feat: failsafe mode (#952)

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Co-authored-by: Adam Shiervani <adam.shiervani@gmail.com>

cmd/main.go

@@ -74,7 +74,12 @@ func supervise() error {
 	// run the child binary
 	cmd := exec.Command(binPath)
 
-	cmd.Env = append(os.Environ(), []string{envChildID + "=" + kvm.GetBuiltAppVersion()}...)
+	lastFilePath := filepath.Join(errorDumpDir, errorDumpLastFile)
+
+	cmd.Env = append(os.Environ(), []string{
+		fmt.Sprintf("%s=%s", envChildID, kvm.GetBuiltAppVersion()),
+		fmt.Sprintf("JETKVM_LAST_ERROR_PATH=%s", lastFilePath),
+	}...)
 	cmd.Args = os.Args
 
 	logFile, err := os.CreateTemp("", "jetkvm-stdout.log")

failsafe.go

@@ -0,0 +1,107 @@
+package kvm
+
+import (
+	"fmt"
+	"os"
+	"strings"
+	"sync"
+)
+
+const (
+	failsafeDefaultLastCrashPath = "/userdata/jetkvm/crashdump/last-crash.log"
+	failsafeFile                 = "/userdata/jetkvm/.enablefailsafe"
+	failsafeLastCrashEnv         = "JETKVM_LAST_ERROR_PATH"
+	failsafeEnv                  = "JETKVM_FORCE_FAILSAFE"
+)
+
+var (
+	failsafeOnce       sync.Once
+	failsafeCrashLog   = ""
+	failsafeModeActive = false
+	failsafeModeReason = ""
+)
+
+type FailsafeModeNotification struct {
+	Active bool   `json:"active"`
+	Reason string `json:"reason"`
+}
+
+// this function has side effects and can be only executed once
+func checkFailsafeReason() {
+	failsafeOnce.Do(func() {
+		// check if the failsafe environment variable is set
+		if os.Getenv(failsafeEnv) == "1" {
+			failsafeModeActive = true
+			failsafeModeReason = "failsafe_env_set"
+			return
+		}
+
+		// check if the failsafe file exists
+		if _, err := os.Stat(failsafeFile); err == nil {
+			failsafeModeActive = true
+			failsafeModeReason = "failsafe_file_exists"
+			_ = os.Remove(failsafeFile)
+			return
+		}
+
+		// get the last crash log path from the environment variable
+		lastCrashPath := os.Getenv(failsafeLastCrashEnv)
+		if lastCrashPath == "" {
+			lastCrashPath = failsafeDefaultLastCrashPath
+		}
+
+		// check if the last crash log file exists
+		l := failsafeLogger.With().Str("path", lastCrashPath).Logger()
+		fi, err := os.Lstat(lastCrashPath)
+		if err != nil {
+			if !os.IsNotExist(err) {
+				l.Warn().Err(err).Msg("failed to stat last crash log")
+			}
+			return
+		}
+
+		if fi.Mode()&os.ModeSymlink != os.ModeSymlink {
+			l.Warn().Msg("last crash log is not a symlink, ignoring")
+			return
+		}
+
+		// open the last crash log file and find if it contains the string "panic"
+		content, err := os.ReadFile(lastCrashPath)
+		if err != nil {
+			l.Warn().Err(err).Msg("failed to read last crash log")
+			return
+		}
+
+		// unlink the last crash log file
+		failsafeCrashLog = string(content)
+		_ = os.Remove(lastCrashPath)
+
+		// TODO: read the goroutine stack trace and check which goroutine is panicking
+		if strings.Contains(failsafeCrashLog, "runtime.cgocall") {
+			failsafeModeActive = true
+			failsafeModeReason = "video"
+			return
+		}
+	})
+}
+
+func notifyFailsafeMode(session *Session) {
+	if !failsafeModeActive || session == nil {
+		return
+	}
+
+	jsonRpcLogger.Info().Str("reason", failsafeModeReason).Msg("sending failsafe mode notification")
+
+	writeJSONRPCEvent("failsafeMode", FailsafeModeNotification{
+		Active: true,
+		Reason: failsafeModeReason,
+	}, session)
+}
+
+func rpcGetFailsafeLogs() (string, error) {
+	if !failsafeModeActive {
+		return "", fmt.Errorf("failsafe mode is not active")
+	}
+
+	return failsafeCrashLog, nil
+}

internal/native/cgo_linux.go

@@ -1,5 +1,8 @@
 //go:build linux
 
+// TODO: use a generator to generate the cgo code for the native functions
+// there's too much boilerplate code to write manually
+
 package native
 
 import (
@@ -46,7 +49,17 @@ static inline void jetkvm_cgo_setup_rpc_handler() {
 */
 import "C"
 
-var cgoLock sync.Mutex
+var (
+	cgoLock     sync.Mutex
+	cgoDisabled bool
+)
+
+func setCgoDisabled(disabled bool) {
+	cgoLock.Lock()
+	defer cgoLock.Unlock()
+
+	cgoDisabled = disabled
+}
 
