From 119e9db233ad0f4cbd4cfb9f9385a7bca378b37d Mon Sep 17 00:00:00 2001 From: Zeng Chi Date: Mon, 21 Sep 2026 18:24:42 +0800 Subject: KVM: Don't pre-reserve xarray entries when storing empty/NULL attributes Skip the xarray reservation loop when clearing all memory attributes, as storing NULL only erases the entry and never needs to allocate, so no reservation (and no cleanup of a failed one) is required in that case. Suggested-by: Sean Christopherson Cc: David Ballesteros Signed-off-by: Zeng Chi Link: https://patch.msgid.link/20260921102442.1232375-1-zeng_chi911@163.com [sean: split to separate patch] Signed-off-by: Sean Christopherson --- tools/testing/selftests/kho/arm64.conf | 9 ++ tools/testing/selftests/kho/init.c | 75 +++++++++++++ tools/testing/selftests/kho/vmtest.sh | 190 +++++++++++++++++++++++++++++++++ tools/testing/selftests/kho/x86.conf | 7 ++ 4 files changed, 281 insertions(+) create mode 100644 tools/testing/selftests/kho/arm64.conf create mode 100644 tools/testing/selftests/kho/init.c create mode 100755 tools/testing/selftests/kho/vmtest.sh create mode 100644 tools/testing/selftests/kho/x86.conf (limited to 'tools/testing/selftests/kho') diff --git a/tools/testing/selftests/kho/arm64.conf b/tools/testing/selftests/kho/arm64.conf new file mode 100644 index 000000000..ee696807c --- /dev/null +++ b/tools/testing/selftests/kho/arm64.conf @@ -0,0 +1,9 @@ +QEMU_CMD="qemu-system-aarch64 -M virt -cpu max" +QEMU_KCONFIG=" +CONFIG_SERIAL_AMBA_PL010=y +CONFIG_SERIAL_AMBA_PL010_CONSOLE=y +CONFIG_SERIAL_AMBA_PL011=y +CONFIG_SERIAL_AMBA_PL011_CONSOLE=y +" +KERNEL_IMAGE="Image" +KERNEL_CMDLINE="console=ttyAMA0" diff --git a/tools/testing/selftests/kho/init.c b/tools/testing/selftests/kho/init.c new file mode 100644 index 000000000..88a41b6eb --- /dev/null +++ b/tools/testing/selftests/kho/init.c @@ -0,0 +1,75 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include +#include +#include +#include +#include +#include + +/* from arch/x86/include/asm/setup.h */ +#define COMMAND_LINE_SIZE 2048 + +#define KERNEL_IMAGE "/kernel" + +static int mount_filesystems(void) +{ + if (mount("debugfs", "/debugfs", "debugfs", 0, NULL) < 0) + return -1; + + return mount("proc", "/proc", "proc", 0, NULL); +} + +static long kexec_file_load(int kernel_fd, int initrd_fd, + unsigned long cmdline_len, const char *cmdline, + unsigned long flags) +{ + return syscall(__NR_kexec_file_load, kernel_fd, initrd_fd, cmdline_len, + cmdline, flags); +} + +static int kexec_load(void) +{ + char cmdline[COMMAND_LINE_SIZE]; + ssize_t len; + int fd, err; + + fd = open("/proc/cmdline", O_RDONLY); + if (fd < 0) + return -1; + + len = read(fd, cmdline, sizeof(cmdline)); + close(fd); + if (len < 0) + return -1; + + /* replace \n with \0 */ + cmdline[len - 1] = 0; + fd = open(KERNEL_IMAGE, O_RDONLY); + if (fd < 0) + return -1; + + err = kexec_file_load(fd, -1, len, cmdline, KEXEC_FILE_NO_INITRAMFS); + close(fd); + + return err ? : 0; +} + +int main(int argc, char *argv[]) +{ + if (mount_filesystems()) + goto err_reboot; + + if (kexec_load()) + goto err_reboot; + + if (reboot(RB_KEXEC)) + goto err_reboot; + + return 0; + +err_reboot: + reboot(RB_AUTOBOOT); + return -1; +} diff --git