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[libvirt] [PATCH python 0/2] spec: fedora tweaks
by Cole Robinson 04 Jul '19

04 Jul '19

Some fedora version tweaks Cole Robinson (2): spec: Unconditionally build python2 on Fedora spec: Bump minimum supported Fedora version to 29 libvirt-python.spec.in | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) -- 2.21.0

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[libvirt] [PATCH] remote: remove unused constant for libvirtd config file
by Daniel P. Berrangé 04 Jul '19

04 Jul '19

The LIBVIRTD_CONFIGURATION_FILE constant was introduced in commit b7c42619e69acd8416be88b8aa3b4161bc813f8a Author: Richard W.M. Jones <rjones(a)redhat.com> Date: Mon Jun 11 11:43:41 2007 +0000 Mon Jun 11 12:41:00 BST 2007 Richard W.M. Jones <rjones(a)redhat.com> and then never used ! Signed-off-by: Daniel P. Berrangé <berrange(a)redhat.com> --- Pushed under the trivial rule src/remote/remote_driver.h | 1 - 1 file changed, 1 deletion(-) diff --git a/src/remote/remote_driver.h b/src/remote/remote_driver.h index 8c7da6b000..132e478ef3 100644 --- a/src/remote/remote_driver.h +++ b/src/remote/remote_driver.h @@ -34,7 +34,6 @@ unsigned long remoteVersion(void); #define LIBVIRTD_PRIV_UNIX_SOCKET LOCALSTATEDIR "/run/libvirt/libvirt-sock" #define LIBVIRTD_PRIV_UNIX_SOCKET_RO LOCALSTATEDIR "/run/libvirt/libvirt-sock-ro" #define LIBVIRTD_USER_UNIX_SOCKET "libvirt-sock" -#define LIBVIRTD_CONFIGURATION_FILE SYSCONFDIR "/libvirt/libvirtd.conf" /* Defaults for PKI directory. */ #define LIBVIRT_PKI_DIR SYSCONFDIR "/pki" -- 2.21.0

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[libvirt] ANNOUNCE: virt-manager 2.2.1 released
by Cole Robinson 04 Jul '19

04 Jul '19

I'm happy to announce the release of virt-manager 2.2.1! virt-manager is a desktop application for managing KVM, Xen, and LXC virtualization via libvirt. The release can be downloaded from: http://virt-manager.org/download/ This release includes: - CVE-2019-10183: Replace --unattended user-password and admin-password with user-password-file and admin-password-file (Fabiano Fidêncio) - Consistent --memballoon default across non-x86 (Andrea Bolognani) - virt-install: add --numatune memnode.* (Athina Plaskasoviti) - Drop hard dep on gtksourceview4, gtksourceview3 is fine as well Thanks to everyone who has contributed to this release through testing, bug reporting, submitting patches, and otherwise sending in feedback! Thanks, Cole

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[libvirt] [PATCH] mingw: distribute schemas/networkport.rng
by Cole Robinson 03 Jul '19

03 Jul '19

Signed-off-by: Cole Robinson <crobinso(a)redhat.com> --- Pushed as a build breaker. Anyone know why we list these explicitly rather than use a wildcard? libvirt.spec.in is the same mingw-libvirt.spec.in | 2 ++ 1 file changed, 2 insertions(+) diff --git a/mingw-libvirt.spec.in b/mingw-libvirt.spec.in index 280db4d1aa..ad6d6e952e 100644 --- a/mingw-libvirt.spec.in +++ b/mingw-libvirt.spec.in @@ -237,6 +237,7 @@ rm -rf $RPM_BUILD_ROOT%{mingw64_libexecdir}/libvirt-guests.sh %{mingw32_datadir}/libvirt/schemas/interface.rng %{mingw32_datadir}/libvirt/schemas/network.rng %{mingw32_datadir}/libvirt/schemas/networkcommon.rng +%{mingw32_datadir}/libvirt/schemas/networkport.rng %{mingw32_datadir}/libvirt/schemas/nodedev.rng %{mingw32_datadir}/libvirt/schemas/nwfilter.rng %{mingw32_datadir}/libvirt/schemas/nwfilter_params.rng @@ -325,6 +326,7 @@ rm -rf $RPM_BUILD_ROOT%{mingw64_libexecdir}/libvirt-guests.sh %{mingw64_datadir}/libvirt/schemas/interface.rng %{mingw64_datadir}/libvirt/schemas/network.rng %{mingw64_datadir}/libvirt/schemas/networkcommon.rng +%{mingw64_datadir}/libvirt/schemas/networkport.rng %{mingw64_datadir}/libvirt/schemas/nodedev.rng %{mingw64_datadir}/libvirt/schemas/nwfilter.rng %{mingw64_datadir}/libvirt/schemas/nwfilter_params.rng -- 2.21.0

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[libvirt] [PATCH] Do not keep empty log files for deleted domains
by Jan Zerebecki 03 Jul '19