 //export jetkvm_go_video_state_handler
 func jetkvm_go_video_state_handler(state *C.jetkvm_video_state_t) {
@@ -91,6 +104,10 @@ func jetkvm_go_rpc_handler(method *C.cchar_t, params *C.cchar_t) {
 var eventCodeToNameMap = map[int]string{}
 
 func uiEventCodeToName(code int) string {
+	if cgoDisabled {
+		return ""
+	}
+
 	name, ok := eventCodeToNameMap[code]
 	if !ok {
 		cCode := C.int(code)
@@ -103,6 +120,10 @@ func uiEventCodeToName(code int) string {
 }
 
 func setUpNativeHandlers() {
+	if cgoDisabled {
+		return
+	}
+
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -114,6 +135,10 @@ func setUpNativeHandlers() {
 }
 
 func uiInit(rotation uint16) {
+	if cgoDisabled {
+		return
+	}
+
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -123,6 +148,10 @@ func uiInit(rotation uint16) {
 }
 
 func uiTick() {
+	if cgoDisabled {
+		return
+	}
+
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -130,6 +159,10 @@ func uiTick() {
 }
 
 func videoInit(factor float64) error {
+	if cgoDisabled {
+		return nil
+	}
+
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -143,6 +176,10 @@ func videoInit(factor float64) error {
 }
 
 func videoShutdown() {
+	if cgoDisabled {
+		return
+	}
+
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -150,6 +187,10 @@ func videoShutdown() {
 }
 
 func videoStart() {
+	if cgoDisabled {
+		return
+	}
+
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -157,6 +198,10 @@ func videoStart() {
 }
 
 func videoStop() {
+	if cgoDisabled {
+		return
+	}
+
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -164,6 +209,10 @@ func videoStop() {
 }
 
 func videoLogStatus() string {
+	if cgoDisabled {
+		return ""
+	}
+
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -174,6 +223,10 @@ func videoLogStatus() string {
 }
 
 func uiSetVar(name string, value string) {
+	if cgoDisabled {
+		return
+	}
+
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -187,6 +240,10 @@ func uiSetVar(name string, value string) {
 }
 
 func uiGetVar(name string) string {
+	if cgoDisabled {
+		return ""
+	}
+
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -197,6 +254,10 @@ func uiGetVar(name string) string {
 }
 
 func uiSwitchToScreen(screen string) {
+	if cgoDisabled {
+		return
+	}
+
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -206,6 +267,10 @@ func uiSwitchToScreen(screen string) {
 }
 
 func uiGetCurrentScreen() string {
+	if cgoDisabled {
+		return ""
+	}
+
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -214,6 +279,10 @@ func uiGetCurrentScreen() string {
 }
 
 func uiObjAddState(objName string, state string) (bool, error) {
+	if cgoDisabled {
+		return false, nil
+	}
+
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -226,6 +295,10 @@ func uiObjAddState(objName string, state string) (bool, error) {
 }
 
 func uiObjClearState(objName string, state string) (bool, error) {
+	if cgoDisabled {
+		return false, nil
+	}
+
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -238,6 +311,10 @@ func uiObjClearState(objName string, state string) (bool, error) {
 }
 
 func uiGetLVGLVersion() string {
+	if cgoDisabled {
+		return ""
+	}
+
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -246,6 +323,10 @@ func uiGetLVGLVersion() string {
 
 // TODO: use Enum instead of string but it's not a hot path and performance is not a concern now
 func uiObjAddFlag(objName string, flag string) (bool, error) {
+	if cgoDisabled {
+		return false, nil
+	}
+
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -258,6 +339,10 @@ func uiObjAddFlag(objName string, flag string) (bool, error) {
 }
 
 func uiObjClearFlag(objName string, flag string) (bool, error) {
+	if cgoDisabled {
+		return false, nil
+	}
+
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -278,6 +363,10 @@ func uiObjShow(objName string) (bool, error) {
 }
 
 func uiObjSetOpacity(objName string, opacity int) (bool, error) {
+	if cgoDisabled {
+		return false, nil
+	}
+
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -289,6 +378,10 @@ func uiObjSetOpacity(objName string, opacity int) (bool, error) {
 }
 
 func uiObjFadeIn(objName string, duration uint32) (bool, error) {
+	if cgoDisabled {
+		return false, nil
+	}
+
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -301,6 +394,10 @@ func uiObjFadeIn(objName string, duration uint32) (bool, error) {
 }
 
 func uiObjFadeOut(objName string, duration uint32) (bool, error) {
+	if cgoDisabled {
+		return false, nil
+	}
+
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -313,6 +410,10 @@ func uiObjFadeOut(objName string, duration uint32) (bool, error) {
 }
 
 func uiLabelSetText(objName string, text string) (bool, error) {
+	if cgoDisabled {
+		return false, nil
+	}
+
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -330,6 +431,10 @@ func uiLabelSetText(objName string, text string) (bool, error) {
 }
 
