Upgrade Buildroot to 2021.02 LTS with Linux 4.19

Makefile

@@ -23,7 +23,7 @@ KUBERNETES_VERSION ?= $(shell egrep "DefaultKubernetesVersion =" pkg/minikube/co
 KIC_VERSION ?= $(shell egrep "Version =" pkg/drivers/kic/types.go | cut -d \" -f2)
 
 # Default to .0 for higher cache hit rates, as build increments typically don't require new ISO versions
-ISO_VERSION ?= v1.22.0-1628622362-12032
+ISO_VERSION ?= v1.22.0-1628974786-12268
 # Dashes are valid in semver, but not Linux packaging. Use ~ to delimit alpha/beta
 DEB_VERSION ?= $(subst -,~,$(RAW_VERSION))
 DEB_REVISION ?= 0
@@ -40,7 +40,7 @@ KVM_GO_VERSION ?= $(GO_VERSION:.0=)
 
 
 INSTALL_SIZE ?= $(shell du out/minikube-windows-amd64.exe | cut -f1)
-BUILDROOT_BRANCH ?= 2020.02.12
+BUILDROOT_BRANCH ?= 2021.02.4
 REGISTRY ?= gcr.io/k8s-minikube
 
 # Get git commit id
@@ -66,7 +66,7 @@ MINIKUBE_BUCKET ?= minikube/releases
 MINIKUBE_UPLOAD_LOCATION := gs://${MINIKUBE_BUCKET}
 MINIKUBE_RELEASES_URL=https://github.com/kubernetes/minikube/releases/download
 
-KERNEL_VERSION ?= 4.19.182
+KERNEL_VERSION ?= 4.19.202
 # latest from https://github.com/golangci/golangci-lint/releases 
 # update this only by running `make update-golint-version`
 GOLINT_VERSION ?= v1.41.1
@@ -282,8 +282,6 @@ minikube_iso: deploy/iso/minikube-iso/board/coreos/minikube/rootfs-overlay/usr/b
 		git clone --depth=1 --branch=$(BUILDROOT_BRANCH) https://github.com/buildroot/buildroot $(BUILD_DIR)/buildroot; \
 	fi;
 	$(MAKE) BR2_EXTERNAL=../../deploy/iso/minikube-iso minikube_defconfig -C $(BUILD_DIR)/buildroot
-	mkdir -p $(BUILD_DIR)/buildroot/output/build
-	echo "module buildroot.org/go" > $(BUILD_DIR)/buildroot/output/build/go.mod
 	$(MAKE) -C $(BUILD_DIR)/buildroot host-python
 	$(MAKE) -C $(BUILD_DIR)/buildroot
 	mv $(BUILD_DIR)/buildroot/output/images/rootfs.iso9660 $(BUILD_DIR)/minikube.iso

deploy/iso/minikube-iso/board/coreos/minikube/patches/go/1.15.15/dist-generate-stub-go.mod-in-workdir.patch