03 Jul '19

With logrotates copytruncate when e.g. domain1 doesn't exist anymore /var/log/libvirt/qemu/domain1.log will still exist after rotation even though it will never be written to. When new domain names keep getting used this leads to a lot of empty logfiles. This may lead to slowdown or lack of free disk space / inodes. Fix this by replacing copytruncate with the apropriate postrotate command to reopen log files. Thus after the apropriate time log files for deleted domains will be gone. This also has the advantage that the chance for loss of a few lines during copytruncate is gone. Signed-off-by: Jan Zerebecki <jan.suse(a)zerebecki.de> --- src/remote/libvirtd.libxl.logrotate.in | 4 +++- src/remote/libvirtd.logrotate.in | 4 +++- src/remote/libvirtd.lxc.logrotate.in | 4 +++- src/remote/libvirtd.qemu.logrotate.in | 4 +++- 4 files changed, 12 insertions(+), 4 deletions(-) diff --git a/src/remote/libvirtd.libxl.logrotate.in b/src/remote/libvirtd.libxl.logrotate.in index cb7f07d846..d4f25f8cab 100644 --- a/src/remote/libvirtd.libxl.logrotate.in +++ b/src/remote/libvirtd.libxl.logrotate.in @@ -4,5 +4,7 @@ rotate 4 compress delaycompress - copytruncate + postrotate + /usr/bin/killall -USR1 virtlogd + endscript } diff --git a/src/remote/libvirtd.logrotate.in b/src/remote/libvirtd.logrotate.in index 4e02510c8b..73dab7579f 100644 --- a/src/remote/libvirtd.logrotate.in +++ b/src/remote/libvirtd.logrotate.in @@ -4,6 +4,8 @@ rotate 4 compress delaycompress - copytruncate minsize 100k + postrotate + /usr/bin/killall -USR1 virtlogd + endscript } diff --git a/src/remote/libvirtd.lxc.logrotate.in b/src/remote/libvirtd.lxc.logrotate.in index 2bb9dfba12..eed47bb55f 100644 --- a/src/remote/libvirtd.lxc.logrotate.in +++ b/src/remote/libvirtd.lxc.logrotate.in @@ -4,5 +4,7 @@ rotate 4 compress delaycompress - copytruncate + postrotate + /usr/bin/killall -USR1 virtlogd + endscript } diff --git a/src/remote/libvirtd.qemu.logrotate.in b/src/remote/libvirtd.qemu.logrotate.in index cdb399ef23..95407cec1a 100644 --- a/src/remote/libvirtd.qemu.logrotate.in +++ b/src/remote/libvirtd.qemu.logrotate.in @@ -4,5 +4,7 @@ rotate 4 compress delaycompress - copytruncate + postrotate + /usr/bin/killall -USR1 virtlogd + endscript } -- 2.20.1

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[libvirt] [PATCH] remote: remove obsolete rule for generating sysvinit script
by Daniel P. Berrangé 03 Jul '19

03 Jul '19

The sysvinit script was previously removed in commit 912fe2df9d8628b2f3d54485f1cb919cb124d07a Author: Andrea Bolognani <abologna(a)redhat.com> Date: Fri Mar 15 16:47:27 2019 +0100 Drop support for "Red Hat" init scripts A make rule was accidentally left behind. Signed-off-by: Daniel P. Berrangé <berrange(a)redhat.com> --- src/remote/Makefile.inc.am | 9 --------- 1 file changed, 9 deletions(-) diff --git a/src/remote/Makefile.inc.am b/src/remote/Makefile.inc.am index 013cd3e382..43ad53bedb 100644 --- a/src/remote/Makefile.inc.am +++ b/src/remote/Makefile.inc.am @@ -296,15 +296,6 @@ INSTALL_DATA_LOCAL += install-sasl UNINSTALL_LOCAL += uninstall-sasl endif WITH_SASL -libvirtd.init: remote/libvirtd.init.in $(top_builddir)/config.status - $(AM_V_GEN)sed \ - -e 's|[@]localstatedir[@]|$(localstatedir)|g' \ - -e 's|[@]sbindir[@]|$(sbindir)|g' \ - -e 's|[@]sysconfdir[@]|$(sysconfdir)|g' \ - < $< > $@-t && \ - chmod a+x $@-t && \ - mv $@-t $@ - libvirtd.service: remote/libvirtd.service.in $(top_builddir)/config.status $(AM_V_GEN)sed \ -e 's|[@]localstatedir[@]|$(localstatedir)|g' \ -- 2.21.0

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[libvirt] [PATCH] remote: remove obsolete params from sysconf file
by Daniel P. Berrangé 03 Jul '19

