Refactor installation and runner scripts for enhanced usability and security

- Updated the installation script to clarify that production wrappers do not include fixed test secrets, improving user guidance for local testing.
- Modified the jiggablend-manager and jiggablend-runner scripts to remove fixed test configurations, emphasizing the use of local test credentials via `make init-test`.
- Enhanced error handling in the runner script to ensure that an API key is provided, improving security and user feedback.
- Added new flags and options for the runner, including sandboxing capabilities and GPU ray tracing control, enhancing flexibility for users.
- Improved README documentation to reflect changes in usage and configuration, ensuring users have clear instructions for setup and execution.

internal/runner/tasks/encode.go

@@ -246,6 +246,8 @@ func (p *EncodeProcessor) Process(ctx *Context) error {
 		TwoPass:      true,
 	})
 	if err := pass1Cmd.Run(); err != nil {
+		// Pass 1 is analysis-only (writes to /dev/null). FFmpeg often exits non-zero
+		// on benign codec/option warnings while still producing passlogfile stats.
 		ctx.Warn(fmt.Sprintf("Pass 1 completed (warnings expected): %v", err))
 	}
 

internal/runner/tasks/exr_merge.go

@@ -0,0 +1,46 @@
+package tasks
+
+import (
+	"fmt"
+	"os/exec"
+	"strings"
+)
+
+// mergeEXRFiles averages multiple linear EXR renders into one (Monte Carlo accumulation).
+func mergeEXRFiles(output string, inputs []string) error {
+	if len(inputs) == 0 {
+		return fmt.Errorf("no input EXR files to merge")
+	}
+	if len(inputs) == 1 {
+		return copyFile(inputs[0], output)
+	}
+
+	args := append([]string{}, inputs...)
+	args = append(args, "-evaluate-sequence", "mean", output)
+
+	if path, err := exec.LookPath("magick"); err == nil {
+		cmd := exec.Command(path, args...)
+		if out, err := cmd.CombinedOutput(); err != nil {
+			return fmt.Errorf("magick merge failed: %w (%s)", err, strings.TrimSpace(string(out)))
+		}
+		return nil
+	}
+
+	if path, err := exec.LookPath("convert"); err == nil {
+		cmd := exec.Command(path, args...)
+		if out, err := cmd.CombinedOutput(); err != nil {
+			return fmt.Errorf("convert merge failed: %w (%s)", err, strings.TrimSpace(string(out)))
+		}
+		return nil
+	}
+
+	return fmt.Errorf("ImageMagick (magick or convert) required to merge batched EXR renders")
+}
+
+func copyFile(src, dst string) error {
+	cmd := exec.Command("cp", "-f", src, dst)
+	if out, err := cmd.CombinedOutput(); err != nil {
+		return fmt.Errorf("copy %s to %s: %w (%s)", src, dst, err, strings.TrimSpace(string(out)))
+	}
+	return nil
+}

internal/runner/tasks/processor.go

@@ -7,6 +7,7 @@ import (
 	"jiggablend/internal/runner/api"
 	"jiggablend/internal/runner/blender"
 	"jiggablend/internal/runner/encoding"
+	"jiggablend/internal/runner/sandbox"
 	"jiggablend/internal/runner/workspace"
 	"jiggablend/pkg/executils"
 	"jiggablend/pkg/types"
@@ -41,6 +42,9 @@ type Context struct {
 
 	// GPULockedOut is set when the runner has detected a GPU error (e.g. HIP) and disables GPU for all jobs.
 	GPULockedOut bool
+	// GPULockoutArmedThisAttempt is true when this task attempt newly enabled runner GPU lockout.
+	// Failures with this set free-requeue without incrementing retry_count (expected ROCm warmup).
+	GPULockoutArmedThisAttempt bool
 	// HasAMD is true when the runner detected AMD devices at startup.
 	HasAMD bool
 	// HasNVIDIA is true when the runner detected NVIDIA GPUs at startup.
@@ -53,6 +57,12 @@ type Context struct {
 	OnGPUError func()
 	// ForceCPURendering is a runner-level override that forces CPU rendering for all jobs.
 	ForceCPURendering bool
+	// DisableRT disables GPU ray tracing acceleration (runner-level flag).
+	DisableRT bool
+	// HipGPUSampleBatch limits samples per GPU render pass on gfx115x (0 = no batching).
+	HipGPUSampleBatch int
+	// Sandbox wraps Blender execution (none/podman). Nil means none.
+	Sandbox sandbox.Wrapper
 }
 
