[PATCH v2 3/6] vm: build GPT images

9 Oct 2022

This will allow booting reliably from multiple disk images, without
relying on order or requiring udev in an initramfs.  (The only
deterministic way of doing boot order on Linux without special
userspace support is to set "root" on the kernel command line to
either a GPT partition UUID or label.)

Signed-off-by: Alyssa Ross <hi@alyssa.is>
---
 vm/app/catgirl/Makefile    | 13 ++++++++++---
 vm/app/catgirl/default.nix | 10 +++++++---
 vm/app/lynx/Makefile       | 13 ++++++++++---
 vm/app/lynx/default.nix    | 10 +++++++---
 vm/sys/net/Makefile        | 13 ++++++++++---
 vm/sys/net/default.nix     | 10 +++++++---
 6 files changed, 51 insertions(+), 18 deletions(-)

diff --git a/vm/app/catgirl/Makefile b/vm/app/catgirl/Makefile
index 9016745..8129c8e 100644
--- a/vm/app/catgirl/Makefile
+++ b/vm/app/catgirl/Makefile
@@ -8,6 +8,7 @@ QEMU_KVM = qemu-kvm
 CLOUD_HYPERVISOR = cloud-hypervisor
 
 VMM = qemu
+SCRIPTS = ../../../scripts
 
 HOST_FILES = host/data/appvm-catgirl/providers/net/netvm
 
@@ -33,9 +34,15 @@ build/host/data/appvm-catgirl/vmlinux: $(VMLINUX)
 	mkdir -p $$(dirname $@)
 	cp $(VMLINUX) $@
 
+build/host/data/appvm-catgirl/blk/root.img: $(SCRIPTS)/make-gpt.sh $(SCRIPTS)/sfdisk-field.awk build/rootfs.ext4
+	mkdir -p $$(dirname $@)
+	$(SCRIPTS)/make-gpt.sh $@.tmp \
+	    build/rootfs.ext4:4f68bce3-e8cd-4db1-96e7-fbcaf984b709:0d2f5f77-eb9c-453a-9463-daafcb5ce2b2:root
+	mv $@.tmp $@
+
 # tar2ext4 will leave half a filesystem behind if it's interrupted
 # half way through.
-build/host/data/appvm-catgirl/blk/root.img: build/rootfs.tar
+build/rootfs.ext4: build/rootfs.tar
 	mkdir -p $$(dirname $@)
 	tar2ext4 -i build/rootfs.tar -o $@.tmp
 	mv $@.tmp $@
@@ -95,7 +102,7 @@ build/etc/s6-rc: $(VM_S6_RC_FILES)
 run-qemu: build/host/data/appvm-catgirl/blk/root.img
 	$(QEMU_KVM) -m 128 -cpu host -machine q35,kernel=$(KERNEL) -vga none \
 	  -drive file=build/host/data/appvm-catgirl/blk/root.img,if=virtio,format=raw,readonly=on \
-	  -append "console=ttyS0 root=/dev/vda" \
+	  -append "console=ttyS0 root=PARTLABEL=root" \
 	  -netdev user,id=net0 \
 	  -device virtio-net,netdev=net0,mac=0A:B3:EC:00:00:00 \
 	  -chardev vc,id=virtiocon0 \
@@ -110,7 +117,7 @@ run-cloud-hypervisor: build/host/data/appvm-catgirl/blk/root.img
 	    --disk path=build/host/data/appvm-catgirl/blk/root.img,readonly=on \
 	    --net tap=tap0,mac=0A:B3:EC:00:00:00 \
 	    --kernel $(KERNEL) \
-	    --cmdline "console=ttyS0 root=/dev/vda" \
+	    --cmdline "console=ttyS0 root=PARTLABEL=root" \
 	    --console tty \
 	    --serial pty
 .PHONY: run-cloud-hypervisor
diff --git a/vm/app/catgirl/default.nix b/vm/app/catgirl/default.nix
index 61f1462..d83392d 100644
--- a/vm/app/catgirl/default.nix
+++ b/vm/app/catgirl/default.nix
@@ -1,5 +1,5 @@
 # SPDX-License-Identifier: MIT
-# SPDX-FileCopyrightText: 2021 Alyssa Ross <hi@alyssa.is>
+# SPDX-FileCopyrightText: 2021-2022 Alyssa Ross <hi@alyssa.is>
 
 { config ? import ../../../nix/eval-config.nix {}
 , terminfo ? config.pkgs.foot.terminfo
@@ -8,13 +8,15 @@
 config.pkgs.pkgsStatic.callPackage (
 
 { lib, stdenvNoCC, runCommand, writeReferencesToFile, buildPackages
-, s6-rc, tar2ext4
+, jq, s6-rc, tar2ext4, util-linux
 , busybox, cacert, catgirl, execline, kmod, mdevd, s6, s6-linux-init
 }:
 
 let
   inherit (lib) cleanSource cleanSourceWith concatMapStringsSep hasSuffix;
 
+  scripts = import ../../../scripts { inherit config; };
+
   packages = [
     catgirl execline kmod mdevd s6 s6-linux-init s6-rc
 
