From 93de2a6a4b91b72607136dd656edf03fb399d27f Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Wed, 23 Sep 2026 09:37:21 -0700 Subject: KVM: SEV: Do cache maintenance on the source VM during intra-host migration Manually perform cache maintenance on the source VM during intra-host migration to ensure no stale data is left in CPU caches after the VM is destroyed. Because the source VM is "converted" to a non-SEV VM, KVM's memory reclaim flows won't trigger cache maintenance, e.g. when all guest memory is reclaimed in response to detaching from the mmu_notifier. Note, relying on the destination VM to do cache maintenance isn't an option as KVM doesn't require identical guest memory configurations, i.e. the source VM may have access to memory that the destination VM does not. Enforcing equivalent memory configurations is infeasible, as it would require a *deep* comparison of memslots, e.g. to verify that not only are the memslot identical, but what the memslots point at is also identical. Fixes: b56639318bb2 ("KVM: SEV: Add support for SEV intra host migration") Cc: stable@vger.kernel.org Reported-by: Stefan Teodorescu Signed-off-by: Sean Christopherson Message-ID: <20260923163721.1584779-3-seanjc@google.com> Signed-off-by: Paolo Bonzini --- scripts/package/mkdebian | 273 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 273 insertions(+) create mode 100755 scripts/package/mkdebian (limited to 'scripts/package/mkdebian') diff --git a/scripts/package/mkdebian b/scripts/package/mkdebian new file mode 100755 index 000000000..d4b007b38 --- /dev/null +++ b/scripts/package/mkdebian @@ -0,0 +1,273 @@ +#!/bin/sh +# +# Copyright 2003 Wichert Akkerman +# +# Simple script to generate a debian/ directory for a Linux kernel. + +set -eu + +is_enabled() { + grep -q "^$1=y" include/config/auto.conf +} + +if_enabled_echo() { + if is_enabled "$1"; then + echo -n "$2" + elif [ $# -ge 3 ]; then + echo -n "$3" + fi +} + +set_debarch() { + if [ "${KBUILD_DEBARCH:+set}" ]; then + debarch="$KBUILD_DEBARCH" + return + fi + + # Attempt to find the correct Debian architecture + case "$UTS_MACHINE" in + i386|alpha|m68k|riscv*) + debarch="$UTS_MACHINE" ;; + x86_64) + debarch=amd64 ;; + sparc*) + debarch=sparc$(if_enabled_echo CONFIG_64BIT 64) ;; + s390*) + debarch=s390x ;; + ppc*) + if is_enabled CONFIG_64BIT; then + debarch=ppc64$(if_enabled_echo CONFIG_CPU_LITTLE_ENDIAN el) + else + debarch=powerpc$(if_enabled_echo CONFIG_SPE spe) + fi + ;; + parisc*) + debarch=hppa ;; + mips*) + if is_enabled CONFIG_CPU_LITTLE_ENDIAN; then + debarch=mips$(if_enabled_echo CONFIG_64BIT 64)$(if_enabled_echo CONFIG_CPU_MIPSR6 r6)el + elif is_enabled CONFIG_CPU_MIPSR6; then + debarch=mips$(if_enabled_echo CONFIG_64BIT 64)r6 + else + debarch=mips + fi + ;; + aarch64|arm64) + debarch=arm64 ;; + arm*) + if is_enabled CONFIG_AEABI; then + debarch=arm$(if_enabled_echo CONFIG_VFP hf el) + else + debarch=arm + fi + ;; + openrisc) + debarch=or1k ;; + sh) + if is_enabled CONFIG_CPU_SH3; then + debarch=sh3$(if_enabled_echo CONFIG_CPU_BIG_ENDIAN eb) + elif is_enabled CONFIG_CPU_SH4; then + debarch=sh4$(if_enabled_echo CONFIG_CPU_BIG_ENDIAN eb) + fi + ;; + um) + if is_enabled CONFIG_64BIT; then + debarch=amd64 + else + debarch=i386 + fi + ;; + loongarch64) + debarch=loong64 ;; + esac + if [ -z "$debarch" ]; then + debarch=$(dpkg-architecture -qDEB_HOST_ARCH) + echo "" >&2 + echo "** ** ** WARNING ** ** **" >&2 + echo "" >&2 + echo "Your architecture doesn't have its equivalent" >&2 + echo "Debian userspace architecture defined!" >&2 + echo "Falling back to the current host architecture ($debarch)." >&2 + echo "Please add support for $UTS_MACHINE to ${0} ..." >&2 + echo "" >&2 + fi +} + +# Create debian/source/ if it is a source package build +gen_source () +{ + mkdir -p debian/source + + echo "3.0 (quilt)" > debian/source/format + + { + echo "diff-ignore" + echo "extend-diff-ignore = .