 // ErrJobCancelled indicates the manager-side job was cancelled during execution.
@@ -80,7 +90,10 @@ func NewContext(
 	hasIntel bool,
 	gpuDetectionFailed bool,
 	forceCPURendering bool,
+	disableRT bool,
+	hipGPUSampleBatch int,
 	onGPUError func(),
+	sb sandbox.Wrapper,
 ) *Context {
 	if frameEnd < frameStart {
 		frameEnd = frameStart
@@ -107,7 +120,10 @@ func NewContext(
 		HasIntel:           hasIntel,
 		GPUDetectionFailed: gpuDetectionFailed,
 		ForceCPURendering:  forceCPURendering,
-		OnGPUError:         onGPUError,
+		DisableRT:           disableRT,
+		HipGPUSampleBatch:   hipGPUSampleBatch,
+		OnGPUError:          onGPUError,
+		Sandbox:             sb,
 	}
 }
 
@@ -148,18 +164,22 @@ func (c *Context) OutputUploaded(fileName string) {
 }
 
 // Complete sends task completion.
+// When the failure newly armed GPU lockout, free_requeue is set so the manager
+// requeues without burning retry_count.
 func (c *Context) Complete(success bool, errorMsg error) {
 	if c.JobConn != nil {
-		c.JobConn.Complete(c.TaskID, success, errorMsg)
+		freeRequeue := !success && c.GPULockoutArmedThisAttempt
+		c.JobConn.Complete(c.TaskID, success, errorMsg, freeRequeue)
 	}
 }
 
 // GetOutputFormat returns the output format from metadata or default.
+// Product default is EXR (Blender always renders EXR; deliverable may add video).
 func (c *Context) GetOutputFormat() string {
 	if c.Metadata != nil && c.Metadata.RenderSettings.OutputFormat != "" {
 		return c.Metadata.RenderSettings.OutputFormat
 	}
-	return "PNG"
+	return "EXR"
 }
 
 // GetFrameRate returns the frame rate from metadata or default.
@@ -183,7 +203,9 @@ func (c *Context) ShouldUnhideObjects() bool {
 	return c.Metadata != nil && c.Metadata.UnhideObjects != nil && *c.Metadata.UnhideObjects
 }
 
-// ShouldEnableExecution returns whether to enable auto-execution.
+// ShouldEnableExecution returns whether to pass Blender --enable-autoexec
+// (Python drivers/scripts inside the .blend). Job-bundled blender_addons/ install
+// independently whenever that folder is present in the context.
 func (c *Context) ShouldEnableExecution() bool {
 	return c.Metadata != nil && c.Metadata.EnableExecution != nil && *c.Metadata.EnableExecution
 }
@@ -211,6 +233,69 @@ func (c *Context) ShouldForceCPU() bool {
 	return false
 }
 
+// GetCyclesSamples returns the target Cycles sample count from metadata (default 128).
+func (c *Context) GetCyclesSamples() int {
+	if c.Metadata != nil && c.Metadata.RenderSettings.EngineSettings != nil {
+		if v, ok := c.Metadata.RenderSettings.EngineSettings["samples"]; ok {
+			switch n := v.(type) {
+			case float64:
+				if int(n) > 0 {
+					return int(n)
+				}
+			case int:
+				if n > 0 {
+					return n
+				}
+			}
+		}
+	}
+	return 128
+}
+
+// GetCyclesSeed returns the Cycles seed from metadata (default 0).
+func (c *Context) GetCyclesSeed() int {
+	if c.Metadata != nil && c.Metadata.RenderSettings.EngineSettings != nil {
+		if v, ok := c.Metadata.RenderSettings.EngineSettings["seed"]; ok {
+			switch n := v.(type) {
+			case float64:
+				return int(n)
+			case int:
+				return n
+			}
+		}
+	}
+	return 0
+}
+
+// ShouldBatchGPUSamples returns true when HIP GPU renders should be split into sample batches.
+func (c *Context) ShouldBatchGPUSamples() bool {
+	if c.ShouldForceCPU() || c.HipGPUSampleBatch <= 0 {
+		return false
+	}
+	return c.GetCyclesSamples() > c.HipGPUSampleBatch
+}
+
+// ShouldDisableRT returns true when GPU ray tracing acceleration should be disabled.
+func (c *Context) ShouldDisableRT() bool {
+	if c.DisableRT {
+		return true
+	}
+	if c.Metadata != nil && c.Metadata.RenderSettings.EngineSettings != nil {
+		settings := c.Metadata.RenderSettings.EngineSettings
+		if v, ok := settings["disable_rt"]; ok {
+			if b, ok := v.(bool); ok && b {
+				return true
+			}
+		}
+		if v, ok := settings["disable_hiprt"]; ok {
+			if b, ok := v.(bool); ok && b {
+				return true
+			}
+		}
+	}
+	return false
+}
+
 // IsJobCancelled checks whether the manager marked this job as cancelled.
 func (c *Context) IsJobCancelled() (bool, error) {
 	if c.Manager == nil {