@@ -71,11 +73,13 @@ stdenvNoCC.mkDerivation {
     src = cleanSource ./.;
   };
 
-  nativeBuildInputs = [ s6-rc tar2ext4 ];
+  nativeBuildInputs = [ jq s6-rc tar2ext4 util-linux ];
 
   PACKAGES_TAR = packagesTar;
   VMLINUX = "${kernel.dev}/vmlinux";
 
+  makeFlags = [ "SCRIPTS=${scripts}" ];
+
   installPhase = ''
     mv build/svc $out
   '';
diff --git a/vm/app/lynx/Makefile b/vm/app/lynx/Makefile
index ff87cb8..ff42501 100644
--- a/vm/app/lynx/Makefile
+++ b/vm/app/lynx/Makefile
@@ -8,6 +8,7 @@ QEMU_KVM = qemu-kvm
 CLOUD_HYPERVISOR = cloud-hypervisor
 
 VMM = qemu
+SCRIPTS = ../../../scripts
 
 HOST_FILES = host/data/appvm-lynx/providers/net/netvm
 
@@ -33,9 +34,15 @@ build/host/data/appvm-lynx/vmlinux: $(VMLINUX)
 	mkdir -p $$(dirname $@)
 	cp $(VMLINUX) $@
 
+build/host/data/appvm-lynx/blk/root.img: $(SCRIPTS)/make-gpt.sh $(SCRIPTS)/sfdisk-field.awk build/rootfs.ext4
+	mkdir -p $$(dirname $@)
+	$(SCRIPTS)/make-gpt.sh $@.tmp \
+	    build/rootfs.ext4:4f68bce3-e8cd-4db1-96e7-fbcaf984b709:41e8068d-38d5-4135-ad77-0da704743940:root
+	mv $@.tmp $@
+
 # tar2ext4 will leave half a filesystem behind if it's interrupted
 # half way through.
-build/host/data/appvm-lynx/blk/root.img: build/rootfs.tar
+build/rootfs.ext4: build/rootfs.tar
 	mkdir -p $$(dirname $@)
 	tar2ext4 -i build/rootfs.tar -o $@.tmp
 	mv $@.tmp $@
@@ -94,7 +101,7 @@ build/etc/s6-rc: $(VM_S6_RC_FILES)
 run-qemu: build/host/data/appvm-lynx/blk/root.img
 	$(QEMU_KVM) -m 128 -cpu host -machine q35,kernel=$(KERNEL) -vga none \
 	  -drive file=build/host/data/appvm-lynx/blk/root.img,if=virtio,format=raw,readonly=on \
-	  -append "console=ttyS0 root=/dev/vda" \
+	  -append "console=ttyS0 root=PARTLABEL=root" \
 	  -netdev user,id=net0 \
 	  -device virtio-net,netdev=net0,mac=0A:B3:EC:00:00:00 \
 	  -chardev vc,id=virtiocon0 \
@@ -109,7 +116,7 @@ run-cloud-hypervisor: build/host/data/appvm-lynx/blk/root.img
 	    --disk path=build/host/data/appvm-lynx/blk/root.img,readonly=on \
 	    --net tap=tap0,mac=0A:B3:EC:00:00:00 \
 	    --kernel $(KERNEL) \
-	    --cmdline "console=ttyS0 root=/dev/vda" \
+	    --cmdline "console=ttyS0 root=PARTLABEL=root" \
 	    --console tty \
 	    --serial pty
 .PHONY: run-cloud-hypervisor
diff --git a/vm/app/lynx/default.nix b/vm/app/lynx/default.nix
index ba715ec..92635f3 100644
--- a/vm/app/lynx/default.nix
+++ b/vm/app/lynx/default.nix
@@ -1,5 +1,5 @@
 # SPDX-License-Identifier: MIT
-# SPDX-FileCopyrightText: 2021 Alyssa Ross <hi@alyssa.is>
+# SPDX-FileCopyrightText: 2021-2022 Alyssa Ross <hi@alyssa.is>
 
 { config ? import ../../../nix/eval-config.nix {}
 , terminfo ? config.pkgs.foot.terminfo
@@ -8,13 +8,15 @@
 config.pkgs.pkgsStatic.callPackage (
 
 { lib, stdenvNoCC, runCommand, writeReferencesToFile, buildPackages
-, s6-rc, tar2ext4
+, jq, s6-rc, tar2ext4, util-linux
 , busybox, cacert, execline, kmod, lynx, mdevd, s6, s6-linux-init
 }:
 
 let
   inherit (lib) cleanSource cleanSourceWith concatMapStringsSep hasSuffix;
 
+  scripts = import ../../../scripts { inherit config; };
+
   packages = [
     execline kmod lynx mdevd s6 s6-linux-init s6-rc
 
@@ -71,11 +73,13 @@ stdenvNoCC.mkDerivation {
     src = cleanSource ./.;
   };
 
-  nativeBuildInputs = [ s6-rc tar2ext4 ];
+  nativeBuildInputs = [ jq s6-rc tar2ext4 util-linux ];
 