 func uiImgSetSrc(objName string, src string) (bool, error) {
+	if cgoDisabled {
+		return false, nil
+	}
+
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -345,6 +450,10 @@ func uiImgSetSrc(objName string, src string) (bool, error) {
 }
 
 func uiDispSetRotation(rotation uint16) (bool, error) {
+	if cgoDisabled {
+		return false, nil
+	}
+
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -357,6 +466,10 @@ func uiDispSetRotation(rotation uint16) (bool, error) {
 }
 
 func videoGetStreamQualityFactor() (float64, error) {
+	if cgoDisabled {
+		return 0, nil
+	}
+
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -365,6 +478,10 @@ func videoGetStreamQualityFactor() (float64, error) {
 }
 
 func videoSetStreamQualityFactor(factor float64) error {
+	if cgoDisabled {
+		return nil
+	}
+
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -373,6 +490,10 @@ func videoSetStreamQualityFactor(factor float64) error {
 }
 
 func videoGetEDID() (string, error) {
+	if cgoDisabled {
+		return "", nil
+	}
+
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -381,6 +502,10 @@ func videoGetEDID() (string, error) {
 }
 
 func videoSetEDID(edid string) error {
+	if cgoDisabled {
+		return nil
+	}
+
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 

internal/native/native.go

@@ -9,6 +9,7 @@ import (
 )
 
 type Native struct {
+	disable              bool
 	ready                chan struct{}
 	l                    *zerolog.Logger
 	lD                   *zerolog.Logger
@@ -27,6 +28,7 @@ type Native struct {
 }
 
 type NativeOptions struct {
+	Disable              bool
 	SystemVersion        *semver.Version
 	AppVersion           *semver.Version
 	DisplayRotation      uint16
@@ -74,6 +76,7 @@ func NewNative(opts NativeOptions) *Native {
 	}
 
 	return &Native{
+		disable:              opts.Disable,
 		ready:                make(chan struct{}),
 		l:                    nativeLogger,
 		lD:                   displayLogger,
@@ -92,6 +95,12 @@ func NewNative(opts NativeOptions) *Native {
 }
 
 func (n *Native) Start() {
+	if n.disable {
+		nativeLogger.Warn().Msg("native is disabled, skipping initialization")
+		setCgoDisabled(true)
+		return
+	}
+
 	// set up singleton
 	setInstance(n)
 	setUpNativeHandlers()

jsonrpc.go

@@ -1248,4 +1248,5 @@ var rpcHandlers = map[string]RPCHandler{
 	"setKeyboardMacros":      {Func: setKeyboardMacros, Params: []string{"params"}},
 	"getLocalLoopbackOnly":   {Func: rpcGetLocalLoopbackOnly},
 	"setLocalLoopbackOnly":   {Func: rpcSetLocalLoopbackOnly, Params: []string{"enabled"}},
+	"getFailSafeLogs":        {Func: rpcGetFailsafeLogs},
 }

log.go

@@ -11,6 +11,7 @@ func ErrorfL(l *zerolog.Logger, format string, err error, args ...any) error {
 
 var (
 	logger          = logging.GetSubsystemLogger("jetkvm")
+	failsafeLogger  = logging.GetSubsystemLogger("failsafe")
 	networkLogger   = logging.GetSubsystemLogger("network")
 	cloudLogger     = logging.GetSubsystemLogger("cloud")
 	websocketLogger = logging.GetSubsystemLogger("websocket")

main.go

@@ -15,6 +15,12 @@ var appCtx context.Context
 
 func Main() {
 	logger.Log().Msg("JetKVM Starting Up")
+
+	checkFailsafeReason()
+	if failsafeModeActive {
+		logger.Warn().Str("reason", failsafeModeReason).Msg("failsafe mode activated")
+	}
+
 	LoadConfig()
 
 	var cancel context.CancelFunc
@@ -50,6 +56,7 @@ func Main() {
 	// Initialize network
 	if err := initNetwork(); err != nil {
 		logger.Error().Err(err).Msg("failed to initialize network")
+		// TODO: reset config to default
 		os.Exit(1)
 	}
 
@@ -60,7 +67,6 @@ func Main() {
 	// Initialize mDNS
 	if err := initMdns(); err != nil {
 		logger.Error().Err(err).Msg("failed to initialize mDNS")
-		os.Exit(1)
 	}
 
 	initPrometheus()

native.go

@@ -17,6 +17,7 @@ var (
 
 func initNative(systemVersion *semver.Version, appVersion *semver.Version) {
 	nativeInstance = native.NewNative(native.NativeOptions{
+		Disable:              failsafeModeActive,
 		SystemVersion:        systemVersion,
 		AppVersion:           appVersion,
 		DisplayRotation:      config.GetDisplayRotation(),