internal/runner/tasks/processor_test.go

@@ -8,7 +8,7 @@ import (
 )
 
 func TestNewContext_NormalizesFrameEnd(t *testing.T) {
-	ctx := NewContext(1, 2, "job", 10, 1, "render", "/tmp", "tok", nil, nil, nil, nil, nil, nil, nil, false, false, false, false, false, false, nil)
+	ctx := NewContext(1, 2, "job", 10, 1, "render", "/tmp", "tok", nil, nil, nil, nil, nil, nil, nil, false, false, false, false, false, false, false, 0, nil, nil)
 	if ctx.FrameEnd != 10 {
 		t.Fatalf("expected FrameEnd to be normalized to Frame, got %d", ctx.FrameEnd)
 	}
@@ -16,8 +16,8 @@ func TestNewContext_NormalizesFrameEnd(t *testing.T) {
 
 func TestContext_GetOutputFormat_Default(t *testing.T) {
 	ctx := &Context{}
-	if got := ctx.GetOutputFormat(); got != "PNG" {
-		t.Fatalf("GetOutputFormat() = %q, want PNG", got)
+	if got := ctx.GetOutputFormat(); got != "EXR" {
+		t.Fatalf("GetOutputFormat() = %q, want EXR", got)
 	}
 }
 

internal/runner/tasks/render.go

@@ -12,6 +12,7 @@ import (
 	"strings"
 
 	"jiggablend/internal/runner/blender"
+	"jiggablend/internal/runner/sandbox"
 	"jiggablend/internal/runner/workspace"
 	"jiggablend/pkg/scripts"
 	"jiggablend/pkg/types"
@@ -28,6 +29,8 @@ func NewRenderProcessor() *RenderProcessor {
 // gpuErrorSubstrings are log line substrings that indicate a GPU backend error (matched case-insensitively); any match triggers full GPU lockout.
 var gpuErrorSubstrings = []string{
 	"illegal address in hip", // HIP (AMD) e.g. "Illegal address in HIP" or "Illegal address in hip"
+	"memory access fault",    // AMDGPU page fault during HIP/HIPRT (not necessarily OOM)
+	"page not present",       // AMDGPU GCVM page fault detail
 	"hiperror",               // hipError* codes
 	"hip error",
 	"cuda error",
@@ -38,14 +41,18 @@ var gpuErrorSubstrings = []string{
 }
 
 // checkGPUErrorLine checks a log line for GPU error indicators and triggers runner GPU lockout if found.
+// Once lockout is already active for this attempt (or was active at context creation), further
+// matching lines are ignored so we do not spam lockout callbacks/logs on multi-line fault dumps.
 func (p *RenderProcessor) checkGPUErrorLine(ctx *Context, line string) {
+	if ctx.GPULockedOut || ctx.GPULockoutArmedThisAttempt {
+		return
+	}
 	lower := strings.ToLower(line)
 	for _, sub := range gpuErrorSubstrings {
 		if strings.Contains(lower, sub) {
 			if ctx.OnGPUError != nil {
 				ctx.OnGPUError()
 			}
-			ctx.Warn(fmt.Sprintf("GPU error detected in log (%q); GPU disabled for subsequent jobs", sub))
 			return
 		}
 	}
@@ -73,26 +80,24 @@ func (p *RenderProcessor) Process(ctx *Context) error {
 		return fmt.Errorf("failed to find blend file: %w", err)
 	}
 