@@ -0,0 +1,78 @@
+From 2b512af2ddaae01926fdcc9056b71017cac2a8d2 Mon Sep 17 00:00:00 2001
+From: Tamir Duberstein <tamird@google.com>
+Date: Thu, 25 Feb 2021 16:44:46 -0500
+Subject: [PATCH] dist: generate stub go.mod in workdir
+
+(cherry picked from commit c6374f516206c02b905d0d76ee1a66dab6fcd212)
+---
+ src/cmd/dist/build.go | 26 ++++++--------------------
+ 1 file changed, 6 insertions(+), 20 deletions(-)
+
+diff --git a/src/cmd/dist/build.go b/src/cmd/dist/build.go
+index 9e2b4f33b8..e5a7f9e9c4 100644
+--- a/src/cmd/dist/build.go
++++ b/src/cmd/dist/build.go
+@@ -110,9 +110,6 @@ func xinit() {
+ 		fatalf("$GOROOT must be set")
+ 	}
+ 	goroot = filepath.Clean(b)
+-	if modRoot := findModuleRoot(goroot); modRoot != "" {
+-		fatalf("found go.mod file in %s: $GOROOT must not be inside a module", modRoot)
+-	}
+
+ 	b = os.Getenv("GOROOT_FINAL")
+ 	if b == "" {
+@@ -244,6 +241,9 @@ func xinit() {
+ 	os.Setenv("LANGUAGE", "en_US.UTF8")
+
+ 	workdir = xworkdir()
++	if err := ioutil.WriteFile(pathf("%s/go.mod", workdir), []byte("module bootstrap"), 0666); err != nil {
++		fatalf("cannot write stub go.mod: %s", err)
++	}
+ 	xatexit(rmworkdir)
+
+ 	tooldir = pathf("%s/pkg/tool/%s_%s", goroot, gohostos, gohostarch)
+@@ -1484,11 +1484,11 @@ func goCmd(goBinary string, cmd string, args ...string) {
+ 		goCmd = append(goCmd, "-p=1")
+ 	}
+
+-	run(goroot, ShowOutput|CheckExit, append(goCmd, args...)...)
++	run(workdir, ShowOutput|CheckExit, append(goCmd, args...)...)
+ }
+
+ func checkNotStale(goBinary string, targets ...string) {
+-	out := run(goroot, CheckExit,
++	out := run(workdir, CheckExit,
+ 		append([]string{
+ 			goBinary,
+ 			"list", "-gcflags=all=" + gogcflags, "-ldflags=all=" + goldflags,
+@@ -1498,7 +1498,7 @@ func checkNotStale(goBinary string, targets ...string) {
+ 		os.Setenv("GODEBUG", "gocachehash=1")
+ 		for _, target := range []string{"runtime/internal/sys", "cmd/dist", "cmd/link"} {
+ 			if strings.Contains(out, "STALE "+target) {
+-				run(goroot, ShowOutput|CheckExit, goBinary, "list", "-f={{.ImportPath}} {{.Stale}}", target)
++				run(workdir, ShowOutput|CheckExit, goBinary, "list", "-f={{.ImportPath}} {{.Stale}}", target)
+ 				break
+ 			}
+ 		}
+@@ -1590,20 +1590,6 @@ func checkCC() {
+ 	}
+ }
+
+-func findModuleRoot(dir string) (root string) {
+-	for {
+-		if fi, err := os.Stat(filepath.Join(dir, "go.mod")); err == nil && !fi.IsDir() {
+-			return dir
+-		}
+-		d := filepath.Dir(dir)
+-		if d == dir {
+-			break
+-		}
+-		dir = d
+-	}
+-	return ""
+-}
+-
+ func defaulttarg() string {
+ 	// xgetwd might return a path with symlinks fully resolved, and if
+ 	// there happens to be symlinks in goroot, then the hasprefix test

deploy/iso/minikube-iso/board/coreos/minikube/rootfs-overlay/etc/sysctl.d/90-cilium-rp_filter.conf

@@ -0,0 +1,2 @@
+net.ipv4.conf.lxc*.rp_filter = 0
+net.ipv4.conf.cilium_*.rp_filter = 0