ui/src/components/FailSafeModeBanner.tsx

@@ -0,0 +1,30 @@
+import { LuTriangleAlert } from "react-icons/lu";
+
+import Card from "@components/Card";
+
+interface FailsafeModeBannerProps {
+  reason: string;
+}
+
+export function FailsafeModeBanner({ reason }: FailsafeModeBannerProps) {
+  const getReasonMessage = () => {
+    switch (reason) {
+      case "video":
+        return "Failsafe Mode Active: Video-related settings are currently unavailable";
+      default:
+        return "Failsafe Mode Active: Some settings may be unavailable";
+    }
+  };
+
+  return (
+    <Card>
+      <div className="diagonal-stripes flex items-center gap-3 p-4 rounded">
+          <LuTriangleAlert className="h-5 w-5 flex-shrink-0 text-red-600 dark:text-red-400" />
+          <p className="text-sm font-medium text-red-800 dark:text-white">
+            {getReasonMessage()}
+          </p>
+      </div>
+    </Card>
+  );
+}
+

ui/src/components/FailSafeModeOverlay.tsx

@@ -0,0 +1,216 @@
+import { useState } from "react";
+import { ExclamationTriangleIcon } from "@heroicons/react/24/solid";
+import { motion, AnimatePresence } from "framer-motion";
+import { LuInfo } from "react-icons/lu";
+
+import { Button } from "@/components/Button";
+import Card, { GridCard } from "@components/Card";
+import { JsonRpcResponse, useJsonRpc } from "@/hooks/useJsonRpc";
+import { useDeviceUiNavigation } from "@/hooks/useAppNavigation";
+import { useVersion } from "@/hooks/useVersion";
+import { useDeviceStore } from "@/hooks/stores";
+import notifications from "@/notifications";
+import { DOWNGRADE_VERSION } from "@/ui.config";
+
+import { GitHubIcon } from "./Icons";
+
+
+
+interface FailSafeModeOverlayProps {
+  reason: string;
+}
+
+interface OverlayContentProps {
+  readonly children: React.ReactNode;
+}
+
+function OverlayContent({ children }: OverlayContentProps) {
+  return (
+    <GridCard cardClassName="h-full pointer-events-auto outline-hidden!">
+      <div className="flex h-full w-full flex-col items-center justify-center rounded-md border border-slate-800/30 dark:border-slate-300/20">
+        {children}
+      </div>
+    </GridCard>
+  );
+}
+
+interface TooltipProps {
+  readonly children: React.ReactNode;
+  readonly text: string;
+  readonly show: boolean;
+}
+
+function Tooltip({ children, text, show }: TooltipProps) {
+  if (!show) {
+    return <>{children}</>;
+  }
+
+
+  return (
+    <div className="group/tooltip relative">
+      {children}
+      <div className="pointer-events-none absolute bottom-full left-1/2 mb-2 hidden -translate-x-1/2 opacity-0 transition-opacity group-hover/tooltip:block group-hover/tooltip:opacity-100">
+        <Card>
+          <div className="whitespace-nowrap px-2 py-1 text-xs flex items-center gap-1 justify-center">
+            <LuInfo className="h-3 w-3 text-slate-700 dark:text-slate-300" />
+            {text}
+          </div>
+        </Card>
+      </div>
+    </div>
+  );
+}
+
+export function FailSafeModeOverlay({ reason }: FailSafeModeOverlayProps) {
+  const { send } = useJsonRpc();
+  const { navigateTo } = useDeviceUiNavigation();
+  const { appVersion } = useVersion();
+  const { systemVersion } = useDeviceStore();
+  const [isDownloadingLogs, setIsDownloadingLogs] = useState(false);
+  const [hasDownloadedLogs, setHasDownloadedLogs] = useState(false);
+
+  const getReasonCopy = () => {
+    switch (reason) {
+      case "video":
+        return {
+          message:
+            "We've detected an issue with the video capture process. Your device is still running and accessible, but video streaming is temporarily unavailable.",
+        };
+      default:
+        return {
+          message:
+            "A critical process has encountered an issue. Your device is still accessible, but some functionality may be temporarily unavailable.",
+        };
+    }
+  };
+
+  const { message } = getReasonCopy();
+
+  const handleReportAndDownloadLogs = () => {
+    setIsDownloadingLogs(true);
+
+    send("getFailSafeLogs", {}, async (resp: JsonRpcResponse) => {
+      setIsDownloadingLogs(false);
+
+      if ("error" in resp) {
+        notifications.error(`Failed to get recovery logs: ${resp.error.message}`);
+        return;
+      }
+
+      // Download logs