   PACKAGES_TAR = packagesTar;
   VMLINUX = "${kernel.dev}/vmlinux";
 
+  makeFlags = [ "SCRIPTS=${scripts}" ];
+
   installPhase = ''
     mv build/svc $out
   '';
diff --git a/vm/sys/net/Makefile b/vm/sys/net/Makefile
index 0b5fe8f..2b9004b 100644
--- a/vm/sys/net/Makefile
+++ b/vm/sys/net/Makefile
@@ -8,6 +8,7 @@ QEMU_KVM = qemu-kvm
 CLOUD_HYPERVISOR = cloud-hypervisor
 
 VMM = qemu
+SCRIPTS = ../../../scripts
 
 HOST_BUILD_FILES = \
 	build/host/data/netvm/blk/root.img \
@@ -30,9 +31,15 @@ build/host/data/netvm/vmlinux: $(VMLINUX)
 	mkdir -p $$(dirname $@)
 	cp $(VMLINUX) $@
 
+build/host/data/netvm/blk/root.img: $(SCRIPTS)/make-gpt.sh $(SCRIPTS)/sfdisk-field.awk build/rootfs.ext4
+	mkdir -p $$(dirname $@)
+	$(SCRIPTS)/make-gpt.sh $@.tmp \
+	    build/rootfs.ext4:4f68bce3-e8cd-4db1-96e7-fbcaf984b709:ea21da27-0391-48da-9235-9d2ab2ca7844:root
+	mv $@.tmp $@
+
 # tar2ext4 will leave half a filesystem behind if it's interrupted
 # half way through.
-build/host/data/netvm/blk/root.img: build/rootfs.tar
+build/rootfs.ext4: build/rootfs.tar
 	mkdir -p $$(dirname $@)
 	tar2ext4 -i build/rootfs.tar -o $@.tmp
 	mv $@.tmp $@
@@ -100,7 +107,7 @@ build/etc/s6-rc: $(VM_S6_RC_FILES)
 run-qemu: build/host/data/netvm/blk/root.img
 	$(QEMU_KVM) -m 128 -cpu host -machine q35,kernel=$(KERNEL) -vga none \
 	  -drive file=build/host/data/netvm/blk/root.img,if=virtio,format=raw,readonly=on \
-	  -append "console=ttyS0 root=/dev/vda" \
+	  -append "console=ttyS0 root=PARTLABEL=root" \
 	  -netdev user,id=net0 \
 	  -device e1000e,netdev=net0 \
 	  -netdev user,id=net1 \
@@ -117,7 +124,7 @@ run-cloud-hypervisor: build/host/data/netvm/blk/root.img
 	    --disk path=build/host/data/netvm/blk/root.img,readonly=on \
 	    --net tap=tap0 tap=tap1,mac=0A:B3:EC:80:00:00 \
 	    --kernel $(KERNEL) \
-	    --cmdline "console=ttyS0 root=/dev/vda" \
+	    --cmdline "console=ttyS0 root=PARTLABEL=root" \
 	    --console tty \
 	    --serial pty
 .PHONY: run-cloud-hypervisor
diff --git a/vm/sys/net/default.nix b/vm/sys/net/default.nix
index dfc7c35..e9a2f05 100644
--- a/vm/sys/net/default.nix
+++ b/vm/sys/net/default.nix
@@ -1,5 +1,5 @@
 # SPDX-License-Identifier: MIT
-# SPDX-FileCopyrightText: 2021 Alyssa Ross <hi@alyssa.is>
+# SPDX-FileCopyrightText: 2021-2022 Alyssa Ross <hi@alyssa.is>
 
 { config ? import ../../../nix/eval-config.nix {}
 , terminfo ? config.pkgs.foot.terminfo
@@ -8,7 +8,7 @@
 config.pkgs.pkgsStatic.callPackage (
 
 { lib, stdenvNoCC, runCommand, writeReferencesToFile, buildPackages
-, s6-rc, tar2ext4, xorg
+, jq, s6-rc, tar2ext4, util-linux, xorg
 , busybox, connmanMinimal, dbus, execline, kmod, mdevd, nftables, s6
 , s6-linux-init
 }:
@@ -16,6 +16,8 @@ config.pkgs.pkgsStatic.callPackage (
 let
   inherit (lib) cleanSource cleanSourceWith concatMapStringsSep hasSuffix;
 
+  scripts = import ../../../scripts { inherit config; };
+
   connman = connmanMinimal;
 
   packages = [
@@ -80,11 +82,13 @@ stdenvNoCC.mkDerivation {
     src = cleanSource ./.;
   };
 
-  nativeBuildInputs = [ s6-rc tar2ext4 ];
+  nativeBuildInputs = [ jq s6-rc tar2ext4 util-linux ];
 
   PACKAGES_TAR = packagesTar;
   VMLINUX = "${kernel.dev}/vmlinux";
 
+  makeFlags = [ "SCRIPTS=${scripts}" ];
+
   installPhase = ''
     mv build/svc $out
   '';
-- 
2.37.1

    