03 Jul '19

The LIBVIRTD_CONFIG and LIBVIRTD_NOFILES_LIMIT parameters were only honoured when using the sysvinit scripts. This was removed already in commit 912fe2df9d8628b2f3d54485f1cb919cb124d07a Author: Andrea Bolognani <abologna(a)redhat.com> Date: Fri Mar 15 16:47:27 2019 +0100 Drop support for "Red Hat" init scripts so the parameters can safely be dropped. Signed-off-by: Daniel P. Berrangé <berrange(a)redhat.com> --- src/remote/libvirtd.sysconf | 18 +----------------- 1 file changed, 1 insertion(+), 17 deletions(-) diff --git a/src/remote/libvirtd.sysconf b/src/remote/libvirtd.sysconf index f15e5956eb..60a47c252f 100644 --- a/src/remote/libvirtd.sysconf +++ b/src/remote/libvirtd.sysconf @@ -1,8 +1,4 @@ -# Override the default config file -# NOTE: This setting is no longer honoured if using -# systemd. Set '--config /etc/libvirt/libvirtd.conf' -# in LIBVIRTD_ARGS instead. -#LIBVIRTD_CONFIG=/etc/libvirt/libvirtd.conf +# Customizations for the libvirtd.service systemd unit # Listen for TCP/IP connections # NB. must setup TLS/SSL keys prior to using this @@ -19,15 +15,3 @@ #QEMU_AUDIO_DRV=sdl # #SDL_AUDIODRIVER=pulse - -# Override the maximum number of opened files. -# This only works with traditional init scripts. -# In the systemd world, the limit can only be changed by overriding -# LimitNOFILE for libvirtd.service. To do that, just create a *.conf -# file in /etc/systemd/system/libvirtd.service.d/ (for example -# /etc/systemd/system/libvirtd.service.d/openfiles.conf) and write -# the following two lines in it: -# [Service] -# LimitNOFILE=2048 -# -#LIBVIRTD_NOFILES_LIMIT=2048 -- 2.21.0

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[libvirt] [PATCH v2 0/4] tests: Add and use more DO_TEST_CAPS_*() macros
by Andrea Bolognani 03 Jul '19

03 Jul '19

Changes from [v1]: * split 1/2 into three separate patches for easier review. [v1] https://www.redhat.com/archives/libvir-list/2019-July/msg00069.html Andrea Bolognani (4): tests: Reorder DO_TEST_CAPS_*() macros tests: Add DO_TEST_CAPS_ARCH_VER_FULL() tests: Add more DO_TEST_CAPS_*() macros tests: Use the new DO_TEST_CAPS_*() macros tests/qemuxml2argvtest.c | 76 ++++++++++++++++++++-------------------- tests/qemuxml2xmltest.c | 32 +++++++++-------- 2 files changed, 55 insertions(+), 53 deletions(-) -- 2.21.0

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[libvirt] [PATCH] qemu: De-duplicate some path definitions
by Michal Privoznik 03 Jul '19

