org/doc/html/latest/admin-guide/initrd.html +[ramfs]: https://www.kernel.org/doc/html/latest/filesystems/ramfs-rootfs-initramfs.html +[ramfs-vs-ramdisk]: https://www.kernel.org/doc/html/latest/filesystems/ramfs-rootfs-initramfs.html#ramfs-and-ramdisk [busybox]: https://busybox.net [qemu]: https://www.qemu.org [gdb]: https://www.gnu.org/software/gdb |