+      const logContent = resp.result as string;
+      const timestamp = new Date().toISOString().replace(/[:.]/g, "-");
+      const filename = `jetkvm-recovery-${reason}-${timestamp}.txt`;
+
+      const blob = new Blob([logContent], { type: "text/plain" });
+      const url = URL.createObjectURL(blob);
+      const a = document.createElement("a");
+      a.href = url;
+      a.download = filename;
+      document.body.appendChild(a);
+      await new Promise(resolve => setTimeout(resolve, 1000));
+      a.click();
+      await new Promise(resolve => setTimeout(resolve, 1000));
+      document.body.removeChild(a);
+      URL.revokeObjectURL(url);
+
+      notifications.success("Crash logs downloaded successfully");
+      setHasDownloadedLogs(true);
+
+      // Open GitHub issue
+      const issueBody = `## Issue Description
+The \`${reason}\` process encountered an error and failsafe mode was activated.
+
+**Reason:** \`${reason}\`
+**Timestamp:** ${new Date().toISOString()}
+**App Version:** ${appVersion || "Unknown"}
+**System Version:** ${systemVersion || "Unknown"}
+
+## Logs
+Please attach the recovery logs file that was downloaded to your computer:
+\`${filename}\`
+
+> [!NOTE]
+> Please remove any sensitive information from the logs. The reports are public and can be viewed by anyone.
+
+## Additional Context
+[Please describe what you were doing when this occurred]`;
+
+      const issueUrl =
+        `https://github.com/jetkvm/kvm/issues/new?` +
+        `title=${encodeURIComponent(`Recovery Mode: ${reason} process issue`)}&` +
+        `body=${encodeURIComponent(issueBody)}`;
+
+      window.open(issueUrl, "_blank");
+    });
+  };
+
+  const handleDowngrade = () => {
+    navigateTo(`/settings/general/update?app=${DOWNGRADE_VERSION}`);
+  };
+
+  return (
+    <AnimatePresence>
+      <motion.div
+        className="aspect-video h-full w-full isolate"
+        initial={{ opacity: 0 }}
+        animate={{ opacity: 1 }}
+        exit={{ opacity: 0, transition: { duration: 0 } }}
+        transition={{
+          duration: 0.4,
+          ease: "easeInOut",
+        }}
+      >
+        <OverlayContent>
+          <div className="flex max-w-lg flex-col items-start gap-y-1">
+            <ExclamationTriangleIcon className="h-12 w-12 text-yellow-500" />
+            <div className="text-left text-sm text-slate-700 dark:text-slate-300">
+              <div className="space-y-4">
+                <div className="space-y-2 text-black dark:text-white">
+                  <h2 className="text-xl font-bold">Fail safe mode activated</h2>
+                  <p className="text-sm">{message}</p>
+                </div>
+                <div className="space-y-3">
+                  <div className="flex flex-wrap items-center gap-2">
+                    <Button
+                      onClick={handleReportAndDownloadLogs}
+                      theme="primary"
+                      size="SM"
+                      disabled={isDownloadingLogs}
+                      LeadingIcon={GitHubIcon}
+                      text={isDownloadingLogs ? "Downloading Logs..." : "Download Logs & Report Issue"}
+                    />
+
+                    <div className="h-8 w-px bg-slate-200 dark:bg-slate-700 block" />
+                    <Tooltip text="Download logs first" show={!hasDownloadedLogs}>
+                      <Button
+                        onClick={() => navigateTo("/settings/general/reboot")}
+                        theme="light"
+                        size="SM"
+                        text="Reboot Device"
+                        disabled={!hasDownloadedLogs}
+                      />
+                    </Tooltip>
+
+                    <Tooltip text="Download logs first" show={!hasDownloadedLogs}>
+                      <Button
+                        size="SM"
+                        onClick={handleDowngrade}
+                        theme="light"
+                        text={`Downgrade to v${DOWNGRADE_VERSION}`}
+                        disabled={!hasDownloadedLogs}
+                      />
+                    </Tooltip>
+                  </div>
+
+
+                </div>
+              </div>
+            </div>
+          </div>
+        </OverlayContent>
+      </motion.div>
+    </AnimatePresence>
+  );
+}
+