03 Jul '19

There are some paths (e.g. /dev/vfio/vfio or /dev/mapper/control) which are defined in qemu_domain.c and then in qemu_cgroup.c again. This is suboptimal. Lets move paths into qemu_domain.h and drop duplicate definitions. Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com> --- src/qemu/qemu_cgroup.c | 13 ++++++------- src/qemu/qemu_domain.c | 30 +++++++++++------------------- src/qemu/qemu_domain.h | 7 +++++++ src/qemu/qemu_hostdev.c | 5 +++-- 4 files changed, 27 insertions(+), 28 deletions(-) diff --git a/src/qemu/qemu_cgroup.c b/src/qemu/qemu_cgroup.c index ca76c4fdfa..19ca60905a 100644 --- a/src/qemu/qemu_cgroup.c +++ b/src/qemu/qemu_cgroup.c @@ -113,8 +113,6 @@ qemuSetupImagePathCgroup(virDomainObjPtr vm, } -#define DEVICE_MAPPER_CONTROL_PATH "/dev/mapper/control" - static int qemuSetupImageCgroupInternal(virDomainObjPtr vm, virStorageSourcePtr src, @@ -127,8 +125,8 @@ qemuSetupImageCgroupInternal(virDomainObjPtr vm, } if (virStoragePRDefIsManaged(src->pr) && - virFileExists(DEVICE_MAPPER_CONTROL_PATH) && - qemuSetupImagePathCgroup(vm, DEVICE_MAPPER_CONTROL_PATH, false) < 0) + virFileExists(QEMU_DEVICE_MAPPER_CONTROL_PATH) && + qemuSetupImagePathCgroup(vm, QEMU_DEVICE_MAPPER_CONTROL_PATH, false) < 0) return -1; return qemuSetupImagePathCgroup(vm, src->path, src->readonly || forceReadonly); @@ -162,7 +160,7 @@ qemuTeardownImageCgroup(virDomainObjPtr vm, return 0; } - if (virFileExists(DEVICE_MAPPER_CONTROL_PATH)) { + if (virFileExists(QEMU_DEVICE_MAPPER_CONTROL_PATH)) { for (i = 0; i < vm->def->ndisks; i++) { virStorageSourcePtr diskSrc = vm->def->disks[i]->src; @@ -176,9 +174,10 @@ qemuTeardownImageCgroup(virDomainObjPtr vm, if (i == vm->def->ndisks) { VIR_DEBUG("Disabling device mapper control"); ret = virCgroupDenyDevicePath(priv->cgroup, - DEVICE_MAPPER_CONTROL_PATH, perms, true); + QEMU_DEVICE_MAPPER_CONTROL_PATH, + perms, true); virDomainAuditCgroupPath(vm, priv->cgroup, "deny", - DEVICE_MAPPER_CONTROL_PATH, + QEMU_DEVICE_MAPPER_CONTROL_PATH, virCgroupGetDevicePermsString(perms), ret); if (ret < 0) return ret; diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c index 0f1335de9c..7e6a9764c5 100644 --- a/src/qemu/qemu_domain.c +++ b/src/qemu/qemu_domain.c @@ -117,14 +117,6 @@ VIR_ENUM_IMPL(qemuDomainNamespace, "mount", ); - -#define PROC_MOUNTS "/proc/mounts" -#define DEVPREFIX "/dev/" -#define DEV_VFIO "/dev/vfio/vfio" -#define DEVICE_MAPPER_CONTROL_PATH "/dev/mapper/control" -#define DEV_SEV "/dev/sev" - - struct _qemuDomainLogContext { virObject parent; @@ -11872,7 +11864,7 @@ qemuDomainGetHostdevPath(virDomainDefPtr def, tmpPerms[0] = perm; if (includeVFIO) { - if (VIR_STRDUP(tmpPaths[1], DEV_VFIO) < 0) + if (VIR_STRDUP(tmpPaths[1], QEMU_DEV_VFIO) < 0) goto cleanup; tmpPerms[1] = VIR_CGROUP_DEVICE_RW; } @@ -11919,7 +11911,7 @@ qemuDomainGetPreservedMountPath(virQEMUDriverConfigPtr cfg, { char *path = NULL; char *tmp; - const char *suffix = mountpoint + strlen(DEVPREFIX); + const char *suffix = mountpoint + strlen(QEMU_DEVPREFIX); char *domname = virDomainDefGetShortName(vm->def); size_t off; @@ -11974,7 +11966,7 @@ qemuDomainGetPreservedMounts(virQEMUDriverConfigPtr cfg, char **paths = NULL, **mounts = NULL; size_t i, j, nmounts; - if (virFileGetMountSubtree(PROC_MOUNTS, "/dev", + if (virFileGetMountSubtree(QEMU_PROC_MOUNTS, "/dev", &mounts, &nmounts) < 0) goto error; @@ -12099,7 +12091,7 @@ qemuDomainCreateDeviceRecursive(const char *device, * Otherwise we might get fooled with `/dev/../var/my_image'. * For now, lets hope callers play nice. */ - if (STRPREFIX(device, DEVPREFIX)) { + if (STRPREFIX(device, QEMU_DEVPREFIX)) { size_t i; for (i = 0; i < data->ndevMountsPath; i++) { @@ -12113,7 +12105,7 @@ qemuDomainCreateDeviceRecursive(const char *device, /* Okay, @device is in /dev but not in any mount point under /dev. * Create it. */ if (virAsprintf(&devicePath, "%s/%s", - data->path, device + strlen(DEVPREFIX)) < 0) + data->path, device + strlen(QEMU_DEVPREFIX)) < 0) goto cleanup; if (virFileMakeParentPath(devicePath) < 0) { @@ -12375,7 +12367,7 @@ qemuDomainSetupDisk(virQEMUDriverConfigPtr cfg ATTRIBUTE_UNUSED, /* qemu-pr-helper might require access to /dev/mapper/control. */ if (disk->src->pr && - qemuDomainCreateDevice(DEVICE_MAPPER_CONTROL_PATH, data, true) < 0) + qemuDomainCreateDevice(QEMU_DEVICE_MAPPER_CONTROL_PATH, data, true) < 0) goto cleanup; ret = 0; @@ -12707,7 +12699,7 @@ qemuDomainSetupLaunchSecurity(virQEMUDriverConfigPtr cfg ATTRIBUTE_UNUSED, VIR_DEBUG("Setting up launch security"); - if (qemuDomainCreateDevice(DEV_SEV, data, false) < 0) + if (qemuDomainCreateDevice(QEMU_DEV_SEV, data, false) < 0) return -1; VIR_DEBUG("Set up launch security"); @@ -13122,7 +13114,7 @@ qemuDomainAttachDeviceMknodRecursive(virQEMUDriverPtr driver, isReg = S_ISREG(data.sb.st_mode) || S_ISFIFO(data.sb.st_mode) || S_ISSOCK(data.sb.st_mode); isDir = S_ISDIR(data.sb.st_mode); - if ((isReg || isDir) && STRPREFIX(file, DEVPREFIX)) { + if ((isReg || isDir) && STRPREFIX(file, QEMU_DEVPREFIX)) { cfg = virQEMUDriverGetConfig(driver); if (!(target = qemuDomainGetPreservedMountPath(cfg, vm, file))) goto cleanup; @@ -13178,7 +13170,7 @@ qemuDomainAttachDeviceMknodRecursive(virQEMUDriverPtr driver, } # endif - if (STRPREFIX(file, DEVPREFIX)) { + if (STRPREFIX(file, QEMU_DEVPREFIX)) { size_t i; for (i = 0; i < ndevMountsPath; i++) { @@ -13287,7 +13279,7 @@ qemuDomainDetachDeviceUnlink(virQEMUDriverPtr driver ATTRIBUTE_UNUSED, int ret = -1; size_t i; - if (STRPREFIX(file, DEVPREFIX)) { + if (STRPREFIX(file, QEMU_DEVPREFIX)) { for (i = 0; i < ndevMountsPath; i++) { if (STREQ(devMountsPath[i], "/dev")) continue; @@ -13429,7 +13421,7 @@ qemuDomainNamespaceSetupDisk(virDomainObjPtr vm, /* qemu-pr-helper might require access to /dev/mapper/control. */ if (src->pr && - (VIR_STRDUP(dmPath, DEVICE_MAPPER_CONTROL_PATH) < 0 || + (VIR_STRDUP(dmPath, QEMU_DEVICE_MAPPER_CONTROL_PATH) < 0 || VIR_APPEND_ELEMENT_COPY(paths, npaths, dmPath) < 0)) goto cleanup; diff --git a/src/qemu/qemu_domain.h b/src/qemu/qemu_domain.h index 5cb4a32c0e..3eea8b0f96 100644 --- a/src/qemu/qemu_domain.h +++ b/src/qemu/qemu_domain.h @@ -223,6 +223,13 @@ struct _qemuDomainUnpluggingDevice { }; +#define QEMU_PROC_MOUNTS "/proc/mounts" +#define QEMU_DEVPREFIX "/dev/" +#define QEMU_DEV_VFIO "/dev/vfio/vfio" +#define QEMU_DEV_SEV "/dev/sev" +#define QEMU_DEVICE_MAPPER_CONTROL_PATH "/dev/mapper/control" + + typedef enum { QEMU_DOMAIN_NS_MOUNT = 0, QEMU_DOMAIN_NS_LAST diff --git a/src/qemu/qemu_hostdev.c b/src/qemu/qemu_hostdev.c index cc0a4574cd..efa4d62f1f 100644 --- a/src/qemu/qemu_hostdev.c +++ b/src/qemu/qemu_hostdev.c @@ -25,6 +25,7 @@ #include <sys/ioctl.h> #include "qemu_hostdev.h" +#include "qemu_domain.h" #include "virlog.h" #include "virerror.h" #include "viralloc.h" @@ -140,7 +141,7 @@ qemuHostdevHostSupportsPassthroughVFIO(void) return false; /* condition 2 - /dev/vfio/vfio exists */ - if (!virFileExists("/dev/vfio/vfio")) + if (!virFileExists(QEMU_DEV_VFIO)) return false; return true; @@ -343,7 +344,7 @@ qemuHostdevPrepareMediatedDevices(virQEMUDriverPtr driver, /* Checking for VFIO only is fine with mdev, as IOMMU isolation is achieved * by the physical parent device. */ - supportsVFIO = virFileExists("/dev/vfio/vfio"); + supportsVFIO = virFileExists(QEMU_DEV_VFIO); for (i = 0; i < nhostdevs; i++) { if (virHostdevIsMdevDevice(hostdevs[i])) { -- 2.21.0