-	// Get Blender binary
-	blenderBinary := "blender"
-	if version := ctx.GetBlenderVersion(); version != "" {
-		ctx.Info(fmt.Sprintf("Job requires Blender %s", version))
-		binaryPath, err := ctx.Blender.GetBinaryPath(version)
-		if err != nil {
-			ctx.Warn(fmt.Sprintf("Could not get Blender %s, using system blender: %v", version, err))
-		} else {
-			blenderBinary = binaryPath
-			ctx.Info(fmt.Sprintf("Using Blender binary: %s", blenderBinary))
-		}
-	} else {
-		ctx.Info("No Blender version specified, using system blender")
+	// Runners must use manager-provided Blender versions; never fall back to system blender.
+	version := ctx.GetBlenderVersion()
+	if version == "" {
+		return fmt.Errorf("job metadata missing blender_version: runner cannot use system blender")
 	}
 
-	blenderBinary, err = blender.ResolveBinaryPath(blenderBinary)
+	ctx.Info(fmt.Sprintf("Job requires Blender %s", version))
+	binaryPath, err := ctx.Blender.GetBinaryPath(version)
 	if err != nil {
-		return fmt.Errorf("failed to resolve blender binary: %w", err)
+		return fmt.Errorf("failed to get Blender %s from manager: %w", version, err)
 	}
 
+	blenderBinary, err := blender.ResolveBinaryPath(binaryPath)
+	if err != nil {
+		return fmt.Errorf("failed to resolve Blender %s binary: %w", version, err)
+	}
+	ctx.Info(fmt.Sprintf("Using Blender binary: %s", blenderBinary))
+
 	// Create output directory
 	outputDir := filepath.Join(ctx.WorkDir, "output")
 	if err := os.MkdirAll(outputDir, 0755); err != nil {
@@ -116,11 +121,15 @@ func (p *RenderProcessor) Process(ctx *Context) error {
 		} else {
 			ctx.Info("GPU lockout active: using CPU rendering only")
 		}
+	} else if ctx.ShouldDisableRT() {
+		ctx.Info("GPU ray tracing acceleration disabled for this job (--disable-rt)")
 	}
-
-	// Create render script
-	if err := p.createRenderScript(ctx, renderFormat); err != nil {
-		return err
+	if ctx.ShouldBatchGPUSamples() {
+		total := ctx.GetCyclesSamples()
+		ctx.Info(fmt.Sprintf(
+			"gfx115x HIP sample batching: rendering %d samples in passes of %d (ROCm driver limit, not system RAM)",
+			total, ctx.HipGPUSampleBatch,
+		))
 	}
 
 	// Render
@@ -129,7 +138,7 @@ func (p *RenderProcessor) Process(ctx *Context) error {
 	} else {
 		ctx.Info(fmt.Sprintf("Starting Blender render for frame %d...", ctx.Frame))
 	}
-	if err := p.runBlender(ctx, blenderBinary, blendFile, outputDir, renderFormat, blenderHome); err != nil {
+	if err := p.renderFrames(ctx, blenderBinary, blendFile, outputDir, renderFormat, blenderHome); err != nil {
 		if errors.Is(err, ErrJobCancelled) {
 			ctx.Warn("Render stopped because job was cancelled")
 			return err
@@ -152,7 +161,84 @@ func (p *RenderProcessor) Process(ctx *Context) error {
 	return nil
 }
 