ui/src/hooks/stores.ts

@@ -1003,3 +1003,15 @@ export const useMacrosStore = create<MacrosState>((set, get) => ({
     }
   },
 }));
+
+export interface FailsafeModeState {
+  isFailsafeMode: boolean;
+  reason: string; // "video", "network", etc.
+  setFailsafeMode: (active: boolean, reason: string) => void;
+}
+
+export const useFailsafeModeStore = create<FailsafeModeState>(set => ({
+  isFailsafeMode: false,
+  reason: "",
+  setFailsafeMode: (active, reason) => set({ isFailsafeMode: active, reason }),
+}));

ui/src/hooks/useJsonRpc.ts

@@ -1,6 +1,6 @@
 import { useCallback, useEffect } from "react";
 
-import { useRTCStore } from "@hooks/stores";
+import { useRTCStore, useFailsafeModeStore } from "@hooks/stores";
 
 export interface JsonRpcRequest {
   jsonrpc: string;
@@ -34,12 +34,51 @@ export const RpcMethodNotFound = -32601;
 const callbackStore = new Map<number | string, (resp: JsonRpcResponse) => void>();
 let requestCounter = 0;
 
+// Map of blocked RPC methods by failsafe reason
+const blockedMethodsByReason: Record<string, string[]> = {
+  video: [
+    'setStreamQualityFactor',
+    'getEDID',
+    'setEDID',
+    'getVideoLogStatus',
+    'setDisplayRotation',
+    'getVideoSleepMode',
+    'setVideoSleepMode',
+    'getVideoState',
+  ],
+};
+
 export function useJsonRpc(onRequest?: (payload: JsonRpcRequest) => void) {
   const { rpcDataChannel } = useRTCStore();
+  const { isFailsafeMode, reason } = useFailsafeModeStore();
 
   const send = useCallback(
     async (method: string, params: unknown, callback?: (resp: JsonRpcResponse) => void) => {
       if (rpcDataChannel?.readyState !== "open") return;
+
+      // Check if method is blocked in failsafe mode
+      if (isFailsafeMode && reason) {
+        const blockedMethods = blockedMethodsByReason[reason] || [];
+        if (blockedMethods.includes(method)) {
+          console.warn(`RPC method "${method}" is blocked in failsafe mode (reason: ${reason})`);
+
+          // Call callback with error if provided
+          if (callback) {
+            const errorResponse: JsonRpcErrorResponse = {
+              jsonrpc: "2.0",
+              error: {
+                code: -32000,
+                message: "Method unavailable in failsafe mode",
+                data: `This feature is unavailable while in failsafe mode (${reason})`,
+              },
+              id: requestCounter + 1,
+            };
+            callback(errorResponse);
+          }
+          return;
+        }
+      }
+
       requestCounter++;
       const payload = { jsonrpc: "2.0", method, params, id: requestCounter };
       // Store the callback if it exists
@@ -47,7 +86,7 @@ export function useJsonRpc(onRequest?: (payload: JsonRpcRequest) => void) {
 
       rpcDataChannel.send(JSON.stringify(payload));
     },
-    [rpcDataChannel]
+    [rpcDataChannel, isFailsafeMode, reason]
   );
 
   useEffect(() => {

ui/src/index.css

@@ -363,3 +363,11 @@ video::-webkit-media-controls {
 .hide-scrollbar::-webkit-scrollbar {
   display: none;
 }
+
+.diagonal-stripes {
+  background: repeating-linear-gradient(
+    135deg,
+    rgba(255, 0, 0, 0.1) 0 12px, /* red-50 with 20% opacity */
+    transparent 12px 24px
+  );
+}

ui/src/routes/devices.$id.settings.general.reboot.tsx

@@ -1,14 +1,24 @@
-import { useCallback } from "react";
+import { useCallback , useState } from "react";
 import { useNavigate } from "react-router";
 
 import { useJsonRpc } from "@hooks/useJsonRpc";
 import { Button } from "@components/Button";
-import { m } from "@localizations/messages.js";
+import { useFailsafeModeStore } from "@/hooks/stores";
 import { sleep } from "@/utils";
+import { m } from "@localizations/messages.js";
+
+import LoadingSpinner from "../components/LoadingSpinner";
+import { useDeviceUiNavigation } from "../hooks/useAppNavigation";
+
+// Time to wait after initiating reboot before redirecting to home
+const REBOOT_REDIRECT_DELAY_MS = 5000;
 
 export default function SettingsGeneralRebootRoute() {
   const navigate = useNavigate();
   const { send } = useJsonRpc();
+  const [isRebooting, setIsRebooting] = useState(false);
+  const { navigateTo } = useDeviceUiNavigation();
+  const { setFailsafeMode } = useFailsafeModeStore();
   
   const onClose = useCallback(async () => {
     navigate(".."); // back to the devices.$id.settings page
@@ -18,17 +28,24 @@ export default function SettingsGeneralRebootRoute() {
   }, [navigate]);
 
 
-  const onConfirmUpdate = useCallback(() => {
+  const onConfirmUpdate = useCallback(async () => {
+    setIsRebooting(true);
     send("reboot", {  force: true });
-  }, [send]);
 
-  return <Dialog onClose={onClose} onConfirmUpdate={onConfirmUpdate} />;
+    await new Promise(resolve => setTimeout(resolve, REBOOT_REDIRECT_DELAY_MS));
+    setFailsafeMode(false, "");
+    navigateTo("/");
+  }, [navigateTo, send, setFailsafeMode]);
+
+  return <Dialog isRebooting={isRebooting} onClose={onClose} onConfirmUpdate={onConfirmUpdate} />;
 }
 
 export function Dialog({
+  isRebooting,
   onClose,
   onConfirmUpdate,
 }: Readonly<{
+  isRebooting: boolean;
   onClose: () => void;
   onConfirmUpdate: () => void;
 }>) {
@@ -37,6 +54,7 @@ export function Dialog({
     <div className="pointer-events-auto relative mx-auto text-left">
       <div>
         <ConfirmationBox
+          isRebooting={isRebooting}
           onYes={onConfirmUpdate}
           onNo={onClose}
         />
@@ -46,9 +64,11 @@ export function Dialog({
 }
 