*" + } > debian/source/local-options + + # Add .config as a patch + mkdir -p debian/patches + { + echo "Subject: Add .config" + echo "Author: ${maintainer}" + echo + echo "--- /dev/null" + echo "+++ linux/.config" + diff -u /dev/null "${KCONFIG_CONFIG}" | tail -n +3 + } > debian/patches/config.patch + echo config.patch > debian/patches/series + + "${srctree}/scripts/package/gen-diff-patch" debian/patches/diff.patch + if [ -s debian/patches/diff.patch ]; then + sed -i " + 1iSubject: Add local diff + 1iAuthor: ${maintainer} + 1i + " debian/patches/diff.patch + + echo diff.patch >> debian/patches/series + else + rm -f debian/patches/diff.patch + fi +} + +rm -rf debian +mkdir debian + +user=${KBUILD_BUILD_USER:-$(id -nu)} +name=${DEBFULLNAME:-${user}} +if [ "${DEBEMAIL:+set}" ]; then + email=${DEBEMAIL} +else + buildhost=${KBUILD_BUILD_HOST:-$(hostname -f 2>/dev/null || hostname)} + email="${user}@${buildhost}" +fi +maintainer="${name} <${email}>" + +while [ $# -gt 0 ]; do + case "$1" in + --need-source) + gen_source + shift + ;; + *) + break + ;; + esac +done + +# Some variables and settings used throughout the script +if [ "${KDEB_PKGVERSION:+set}" ]; then + packageversion=$KDEB_PKGVERSION +else + upstream_version=$("${srctree}/scripts/setlocalversion" --no-local "${srctree}" | sed 's/-\(rc[1-9]\)/~\1/') + debian_revision=$("${srctree}/scripts/build-version") + packageversion=${upstream_version}-${debian_revision} +fi +sourcename=${KDEB_SOURCENAME:-linux-upstream} + +if [ "$ARCH" = "um" ] ; then + packagename=user-mode-linux +else + packagename=linux-image +fi + +debarch= +set_debarch + +# Try to determine distribution +if [ "${KDEB_CHANGELOG_DIST:+set}" ]; then + distribution=$KDEB_CHANGELOG_DIST +# In some cases lsb_release returns the codename as n/a, which breaks dpkg-parsechangelog +elif distribution=$(lsb_release -cs 2>/dev/null) && [ -n "$distribution" ] && [ "$distribution" != "n/a" ]; then + : # nothing to do in this case +else + distribution="unstable" + echo >&2 "Using default distribution of 'unstable' in the changelog" + echo >&2 "Install lsb-release or set \$KDEB_CHANGELOG_DIST explicitly" +fi + +echo $debarch > debian/arch + +host_gnu=$(dpkg-architecture -a "${debarch}" -q DEB_HOST_GNU_TYPE | sed 's/_/-/g') + +# Generate a simple changelog template +cat < debian/changelog +$sourcename ($packageversion) $distribution; urgency=low + + * Custom built Linux kernel. + + -- $maintainer $(date -R) +EOF + +# Generate a control file +cat < debian/control +Source: $sourcename +Section: kernel +Priority: optional +Maintainer: $maintainer +Rules-Requires-Root: no +Build-Depends: debhelper-compat (= 12) +Build-Depends-Arch: bc, bison, flex, + gcc-${host_gnu} , + kmod, libdw-dev:native, libelf-dev:native, + libssl-dev:native, libssl-dev , + python3:native, rsync +Homepage: https://www.kernel.org/ + +Package: $packagename-${KERNELRELEASE} +Architecture: $debarch +Description: Linux kernel, version ${KERNELRELEASE} + This package contains the Linux kernel, modules and corresponding other + files, version: ${KERNELRELEASE}. +EOF + +if [ "${SRCARCH}" != um ]; then +cat <> debian/control + +Package: linux-libc-dev +Section: devel +Provides: linux-kernel-headers +Architecture: $debarch +Description: Linux support headers for userspace development + This package provides userspaces headers from the Linux kernel. These headers + are used by the installed headers for GNU glibc and other system libraries. +Multi-Arch: same +EOF + +if is_enabled CONFIG_MODULES; then +cat <> debian/control + +Package: linux-headers-${KERNELRELEASE} +Architecture: $debarch +Build-Profiles: +Description: Linux kernel headers for ${KERNELRELEASE} on $debarch + This package provides kernel header files for ${KERNELRELEASE} on $debarch + . + This is useful for people who need to build external modules +EOF +fi +fi + +if is_enabled CONFIG_DEBUG_INFO; then +cat <> debian/control + +Package: linux-image-${KERNELRELEASE}-dbg +Section: debug +Architecture: $debarch +Build-Profiles: +Description: Linux kernel debugging symbols for ${KERNELRELEASE} + This package will come in handy if you need to debug the kernel. It provides + all the necessary debug symbols for the kernel and its modules. +EOF +fi + +cat < debian/rules.vars +ARCH := ${ARCH} +KERNELRELEASE := ${KERNELRELEASE} +EOF + +cp "${srctree}/scripts/package/debian/copyright" debian/ +cp "${srctree}/scripts/package/debian/rules" debian/ + +exit 0 -- cgit v1.3.1