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[libvirt] [PATCH v3] docs: Provide documentation for SEV launch security
by Erik Skultety 03 Jul '19

03 Jul '19

Signed-off-by: Erik Skultety <eskultet(a)redhat.com> --- Since v2: - incorporated Brijesh's notes into the SEV description and fixed the info about SME docs/launch_security_sev.html.in | 521 +++++++++++++++++++++++++++++++ 1 file changed, 521 insertions(+) create mode 100644 docs/launch_security_sev.html.in diff --git a/docs/launch_security_sev.html.in b/docs/launch_security_sev.html.in new file mode 100644 index 0000000000..923bb52b25 --- /dev/null +++ b/docs/launch_security_sev.html.in @@ -0,0 +1,521 @@ +<?xml version="1.0" encoding="UTF-8"?> +<!DOCTYPE html> +<html xmlns="http://www.w3.org/1999/xhtml"> + <body> + <h1>Launch security with AMD SEV</h1> + + <ul id="toc"></ul> + + <p> + Storage encryption in modern public cloud computing is a common practice. + However, from the point of view of a user of these cloud workloads, a + significant amount of trust needs to be put in the cloud platform security as + well as integrity (was the hypervisor tampered?). For this reason there's ever + rising demand for securing data in use, i.e. memory encryption. + One of the solutions addressing this matter is AMD SEV. + </p> + + <h2>AMD SEV</h2> + <p> + SEV (Secure Encrypted Virtualization) is a feature extension of AMD's SME (Secure + Memory Encryption) intended for KVM virtual machines which is supported + primarily on AMD's EPYC CPU line. In contrast to SME, SEV uses a unique memory encryption + key for each VM. The whole encryption of memory pages is completely transparent + to the hypervisor and happens inside dedicated hardware in the on-die memory controller. + Each controller includes a high-performance Advanced Encryption Standard + (AES) engine that encrypts data when it is written to DRAM and decrypts it + when read. + + For more details about the technology itself, you can visit + <a href="https://developer.amd.com/sev/">AMD's developer portal</a>. + </p> + + <h2><a id="Host">Enabling SEV on the host</a></h2> + <p> + Before VMs can make use of the SEV feature you need to make sure your + AMD CPU does support SEV. You can check whether SEV is among the CPU + flags with: + </p> + + <pre> +$ cat /proc/cpuinfo | grep sev +... +sme ssbd sev ibpb</pre> + + <p> + Next step is to enable SEV in the kernel, because it is disabled by default. + This is done by putting the following onto the kernel command line: + </p> + + <pre> +mem_encrypt=on kvm_amd.sev=1 + </pre> + + <p> + To make the changes persistent, append the above to the variable holding + parameters of the kernel command line in + <code>/etc/default/grub</code> to preserve SEV settings across reboots + </p> + + <pre> +$ cat /etc/default/grub +... +GRUB_CMDLINE_LINUX="... mem_encrypt=on kvm_amd.sev=1" +$ grub2-mkconfig -o /boot/efi/EFI/<distro>/grub.cfg</pre> + + <p> + <code>mem_encrypt=on</code> turns on the SME memory encryption feature on + the host which protects against the physical attack on the hypervisor + memory. The <code>kvm_amd.sev</code> parameter actually enables SEV in + the kvm module. It can be set on the command line alongside + <code>mem_encrypt</code> like shown above, or it can be put into a + module config under <code>/etc/modprobe.d/</code> + </p> + + <pre> +$ cat /etc/modprobe.d/sev.conf +options kvm_amd sev=1 + </pre> + + <p> + After rebooting the host, you should see SEV being enabled in the kernel: + </p> + + <pre> +$ cat /sys/module/kvm_amd/parameters/sev +1 + </pre> + + <h2><a id="Virt">Checking SEV support in the virt stack</a></h2> + <p> + <b>Note: All of the commands bellow need to be run with root privileges.</b> + </p> + + <p> + First make sure you have the following packages in the specified versions: + </p> + + <ul> + <li> + libvirt >= 4.5.0 (>5.1.0 recommended due to additional SEV bugfixes) + </li> + <li> + QEMU >= 2.12.0 + </li> + </ul> + <p> + To confirm that the virtualization stack supports SEV, run the following: + </p> + + <pre> +# virsh domcapabilities +<domainCapabilities> +... + <features> + ... + <sev supported='yes'> + <cbitpos>47</cbitpos> + <reducedPhysBits>1</reducedPhysBits> + </sev> + ... + </features> +</domainCapabilities></pre> + <p> + Note that if libvirt was already installed and libvirtd running before enabling SEV in the kernel followed by the host reboot you need to force libvirtd + to re-probe both the host and QEMU capabilities. First stop libvirtd: + </p> + + <pre> +# systemctl stop libvirtd.service + </pre> + + <p> + Now you need to clean the capabilities cache: + </p> + + <pre> +# rm -f /var/cache/libvirt/qemu/capabilities/* + </pre> + + <p> + If you now restart libvirtd, it will re-probe the capabilities and if + you now run: + </p> + + <pre> +# virsh domcapabilities + </pre> + + <p> + SEV should be listed as supported. If you still see: + </p> + + <pre> +<sev supported='no'/> + </pre> + + <p> + it means one of