 function ConfirmationBox({
+  isRebooting,
   onYes,
   onNo,
 }: {
+  isRebooting: boolean;
   onYes: () => void;
   onNo: () => void;
 }) {
@@ -61,11 +81,16 @@ function ConfirmationBox({
         <p className="text-sm text-slate-600 dark:text-slate-300">
           {m.general_reboot_description()}
         </p>
-
+        {isRebooting ? (
+          <div className="mt-4 flex items-center justify-center">
+            <LoadingSpinner className="h-6 w-6 text-blue-700 dark:text-blue-500" />
+          </div>
+        ) : (
           <div className="mt-4 flex gap-x-2">
             <Button size="SM" theme="light" text={m.general_reboot_yes_button()} onClick={onYes} />
             <Button size="SM" theme="blank" text={m.general_reboot_no_button()} onClick={onNo} />
           </div>
+        )}
       </div>
     </div>
   );

ui/src/routes/devices.$id.settings.tsx

@@ -20,7 +20,8 @@ import { useUiStore } from "@hooks/stores";
 import Card from "@components/Card";
 import { LinkButton } from "@components/Button";
 import { FeatureFlag } from "@components/FeatureFlag";
-import { m } from "@localizations/messages.js";
+import { m, useFailsafeModeStore } from "@localizations/messages.js";
+import { FailsafeModeBanner } from "@components/FailSafeModeBanner";
 
 /* TODO: Migrate to using URLs instead of the global state. To simplify the refactoring, we'll keep the global state for now. */
 export default function SettingsRoute() {
@@ -30,6 +31,8 @@ export default function SettingsRoute() {
   const [showLeftGradient, setShowLeftGradient] = useState(false);
   const [showRightGradient, setShowRightGradient] = useState(false);
   const { width = 0 } = useResizeObserver({ ref: scrollContainerRef as React.RefObject<HTMLDivElement> });
+  const { isFailsafeMode: isFailsafeMode, reason: failsafeReason } = useFailsafeModeStore();
+  const isVideoDisabled = isFailsafeMode && failsafeReason === "video";
 
   // Handle scroll position to show/hide gradients
   const handleScroll = () => {
@@ -158,21 +161,28 @@ export default function SettingsRoute() {
                     </NavLink>
                   </div>
                 </FeatureFlag>
-                <div className="shrink-0">
+                <div className={cx("shrink-0", {
+                  "opacity-50 cursor-not-allowed": isVideoDisabled
+                })}>
                   <NavLink
                     to="video"
-                    className={({ isActive }) => (isActive ? "active" : "")}
+                    className={({ isActive }) => cx(isActive ? "active" : "", {
-                  >
+                      "pointer-events-none": isVideoDisabled
+                    })}                  >
                     <div className="flex items-center gap-x-2 rounded-md px-2.5 py-2.5 text-sm transition-colors hover:bg-slate-100 dark:hover:bg-slate-700 in-[.active]:bg-blue-50 in-[.active]:text-blue-700! md:in-[.active]:bg-transparent dark:in-[.active]:bg-blue-900 dark:in-[.active]:text-blue-200! dark:md:in-[.active]:bg-transparent">
                       <LuVideo className="h-4 w-4 shrink-0" />
                       <h1>{m.settings_video()}</h1>
                     </div>
                   </NavLink>
                 </div>
-                <div className="shrink-0">
+                <div className={cx("shrink-0", {
+                  "opacity-50 cursor-not-allowed": isVideoDisabled
+                })}>
                   <NavLink
                     to="hardware"
-                    className={({ isActive }) => (isActive ? "active" : "")}
+                    className={({ isActive }) => cx(isActive ? "active" : "", {
+                      "pointer-events-none": isVideoDisabled
+                    })}
                   >
                     <div className="flex items-center gap-x-2 rounded-md px-2.5 py-2.5 text-sm transition-colors hover:bg-slate-100 dark:hover:bg-slate-700 in-[.active]:bg-blue-50 in-[.active]:text-blue-700! md:in-[.active]:bg-transparent dark:in-[.active]:bg-blue-900 dark:in-[.active]:text-blue-200! dark:md:in-[.active]:bg-transparent">
                       <LuCpu className="h-4 w-4 shrink-0" />
@@ -238,8 +248,8 @@ export default function SettingsRoute() {
               </div>
             </Card>
           </div>
-          <div className="w-full md:col-span-6">
+          <div className="w-full md:col-span-6 space-y-4">
-            {/* <AutoHeight> */}
+            {isFailsafeMode && failsafeReason && <FailsafeModeBanner reason={failsafeReason} />}
             <Card className="dark:bg-slate-800">
               <div
                 className="space-y-4 px-8 py-6"