-func (p *RenderProcessor) createRenderScript(ctx *Context, renderFormat string) error {
+type renderPassOptions struct {
+	samplesOverride *int
+	seedOverride    *int
+}
+
+func (p *RenderProcessor) renderFrames(ctx *Context, blenderBinary, blendFile, outputDir, renderFormat, blenderHome string) error {
+	if !ctx.ShouldBatchGPUSamples() {
+		if err := p.createRenderScript(ctx, renderFormat, nil); err != nil {
+			return err
+		}
+		return p.runBlender(ctx, blenderBinary, blendFile, outputDir, renderFormat, blenderHome)
+	}
+
+	totalSamples := ctx.GetCyclesSamples()
+	batchSize := ctx.HipGPUSampleBatch
+	baseSeed := ctx.GetCyclesSeed()
+	batchDir := filepath.Join(ctx.WorkDir, "sample_batches")
+	if err := os.MkdirAll(batchDir, 0755); err != nil {
+		return fmt.Errorf("failed to create sample batch directory: %w", err)
+	}
+
+	var batchOutputs []string
+	remaining := totalSamples
+	batchNum := 0
+	for remaining > 0 {
+		if err := ctx.CheckCancelled(); err != nil {
+			return err
+		}
+		passSamples := batchSize
+		if remaining < passSamples {
+			passSamples = remaining
+		}
+		seed := baseSeed + batchNum
+		batchNum++
+		ctx.Info(fmt.Sprintf("GPU sample batch %d: %d samples (seed %d, %d remaining)", batchNum, passSamples, seed, remaining-passSamples))
+
+		passOutput := filepath.Join(batchDir, fmt.Sprintf("batch_%03d", batchNum))
+		if err := os.MkdirAll(passOutput, 0755); err != nil {
+			return err
+		}
+		opts := &renderPassOptions{
+			samplesOverride: &passSamples,
+			seedOverride:    &seed,
+		}
+		if err := p.createRenderScript(ctx, renderFormat, opts); err != nil {
+			return err
+		}
+		if err := p.runBlender(ctx, blenderBinary, blendFile, passOutput, renderFormat, blenderHome); err != nil {
+			return err
+		}
+		if err := p.verifyOutputRange(ctx, passOutput, renderFormat); err != nil {
+			return err
+		}
+		batchOutputs = append(batchOutputs, p.firstFrameOutputPath(ctx, passOutput, renderFormat))
+		remaining -= passSamples
+	}
+
+	if err := os.MkdirAll(outputDir, 0755); err != nil {
+		return err
+	}
+	finalOutput := p.firstFrameOutputPath(ctx, outputDir, renderFormat)
+	ctx.Info(fmt.Sprintf("Merging %d GPU sample batches into final EXR...", len(batchOutputs)))
+	if err := mergeEXRFiles(finalOutput, batchOutputs); err != nil {
+		return err
+	}
+	ctx.Info("GPU sample batch merge completed")
+	return nil
+}
+
+func (p *RenderProcessor) firstFrameOutputPath(ctx *Context, outputDir, renderFormat string) string {
+	ext := strings.ToLower(renderFormat)
+	if ctx.FrameEnd > ctx.Frame {
+		return filepath.Join(outputDir, fmt.Sprintf("frame_%04d.%s", ctx.Frame, ext))
+	}
+	return filepath.Join(outputDir, fmt.Sprintf("frame_%04d.%s", ctx.Frame, ext))
+}
+
+func (p *RenderProcessor) createRenderScript(ctx *Context, renderFormat string, opts *renderPassOptions) error {
 	formatFilePath := filepath.Join(ctx.WorkDir, "output_format.txt")
 	renderSettingsFilePath := filepath.Join(ctx.WorkDir, "render_settings.json")
 
@@ -162,7 +248,9 @@ func (p *RenderProcessor) createRenderScript(ctx *Context, renderFormat string)
 		unhideCode = scripts.UnhideObjects
 	}
 
-	// Load template and replace placeholders
+	// Load template and replace placeholders.
+	// Job-bundled blender_addons/ always auto-install when present (users ship addons with scenes).
+	// enable_execution only controls Blender --enable-autoexec (scripts inside .blend).
 	scriptContent := scripts.RenderBlenderTemplate
 	scriptContent = strings.ReplaceAll(scriptContent, "{{UNHIDE_CODE}}", unhideCode)
 	scriptContent = strings.ReplaceAll(scriptContent, "{{FORMAT_FILE_PATH}}", fmt.Sprintf("%q", formatFilePath))
@@ -195,6 +283,20 @@ func (p *RenderProcessor) createRenderScript(ctx *Context, renderFormat string)
 		settingsMap = make(map[string]interface{})
 	}
 	settingsMap["force_cpu"] = ctx.ShouldForceCPU()
+	settingsMap["disable_rt"] = ctx.ShouldDisableRT()
+	if ctx.ShouldBatchGPUSamples() {
+		// gfx115x: large tiles trigger AMDGPU page faults during HIP renders.
+		settingsMap["tile_size_override"] = 256
+		settingsMap["use_auto_tile_override"] = true
+	}
+	if opts != nil {
+		if opts.samplesOverride != nil {
+			settingsMap["samples_override"] = *opts.samplesOverride
+		}
+		if opts.seedOverride != nil {
+			settingsMap["seed_override"] = *opts.seedOverride
+		}
+	}
 	settingsJSON, err := json.Marshal(settingsMap)
 	if err == nil {
 		if err := os.WriteFile(renderSettingsFilePath, settingsJSON, 0644); err != nil {
@@ -205,6 +307,32 @@ func (p *RenderProcessor) createRenderScript(ctx *Context, renderFormat string)
 	return nil
 }
 