two things: + <ol> + <li> + libvirt does support SEV, but either QEMU or the host does not + </li> + <li> + you have libvirt <=5.1.0 which suffered from getting a + <code>'Permission denied'</code> on <code>/dev/sev</code> because + of the default permissions on the character device which prevented + QEMU from opening it during capabilities probing - you can either + manually tweak the permissions so that QEMU has access to it or + preferably install libvirt 5.1.0 or higher + </li> + </ol> + </p> + + <h2><a id="Configuration">VM Configuration</a></h2> + <p> + SEV is enabled in the XML by specifying the + <a href="https://libvirt.org/formatdomain.html#launchSecurity"><launchSecurity> </a> element. However, specifying <code>launchSecurity</code> isn't + enough to boot an SEV VM. Further configuration requirements are discussed + below. + </p> + + <h3><a id="Machine">Machine type</a></h3> + <p> + Even though both Q35 and legacy PC machine types (for PC see also + "virtio") can be used with SEV, usage of the legacy PC machine type is + strongly discouraged, since depending on how your OVMF package was + built (e.g. including features like SecureBoot or SMM) Q35 may even be + required. + </p> + + <h5>Q35</h5> +<pre> +... +<os> + <type arch='x86_64' machine='pc-q35-3.0'>hvm</type> + ... +</os> +...</pre> + + <h5>i440fx (discouraged)</h5> + <pre> +... +<os> + <type arch='x86_64' machine='pc-i440fx-3.0'>hvm</type> + ... +</os> +... + </pre> + + <h3><a id="Boot">Boot loader</a></h3> + <p> + SEV is only going to work with OVMF (UEFI), so you'll need to point libvirt to + the correct OVMF binary. + </p> + <pre> +... +<os> + <type arch='x86_64' machine='pc-q35-3.0'>hvm</type> + <loader readonly='yes' type='pflash'>/usr/share/edk2/ovmf/OVMF_CODE.fd</loader> +</os> +...</pre> + + <h3><a id="Memory">Memory</a></h3> + <p> + Internally, SEV expects that the encrypted memory pages won't be swapped out or move + around so the VM memory needs to be pinned in physical RAM which will be + handled by QEMU. Apart from that, certain memory regions allocated by QEMU + itself (UEFI pflash, device ROMs, video RAM, etc.) have to be encrypted as + well. This causes a conflict in how libvirt tries to protect the host. + By default, libvirt enforces a memory hard limit on each VM's cgroup in order + to protect the host from malicious QEMU to allocate and lock all the available + memory. This limit corresponds to the total memory allocation for the VM given + by <code><currentMemory></code> element. However, trying to account for the additional + memory regions QEMU allocates when calculating the limit in an automated manner + is non-deterministic. One way to resolve this is to set the hard limit manually. + + <p> + Note: Figuring out the right number so that your guest boots and isn't killed is + challenging, but 256MiB extra memory over the total guest RAM should suffice for + most workloads and may serve as a good starting point. + + For example, a domain with 4GB memory with a 256MiB extra hard limit would look + like this: + </p> + </p> + + <pre> +# virsh edit <domain> +<domain> + ... + <currentMemory unit='KiB'>4194304</currentMemory> + <memtune> + <hard_limit unit='KiB'>4456448</hard_limit> + </memtune> + ... +</domain></pre> + <p> + There's another, preferred method of taking care of the limits by + using the<code><memoryBacking></code> element along with the + <code><locked/></code> subelement: + </p> + + <pre> +<domain> + ... + <memoryBacking> + <locked/> + </memoryBacking> + ... +</domain></pre> + + <p> + What that does is that it tells libvirt not to force any hard limit (well, + unlimited) upon the VM cgroup. The obvious advantage is that one doesn't need + to determine the hard limit for every single SEV-enabled VM. However, there is + a significant security-related drawback to this approach. Since no hard limit + is applied, a malicious QEMU could perform a DoS attack by locking all of the + host's available memory. The way to avoid this issue and to protect the host is + to enforce a bigger hard limit on the master cgroup containing all of the VMs + - on systemd this is <code>machine.slice</code>. + </p> + + <pre> +# systemctl set-property machine.slice MemoryHigh=<value></pre> + + <p> + To put even stricter measures in place which would involve the OOM killer, use + <pre> +# systemctl set-property machine.slice MemoryMax=<value></pre> + instead. Alternatively, you can create a systemd config (don't forget + to reload systemd configuration in this case): + <pre> +# cat << EOF > /etc/systemd/system.control/machine.slice.d/90-MemoryMax.conf +MemoryMax=<value> +EOF</pre> + The trade-off to keep in mind with the second approach is that the VMs + can still perform DoS on each other. + </p> + + <h3><a id="Virtio">Virtio</a></h3> + <p> + In order to make virtio devices work, we need to enable emulated IOMMU + on the devices so that virtual DMA can work. + </p> + + <pre> +# virsh edit <domain> +<domain> + ... + <controller