From c71eee34774b3544120cbac946d4b605f9b93e2f Mon Sep 17 00:00:00 2001
From: Puranjay Mohan <puranjay@kernel.org>
Date: Tue, 23 Dec 2025 15:08:06 -0800
Subject: [PATCH] run-vmtest: Allow specifying cpu and memory for vms

The max-cpu parameter is currently unused by the script and therefore
vmtest defaults to 2 CPU. There is not parameter available to specify
the amount of memory to give to the vm, for this the vmtest defaults to
4G.

These low defaults(specifically the memory) sometimes cause the bpf
seltests to sporadically fail. So, add the option to specify memory and
also start using the max-cpu parameter with vmtest.

Signed-off-by: Puranjay Mohan <puranjay@kernel.org>
---
 .github/workflows/kernel-test.yml |  1 +
 run-vmtest/action.yml             |  6 +++++-
 run-vmtest/run.sh                 | 23 +++++++++++++++++++----
 3 files changed, 25 insertions(+), 5 deletions(-)

diff --git a/.github/workflows/kernel-test.yml b/.github/workflows/kernel-test.yml
index 4c29851..2de9ced 100644
--- a/.github/workflows/kernel-test.yml
+++ b/.github/workflows/kernel-test.yml
@@ -79,6 +79,7 @@ jobs:
           vmlinuz: '${{ github.workspace }}/vmlinuz'
           kernel-root: ${{ env.REPO_ROOT }}
           max-cpu: 8
+          max-memory: 16G
           kernel-test: ${{ inputs.test }}
           # Here we must use kbuild-output local to the repo, because
           # it was extracted from the artifacts.
diff --git a/run-vmtest/action.yml b/run-vmtest/action.yml
index 55b2dec..945d554 100644
--- a/run-vmtest/action.yml
+++ b/run-vmtest/action.yml
@@ -13,7 +13,10 @@ inputs:
     description: 'kernel source dir'
     default: '.'
   max-cpu:
-    description: 'Maximum number of CPU allocated to a VM (regardless of number of CPUs available on the host). Default is unset, e.g it will default to the number of CPU on the host.'
+    description: 'Number of CPUs allocated to the VM. Default is 2.'
+    default: ''
+  max-memory:
+    description: 'Amount of memory allocated to the VM (e.g., "4G", "16G"). Default is "4G".'
     default: ''
   kernel-test:
     description: 'Test to run'
@@ -64,6 +67,7 @@ runs:
         KERNEL_ROOT: ${{ inputs.kernel-root }}
         KERNEL_TEST: ${{ inputs.kernel-test }}
         MAX_CPU: ${{ inputs.max-cpu }}
+        MAX_MEMORY: ${{ inputs.max-memory }}
         OUTPUT_DIR: ${{ inputs.output-dir }}
         VMLINUZ: ${{ inputs.vmlinuz || '' }}
       run: |
diff --git a/run-vmtest/run.sh b/run-vmtest/run.sh
index 7a8527c..4a9eb06 100755
--- a/run-vmtest/run.sh
+++ b/run-vmtest/run.sh
@@ -86,10 +86,25 @@ foldable start vmtest "Starting virtual machine..."
 
 # Tests may be comma-separated. vmtest_selftest expect them to come from CLI space-separated.
 TEST_RUNNERS=$(echo ${KERNEL_TEST} | tr -s ',' ' ')
-vmtest -k "${VMLINUZ}" --kargs "panic=-1 sysctl.vm.panic_on_oom=1" \
-       "${GITHUB_ACTION_PATH}/vmtest-init.sh && \
-        cd '${GITHUB_WORKSPACE}'             && \
-        ${VMTEST_SCRIPT} ${TEST_RUNNERS}"
+
+# Configure VM resources
+VMTEST_NUM_CPUS=${MAX_CPU:-2}
+VMTEST_MEMORY=${MAX_MEMORY:-4G}
+
+# Generate vmtest.toml config file
+cat > vmtest.toml <<EOF
+[[target]]
+name = "vmtest"
+kernel = "${VMLINUZ}"
+kernel_args = "panic=-1 sysctl.vm.panic_on_oom=1"
+command = '''${GITHUB_ACTION_PATH}/vmtest-init.sh && cd '${GITHUB_WORKSPACE}' && ${VMTEST_SCRIPT} ${TEST_RUNNERS}'''
+
+[target.vm]
+num_cpus = ${VMTEST_NUM_CPUS}
+memory = "${VMTEST_MEMORY}"
+EOF
+
+vmtest -c vmtest.toml
 
 # fixup traffic montioring log paths if present
 PCAP_DIR=/tmp/tmon_pcap