deploy/iso/minikube-iso/configs/minikube_defconfig

@@ -18,13 +18,12 @@ BR2_ROOTFS_USERS_TABLES="$(BR2_EXTERNAL_MINIKUBE_PATH)/board/coreos/minikube/use
 BR2_ROOTFS_OVERLAY="$(BR2_EXTERNAL_MINIKUBE_PATH)/board/coreos/minikube/rootfs-overlay"
 BR2_LINUX_KERNEL=y
 BR2_LINUX_KERNEL_CUSTOM_VERSION=y
-BR2_LINUX_KERNEL_CUSTOM_VERSION_VALUE="4.19.182"
+BR2_LINUX_KERNEL_CUSTOM_VERSION_VALUE="4.19.202"
 BR2_LINUX_KERNEL_USE_CUSTOM_CONFIG=y
 BR2_LINUX_KERNEL_CUSTOM_CONFIG_FILE="$(BR2_EXTERNAL_MINIKUBE_PATH)/board/coreos/minikube/linux_defconfig"
 BR2_LINUX_KERNEL_LZ4=y
 BR2_LINUX_KERNEL_NEEDS_HOST_LIBELF=y
 BR2_PACKAGE_GZIP=y
-BR2_PACKAGE_LZ4=y
 BR2_PACKAGE_XZ=y
 BR2_PACKAGE_STRACE=y
 BR2_PACKAGE_SYSDIG=y
@@ -37,6 +36,9 @@ BR2_PACKAGE_SSHFS=y
 BR2_PACKAGE_XFSPROGS=y
 BR2_PACKAGE_PARTED=y
 BR2_PACKAGE_SYSSTAT=y
+BR2_PACKAGE_LUAJIT=y
+BR2_PACKAGE_LZ4=y
+BR2_PACKAGE_LZ4_PROGS=y
 BR2_PACKAGE_CA_CERTIFICATES=y
 BR2_PACKAGE_LIBOPENSSL_BIN=y
 BR2_PACKAGE_LIBCURL_CURL=y
@@ -58,7 +60,9 @@ BR2_PACKAGE_PSMISC=y
 BR2_PACKAGE_SYSTEMD_LOGIND=y
 BR2_PACKAGE_SYSTEMD_MACHINED=y
 BR2_PACKAGE_TAR=y
+BR2_PACKAGE_UTIL_LINUX_BINARIES=y
 BR2_PACKAGE_UTIL_LINUX_LOSETUP=y
+BR2_PACKAGE_UTIL_LINUX_NOLOGIN=y
 BR2_PACKAGE_UTIL_LINUX_NSENTER=y
 BR2_PACKAGE_UTIL_LINUX_SCHEDUTILS=y
 BR2_TARGET_ROOTFS_CPIO_GZIP=y

pkg/minikube/download/iso.go

@@ -40,7 +40,7 @@ const fileScheme = "file"
 // DefaultISOURLs returns a list of ISO URL's to consult by default, in priority order
 func DefaultISOURLs() []string {
 	v := version.GetISOVersion()
-	isoBucket := "minikube-builds/iso/12032"
+	isoBucket := "minikube-builds/iso/12268"
 	return []string{
 		fmt.Sprintf("https://storage.googleapis.com/%s/minikube-%s.iso", isoBucket, v),
 		fmt.Sprintf("https://github.com/kubernetes/minikube/releases/download/%s/minikube-%s.iso", v, v),

site/content/en/docs/commands/start.md

@@ -65,7 +65,7 @@ minikube start [flags]
       --insecure-registry strings         Insecure Docker registries to pass to the Docker daemon.  The default service CIDR range will automatically be added.
       --install-addons                    If set, install addons. Defaults to true. (default true)
       --interactive                       Allow user prompts for more information (default true)
-      --iso-url strings                   Locations to fetch the minikube ISO from. (default [https://storage.googleapis.com/minikube-builds/iso/12032/minikube-v1.22.0-1628622362-12032.iso,https://github.com/kubernetes/minikube/releases/download/v1.22.0-1628622362-12032/minikube-v1.22.0-1628622362-12032.iso,https://kubernetes.oss-cn-hangzhou.aliyuncs.com/minikube/iso/minikube-v1.22.0-1628622362-12032.iso])
+      --iso-url strings                   Locations to fetch the minikube ISO from. (default [https://storage.googleapis.com/minikube-builds/iso/12268/minikube-v1.22.0-1628974786-12268.iso,https://github.com/kubernetes/minikube/releases/download/v1.22.0-1628974786-12268/minikube-v1.22.0-1628974786-12268.iso,https://kubernetes.oss-cn-hangzhou.aliyuncs.com/minikube/iso/minikube-v1.22.0-1628974786-12268.iso])
       --keep-context                      This will keep the existing kubectl context and will create a minikube context.
       --kubernetes-version string         The Kubernetes version that the minikube VM will use (ex: v1.2.3, 'stable' for v1.21.3, 'latest' for v1.22.0-rc.0). Defaults to 'stable'.
       --kvm-gpu                           Enable experimental NVIDIA GPU support in minikube