ui/src/routes/devices.$id.tsx

@@ -33,6 +33,7 @@ import {
   useUpdateStore,
   useVideoStore,
   VideoState,
+  useFailsafeModeStore,
 } from "@hooks/stores";
 import { JsonRpcRequest, JsonRpcResponse, RpcMethodNotFound, useJsonRpc } from "@hooks/useJsonRpc";
 import { useDeviceUiNavigation } from "@hooks/useAppNavigation";
@@ -43,6 +44,7 @@ const ConnectionStatsSidebar = lazy(() => import('@components/sidebar/connection
 const Terminal = lazy(() => import('@components/Terminal'));
 const UpdateInProgressStatusCard = lazy(() => import("@components/UpdateInProgressStatusCard"));
 import Modal from "@components/Modal";
+import { FailSafeModeOverlay } from "@components/FailSafeModeOverlay";
 import {
   ConnectionFailedOverlay,
   LoadingConnectionOverlay,
@@ -101,6 +103,7 @@ const loader: LoaderFunction = ({ params }: LoaderFunctionArgs) => {
   return isOnDevice ? deviceLoader() : cloudLoader(params);
 };
 
+
 export default function KvmIdRoute() {
   const loaderResp = useLoaderData();
   // Depending on the mode, we set the appropriate variables
@@ -619,7 +622,8 @@ export default function KvmIdRoute() {
     keysDownState, setKeysDownState,
     setUsbState,
   } = useHidStore();
-  const { setHidRpcDisabled } = useRTCStore();
+  const setHidRpcDisabled = useRTCStore(state => state.setHidRpcDisabled);
+  const { setFailsafeMode } = useFailsafeModeStore();
 
   const [hasUpdated, setHasUpdated] = useState(false);
   const { navigateTo } = useDeviceUiNavigation();
@@ -696,6 +700,12 @@ export default function KvmIdRoute() {
       setRebootState({ isRebooting: true, postRebootAction });
       navigateTo("/");
     }
+
+    if (resp.method === "failsafeMode") {
+      const { active, reason } = resp.params as { active: boolean; reason: string };
+      console.debug("Setting failsafe mode", { active, reason });
+      setFailsafeMode(active, reason);
+    }
   }
 
   const { send } = useJsonRpc(onJsonRpcRequest);
@@ -794,6 +804,8 @@ export default function KvmIdRoute() {
     getLocalVersion();
   }, [appVersion, getLocalVersion]);
 
+  const { isFailsafeMode, reason: failsafeReason } = useFailsafeModeStore();
+
   const ConnectionStatusElement = useMemo(() => {
     const isOtherSession = location.pathname.includes("other-session");
     if (isOtherSession) return null;
@@ -869,13 +881,15 @@ export default function KvmIdRoute() {
           />
 
           <div className="relative flex h-full w-full overflow-hidden">
-            <WebRTCVideo hasConnectionIssues={!!ConnectionStatusElement} />
+            {(isFailsafeMode && failsafeReason === "video") ? null : <WebRTCVideo hasConnectionIssues={!!ConnectionStatusElement} />}
             <div
               style={{ animationDuration: "500ms" }}
               className="animate-slideUpFade pointer-events-none absolute inset-0 flex items-center justify-center p-4"
             >
               <div className="relative h-full max-h-[720px] w-full max-w-[1280px] rounded-md">
-                {!!ConnectionStatusElement && ConnectionStatusElement}
+                {isFailsafeMode && failsafeReason ? (
+                  <FailSafeModeOverlay reason={failsafeReason} />
+                ) : !!ConnectionStatusElement && ConnectionStatusElement}
               </div>
             </div>
             <SidebarContainer sidebarView={sidebarView} />

ui/src/ui.config.ts

@@ -1,4 +1,6 @@
 export const CLOUD_API = import.meta.env.VITE_CLOUD_API;
 
+export const DOWNGRADE_VERSION = import.meta.env.VITE_DOWNGRADE_VERSION || "0.4.8";
+
 // In device mode, an empty string uses the current hostname (the JetKVM device's IP) as the API endpoint
 export const DEVICE_API = "";

video.go

@@ -27,6 +27,7 @@ func triggerVideoStateUpdate() {
 }
 
 func rpcGetVideoState() (native.VideoState, error) {
+	notifyFailsafeMode(currentSession)
 	return lastVideoState, nil
 }
 

webrtc.go

@@ -289,6 +289,7 @@ func newSession(config SessionConfig) (*Session, error) {
 			triggerOTAStateUpdate()
 			triggerVideoStateUpdate()
 			triggerUSBStateUpdate()
+			notifyFailsafeMode(session)
 		case "terminal":
 			handleTerminalChannel(d)
 		case "serial":
@@ -391,10 +392,12 @@ func newSession(config SessionConfig) (*Session, error) {
 }
 
 func onActiveSessionsChanged() {
+	notifyFailsafeMode(currentSession)
 	requestDisplayUpdate(true, "active_sessions_changed")
 }
 
 func onFirstSessionConnected() {
+	notifyFailsafeMode(currentSession)
 	_ = nativeInstance.VideoStart()
 	stopVideoSleepModeTicker()
 }