From 6b8752b4293d811c8b6a3d04428f79ab11084e33 Mon Sep 17 00:00:00 2001
From: keshav9926 <kkakani160@gmail.com>
Date: Thu, 6 Aug 2026 21:57:34 +0530
Subject: [PATCH] fix(ascend): guard nil Requests in MutateAdmission

A container declaring only limits (no requests block) reaches the
trimmed-memory write with ctr.Resources.Requests == nil and panics
(assignment to entry in nil map) in the admission webhook. Initialize
the map before writing, as kunlun vdevice already does for the same
write and as merged for mthreads in #2254.

Add Test_MutateAdmission_NilRequests covering both panicking shapes:
memory limit present without a requests block, and count-only without
a requests block.

Signed-off-by: keshav9926 <kkakani160@gmail.com>
---
 pkg/device/ascend/device.go      |  5 ++
 pkg/device/ascend/device_test.go | 80 ++++++++++++++++++++++++++++++++
 2 files changed, 85 insertions(+)

diff --git a/pkg/device/ascend/device.go b/pkg/device/ascend/device.go
index 6496d115ee..d262da89f9 100644
--- a/pkg/device/ascend/device.go
+++ b/pkg/device/ascend/device.go
@@ -178,6 +178,11 @@ func (dev *Devices) MutateAdmission(ctr *corev1.Container, p *corev1.Pod) (bool,
 			return true, errors.New("vNPU not supported for multiple devices")
 		}
 	}
+	// Requests may be nil when the pod declares only limits; writing to a
+	// nil map panics.
+	if ctr.Resources.Requests == nil {
+		ctr.Resources.Requests = corev1.ResourceList{}
+	}
 	ctr.Resources.Limits[corev1.ResourceName(dev.config.ResourceMemoryName)] = resource.MustParse(fmt.Sprint(trimMem))
 	ctr.Resources.Requests[corev1.ResourceName(dev.config.ResourceMemoryName)] = resource.MustParse(fmt.Sprint(trimMem))
 
diff --git a/pkg/device/ascend/device_test.go b/pkg/device/ascend/device_test.go
index 742b4981b3..ebdbdd032c 100644
--- a/pkg/device/ascend/device_test.go
+++ b/pkg/device/ascend/device_test.go
@@ -707,6 +707,86 @@ func Test_MutateAdmission(t *testing.T) {
 	}
 }
 
+func Test_MutateAdmission_NilRequests(t *testing.T) {
+	// Regression test: a pod that declares only limits (no requests block)
+	// must not panic when MutateAdmission writes the trimmed memory request.
+	tests := []struct {
+		name       string
+		ctr        corev1.Container
+		wantMemory string
+	}{
+		{
+			name: "memory limit set, requests block absent",
+			ctr: corev1.Container{
+				Resources: corev1.ResourceRequirements{
+					Limits: corev1.ResourceList{
+						"huawei.com/Ascend910A":        resource.MustParse("1"),
+						"huawei.com/Ascend910A-memory": resource.MustParse("8738"),
+					},
+				},
+			},
+			wantMemory: "8738",
+		},
+		{
+			name: "count only, no memory limit, requests block absent",
+			ctr: corev1.Container{
+				Resources: corev1.ResourceRequirements{
+					Limits: corev1.ResourceList{
+						"huawei.com/Ascend910A": resource.MustParse("1"),
+					},
+				},
+			},
+			wantMemory: "32768", // defaults to whole-card MemoryAllocatable
+		},
+	}
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			dev := Devices{
+				config: VNPUConfig{
+					ResourceName:       "huawei.com/Ascend910A",
+					ResourceMemoryName: "huawei.com/Ascend910A-memory",
+					MemoryAllocatable:  int64(32768),
+					MemoryCapacity:     int64(32768),
+					Templates: []Template{
+						{
+							Name:   "vir02",
+							Memory: int64(2184),
+							AICore: int32(2),
+						}, {
+							Name:   "vir04",
+							Memory: int64(4369),
+							AICore: int32(4),
+						}, {
+							Name:   "vir08",
+							Memory: int64(8738),
+							AICore: int32(8),
+						}, {
+							Name:   "vir16",
+							Memory: int64(17476),
+							AICore: int32(16),
+						},
+					},
+				},
+			}
+			pod := corev1.Pod{}
+			result, err := dev.MutateAdmission(&test.ctr, &pod)
+			if err != nil {
+				t.Fatalf("exec MutateAdmission method expect no error, but got %v", err)
+			}
+			if !result {
+				t.Fatalf("exec MutateAdmission method expect return is true, but got is false")
+			}
+			got, ok := test.ctr.Resources.Requests[corev1.ResourceName("huawei.com/Ascend910A-memory")]
+			if !ok {
+				t.Fatalf("expect memory request to be set, but it is absent")
+			}
+			if got.String() != test.wantMemory {
+				t.Fatalf("expect memory request %s, but got %s", test.wantMemory, got.String())
+			}
+		})
+	}
+}
+
 func Test_MutateAdmission910C(t *testing.T) {
 	tests := []struct {
 		name   string