a/tools/testing/selftests/kho/vmtest.sh b/tools/testing/selftests/kho/vmtest.sh new file mode 100755 index 000000000..0014bd76e --- /dev/null +++ b/tools/testing/selftests/kho/vmtest.sh @@ -0,0 +1,190 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 + +set -ue + +CROSS_COMPILE="${CROSS_COMPILE:-""}" + +test_dir=$(realpath "$(dirname "$0")") +kernel_dir=$(realpath "$test_dir/../../../..") + +tmp_dir=$(mktemp -d /tmp/kho-test.XXXXXXXX) +headers_dir="$tmp_dir/usr" +initrd="$tmp_dir/initrd.cpio" + +source "$test_dir/../kselftest/ktap_helpers.sh" + +function usage() { + cat < "$kho_config" </dev/null || skip "$opt is missing" + done < "$kho_config" + + $make_cmd "$kimage" + $make_cmd headers_install INSTALL_HDR_PATH="$headers_dir" +} + +function mkinitrd() { + local kernel=$1 + + "$CROSS_COMPILE"gcc -s -static -Os -nostdinc -nostdlib \ + -fno-asynchronous-unwind-tables -fno-ident \ + -I "$headers_dir/include" \ + -I "$kernel_dir/tools/include/nolibc" \ + -o "$tmp_dir/init" "$test_dir/init.c" + + cat > "$tmp_dir/cpio_list" < "$initrd" +} + +function run_qemu() { + local qemu_cmd=$1 + local cmdline=$2 + local kernel=$3 + local serial="$tmp_dir/qemu.serial" + + cmdline="$cmdline kho=on panic=-1" + + $qemu_cmd -m 1G -smp 2 -no-reboot -nographic -nodefaults \ + -accel kvm -accel hvf -accel tcg \ + -serial file:"$serial" \ + -append "$cmdline" \ + -kernel "$kernel" \ + -initrd "$initrd" + + grep "KHO restore succeeded" "$serial" &> /dev/null || fail "KHO failed" +} + +function target_to_arch() { + local target=$1 + + case $target in + aarch64) echo "arm64" ;; + x86_64) echo "x86" ;; + *) skip "architecture $target is not supported" + esac +} + +function main() { + local build_dir="$kernel_dir/.kho" + local jobs=$(($(nproc) * 2)) + local target="$(uname -m)" + + # skip the test if any of the preparation steps fails + set -o errtrace + trap skip ERR + + while getopts 'hd:j:t:' opt; do + case $opt in + d) + build_dir="$OPTARG" + ;; + j) + jobs="$OPTARG" + ;; + t) + target="$OPTARG" + ;; + h) + usage + exit 0 + ;; + *) + echo Unknown argument "$opt" + usage + exit 1 + ;; + esac + done + + ktap_print_header + ktap_set_plan 1 + + if [[ "$target" != "$(uname -m)" ]] && [[ -z "$CROSS_COMPILE" ]]; then + skip "Cross-platform testing needs to specify CROSS_COMPILE" + fi + + mkdir -p "$build_dir" + local arch=$(target_to_arch "$target") + source "$test_dir/$arch.conf" + + # build the kernel and create initrd + # initrd includes the kernel image that will be kexec'ed + local make_cmd="make ARCH=$arch CROSS_COMPILE=$CROSS_COMPILE -j$jobs" + build_kernel "$build_dir" "$make_cmd" "$QEMU_KCONFIG" "$KERNEL_IMAGE" + + local kernel="$build_dir/arch/$arch/boot/$KERNEL_IMAGE" + mkinitrd "$kernel" + + run_qemu "$QEMU_CMD" "$KERNEL_CMDLINE" "$kernel" + + ktap_test_pass "KHO succeeded" +} + +main "$@" diff --git a/tools/testing/selftests/kho/x86.conf b/tools/testing/selftests/kho/x86.conf new file mode 100644 index 000000000..b419e610c --- /dev/null +++ b/tools/testing/selftests/kho/x86.conf @@ -0,0 +1,7 @@ +QEMU_CMD=qemu-system-x86_64 +QEMU_KCONFIG=" +CONFIG_SERIAL_8250=y +CONFIG_SERIAL_8250_CONSOLE=y +" +KERNEL_IMAGE="bzImage" +KERNEL_CMDLINE="console=ttyS0" -- cgit v1.3.1