+// wrapBlenderCmd builds the Blender *exec.Cmd, optionally through the sandbox wrapper.
+func wrapBlenderCmd(ctx *Context, blenderBinary string, args, env []string, blenderHome string) (*exec.Cmd, error) {
+	sb := ctx.Sandbox
+	if sb == nil {
+		var err error
+		sb, err = sandbox.New(sandbox.Options{Backend: sandbox.BackendNone})
+		if err != nil {
+			return nil, err
+		}
+	}
+	if sb.Name() != sandbox.BackendNone {
+		ctx.Info(fmt.Sprintf("Running Blender under sandbox backend %q", sb.Name()))
+	}
+	return sb.Wrap(sandbox.Spec{
+		BlenderBinary: blenderBinary,
+		Args:          args,
+		WorkDir:       ctx.WorkDir,
+		HomeDir:       blenderHome,
+		Env:           env,
+		HasAMD:        ctx.HasAMD,
+		HasNVIDIA:     ctx.HasNVIDIA,
+		HasIntel:      ctx.HasIntel,
+		ForceCPU:      ctx.ShouldForceCPU(),
+	})
+}
+
 func (p *RenderProcessor) runBlender(ctx *Context, blenderBinary, blendFile, outputDir, renderFormat, blenderHome string) error {
 	scriptPath := filepath.Join(ctx.WorkDir, "enable_gpu.py")
 	blendFileAbs, err := filepath.Abs(blendFile)
@@ -233,9 +361,6 @@ func (p *RenderProcessor) runBlender(ctx *Context, blenderBinary, blendFile, out
 		args = append(args, "-f", fmt.Sprintf("%d", ctx.Frame))
 	}
 
-	cmd := execCommand(blenderBinary, args...)
-	cmd.Dir = ctx.WorkDir
-
 	// Set up environment: LD_LIBRARY_PATH for tarball Blender, then custom HOME
 	env := os.Environ()
 	env = blender.TarballEnv(blenderBinary, env)
@@ -246,7 +371,11 @@ func (p *RenderProcessor) runBlender(ctx *Context, blenderBinary, blendFile, out
 		}
 	}
 	newEnv = append(newEnv, fmt.Sprintf("HOME=%s", blenderHome))
-	cmd.Env = newEnv
+
+	cmd, err := wrapBlenderCmd(ctx, blenderBinary, args, newEnv, blenderHome)
+	if err != nil {
+		return fmt.Errorf("failed to build sandboxed blender command: %w", err)
+	}
 
 	// Set up pipes
 	stdoutPipe, err := cmd.StdoutPipe()

internal/runner/tasks/render_test.go

@@ -4,13 +4,42 @@ import "testing"
 
 func TestCheckGPUErrorLine_TriggersCallback(t *testing.T) {
 	p := NewRenderProcessor()
-	triggered := false
+	triggered := 0
 	ctx := &Context{
-		OnGPUError: func() { triggered = true },
+		OnGPUError: func() {
+			triggered++
+			// Simulate runner arming lockout for this attempt.
+		},
 	}
 	p.checkGPUErrorLine(ctx, "Fatal: Illegal address in HIP kernel execution")
-	if !triggered {
-		t.Fatal("expected GPU error callback to be triggered")
+	if triggered != 1 {
+		t.Fatalf("expected GPU error callback once, got %d", triggered)
+	}
+	// After arming, further fault lines must not re-fire (spam protection).
+	ctx.GPULockoutArmedThisAttempt = true
+	p.checkGPUErrorLine(ctx, "page not present in GPU memory")
+	if triggered != 1 {
+		t.Fatalf("expected no further callbacks after arm, got %d", triggered)
+	}
+}
+
+func TestCheckGPUErrorLine_SkipsWhenAlreadyLockedOut(t *testing.T) {
+	p := NewRenderProcessor()
+	triggered := false
+	ctx := &Context{
+		GPULockedOut: true,
+		OnGPUError:   func() { triggered = true },
+	}
+	p.checkGPUErrorLine(ctx, "Illegal address in HIP")
+	if triggered {
+		t.Fatal("did not expect callback when GPU already locked out")
+	}
+}
+
+func TestGetBlenderVersion_EmptyWhenMissing(t *testing.T) {
+	ctx := &Context{}
+	if got := ctx.GetBlenderVersion(); got != "" {
+		t.Fatalf("expected empty blender version, got %q", got)
 	}
 }