Merge "Create an arm64 kernel module to test arm64 KMI" am: f1f176fa45 am: 9f9be21a51 am: 07f00284ed am: 8ecad96fa6

Original change: https://android-review.googlesource.com/c/platform/development/+/1816780

Change-Id: Idf071c8d1919a727a081307369e164b9a4a0e2f4

gki/kmi_abi_chk/Makefile

@@ -0,0 +1,30 @@
+# Copyright (C) 2021 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+kmi_sym-objs := kmi_sym_main.o kmi_sym_list.o
+obj-m += kmi_sym.o
+
+GKI_VER ?= 5.10
+GKI_DIR ?= ${ANDROID_BUILD_TOP}/kernel
+KSRC=${GKI_DIR}/out/android12-${GKI_VER}/common
+
+GKI_BID ?= 7618735
+CFLAGS_kmi_sym_main.o = -DGKI_BID=${GKI_BID}
+
+all:
+	make -C $(KSRC) M=$(PWD) modules
+	mv kmi_sym.ko kmi_sym-a12-${GKI_VER}.ko
+
+clean:
+	make -C $(KSRC) M=$(PWD) clean

gki/kmi_abi_chk/README

@@ -0,0 +1,59 @@
+
+#
+# How to build the KMI ABI test kernel module, kmi_sym.ko
+#
+
+1. Set up the GKI source.
+   # Set up and export GKI_DIR to be used for kernel module building
+   $ cd $GKI_DIR
+   $ repo init -u https://android.googlesource.com/kernel/manifest \
+       -b common-android12-5.10
+   $ repo sync
+   See "GKI Monthly Branch Handbook" for details.
+2. Build arm64 GKI under $GKI_DIR
+   $ BUILD_CONFIG=common/build.config.gki.aarch64 build/build.sh -j16
+3. Download a supported kernel symbol file, vmlinux.symvers, from GKI AB:
+   $ export GKI_BID=7618735
+   https://ci.android.com/builds/submitted/$GKI_BID/kernel_aarch64/latest
+   $ cp vmlinux.symvers $ANDROID_BUILD_TOP/development/gki/kmi_abi_chk/vmlinux.symvers-$GKI_BID
+4. Replace the Module.symvers just built with the supported kernel symbol file.
+   $ cp vmlinux.symvers $GKI_DIR/out/android12-5.10/common/Module.symvers
+5. Create the KMI symbol list
+   $ cd development/gki/kmi_abi_chk
+   $ cp $GKI_DIR/out/android12-5.10/common/Module.symvers vmlinux.symvers-$GKI_BID
+   $ awk '{printf("\t.xword\t%s\n",$2)}' vmlinux.symvers-$GKI_BID >> kmi_sym_list.inc
+   Note that kmi_sym_list.inc included in the current directory is a version
+   modified from the one based on vmlinux.symvers of build 7618735, the initial
+   GKI 5.10 released in July, 2021. Search b/197035344 in it for details.
+6. Build the kernel module
+   $ make ARCH=arm64 CROSS_COMPILE=aarch64 LLVM=1 LLVM_IAS=1 LTO=thin
+
+A prebuilt test kernel module, kmi_sym-7618735.ko, for arm64 GKI 5.10
+2021-07 and later builds is included in the current directory.
+
+#
+# How to use/run KMI test kernel module, kmi_sym.ko, on GKI
+#
+
+1. Copy the test kernel module to the Android device
+   $ adb push kmi_sym.ko /data/local/tmp
+2. "Root" the Android device we'd like to run the test
+   $ adb root
+3. Check the kernel information on the device
+   emulator64_arm64:/ # uname -a
+   Linux localhost 5.10.43-android12-9-00005-g376ecc372342-ab7614753 #1 SMP PREEMPT Thu Aug 5 15:12:49 UTC 2021 aarch64
+4. Load the test kernel module
+   emulator64_arm64:/ # lsmod | grep kmi_sym
+   emulator64_arm64:/ # insmod /data/local/tmp/kmi_sym.ko; echo $?
+   0
+5. Verify the test kernel module is loaded successfully
+   emulator64_arm64:/ # lsmod | grep kmi_sym
+   kmi_sym                57344  0
+   emulator64_arm64:/ # dmesg | grep KMI
+   [ 1669.833480] 5317 KMI ABI symbols at 00000000d34c59ea
+6. Unload the test kernel module
+   emulator64_arm64:/ # rmmod kmi_sym; echo $?
+   0
+   emulator64_arm64:/ # dmesg | grep KMI
+   [ 1669.833480] 5317 KMI ABI symbols at 00000000d34c59ea
+   [ 1860.571944] Cleaning up KMI ABI.

gki/kmi_abi_chk/kmi_sym_list.S

@@ -0,0 +1,29 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+*/
+
+	.text
+	.file	"kmi_sym_lst.S"
+	.type	kmi_sym_arr,@object                    // @kmi_sym_arr
+	.section	.rodata,"a",@progbits
+	.globl	kmi_sym_arr
+	.p2align	3
+
+kmi_sym_arr:
+
+#include "kmi_sym_list.inc"
+
+	.xword	0
+	.size	kmi_sym_arr, . - kmi_sym_arr

gki/kmi_abi_chk/kmi_sym_main.c

@@ -0,0 +1,46 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <linux/module.h>    // included for all kernel modules
+#include <linux/kernel.h>    // included for KERN_INFO
+#include <linux/init.h>      // included for __init and __exit macros
+#include <linux/stringify.h>
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("A kernel module using all GKI KMI symbols");
+MODULE_IMPORT_NS(CRYPTO_INTERNAL);
+
+extern void *kmi_sym_arr[];
+
+static int __init kmi_sym_init(void)
+{
+	int cnt;
+
+	for (cnt = 0; kmi_sym_arr[cnt] != 0; ++cnt)
+		;
+	printk(KERN_INFO "GKI build: %s\n", __stringify(GKI_BID));
+	printk(KERN_INFO "%d GKI KMI symbols at %p\n", cnt, kmi_sym_arr);
+
+	return 0;
+}
+
+static void __exit kmi_sym_cleanup(void)
+{
+	printk(KERN_INFO "Cleaning up GKI KMI test.\n");
+}
+
+module_init(kmi_sym_init);
+module_exit(kmi_sym_cleanup);