type='virtio-serial' index='0'> + <driver iommu='on'/> + </controller> + <controller type='scsi' index='0' model='virtio-scsi'> + <driver iommu='on'/> + </controller> + ... + <memballoon model='virtio'> + <driver iommu='on'/> + </memballoon> + <rng model='virtio'> + <backend model='random'>/dev/urandom</backend> + <driver iommu='on'/> + </rng> + ... +<domain></pre> + + <p> + If you for some reason want to use the legacy PC machine type, further changes + to the virtio + configuration is required, because SEV will not work with Virtio <1.0. In + libvirt, this is handled by using the virtio-non-transitional device model + (libvirt >= 5.2.0 required). + + <p> + Note: some devices like video devices don't + support non-transitional model, which means that virtio GPU cannot be used. + </p> + </p> + + <pre> +<domain> + ... + <devices> + ... + <memballoon model='virtio-non-transitional'> + <driver iommu='on'/> + </memballoon> + </devices> + ... +</domain></pre> + + <h2><a id="Limitations">Limitations</a></h2> + <p> + Currently, the boot disk cannot be of type virtio-blk, instead, virtio-scsi + needs to be used if virtio is desired. This limitation is expected to be lifted + with future releases of kernel (the kernel used at the time of writing the + article is 5.0.14). + If you still cannot start an SEV VM, it could be because of wrong SELinux label on the <code>/dev/sev</code> device with selinux-policy <3.14.2.40 which prevents QEMU from touching the device. This can be resolved by upgrading the package, tuning the selinux policy rules manually to allow svirt_t to access the device (see <code>audit2allow</code> on how to do that) or putting SELinux into permissive mode (discouraged). + </p> + + <h2><a id="Examples">Full domain XML examples</a></h2> + + <h5>Q35 machine</h5> + <pre> +<domain type='kvm'> + <name>sev-dummy</name> + <memory unit='KiB'>4194304</memory> + <currentMemory unit='KiB'>4194304</currentMemory> + <memoryBacking> + <locked/> + </memoryBacking> + <vcpu placement='static'>4</vcpu> + <os> + <type arch='x86_64' machine='pc-q35-3.0'>hvm</type> + <loader readonly='yes' type='pflash'>/usr/share/edk2/ovmf/OVMF_CODE.fd</loader> + <nvram>/var/lib/libvirt/qemu/nvram/sev-dummy_VARS.fd</nvram> + </os> + <features> + <acpi/> + <apic/> + <vmport state='off'/> + </features> + <cpu mode='host-model' check='partial'> + <model fallback='allow'/> + </cpu> + <clock offset='utc'> + <timer name='rtc' tickpolicy='catchup'/> + <timer name='pit' tickpolicy='delay'/> + <timer name='hpet' present='no'/> + </clock> + <on_poweroff>destroy</on_poweroff> + <on_reboot>restart</on_reboot> + <on_crash>destroy</on_crash> + <pm> + <suspend-to-mem enabled='no'/> + <suspend-to-disk enabled='no'/> + </pm> + <devices> + <emulator>/usr/bin/qemu-kvm</emulator> + <disk type='file' device='disk'> + <driver name='qemu' type='qcow2'/> + <source file='/var/lib/libvirt/images/sev-dummy.qcow2'/> + <target dev='sda' bus='scsi'/> + <boot order='1'/> + </disk> + <controller type='virtio-serial' index='0'> + <driver iommu='on'/> + </controller> + <controller type='scsi' index='0' model='virtio-scsi'> + <driver iommu='on'/> + </controller> + <interface type='network'> + <mac address='52:54:00:cc:56:90'/> + <source network='default'/> + <model type='virtio'/> + <driver iommu='on'/> + </interface> + <graphics type='spice' autoport='yes'> + <listen type='address'/> + <gl enable='no'/> + </graphics> + <video> + <model type='qxl'/> + </video> + <memballoon model='virtio'> + <driver iommu='on'/> + </memballoon> + <rng model='virtio'> + <driver iommu='on'/> + </rng> + </devices> + <launchSecurity type='sev'> + <cbitpos>47</cbitpos> + <reducedPhysBits>1</reducedPhysBits> + <policy>0x0003</policy> + </launchSecurity> +</domain></pre> + + <h5>PC-i440fx machine:</h5> + <pre> +<domain type='kvm'> + <name>sev-dummy-legacy</name> + <memory unit='KiB'>4194304</memory> + <currentMemory unit='KiB'>4194304</currentMemory> + <memtune> + <hard_limit unit='KiB'>5242880</hard_limit> + </memtune> + <vcpu placement='static'>4</vcpu> + <os> + <type arch='x86_64' machine='pc-i440fx-3.0'>hvm</type> + <loader readonly='yes' type='pflash'>/usr/share/edk2/ovmf/OVMF_CODE.fd</loader> + <nvram>/var/lib/libvirt/qemu/nvram/sev-dummy_VARS.fd</nvram> + <boot dev='hd'/> + </os> + <features> + <acpi/> + <apic/> + <vmport state='off'/> + </features> + <cpu mode='host-model' check='partial'> + <model fallback='allow'/> + </cpu> + <clock offset='utc'> + <timer name='rtc' tickpolicy='catchup'/> + <timer name='pit' tickpolicy='delay'/> + <timer name='hpet' present='no'/> + </clock> + <on_poweroff>destroy</on_poweroff> + <on_reboot>restart</on_reboot> + <on_crash>destroy</on_crash> + <pm> + <suspend-to-mem enabled='no'/> + <suspend-to-disk enabled='no'/> + </pm> + <devices> + <emulator>/usr/bin/qemu-kvm</emulator> + <disk type='file' device='disk'> + <driver name='qemu' type='qcow2'/> + <source file='/var/lib/libvirt/images/sev-dummy-seabios.qcow2'/> + <target dev='sda' bus='sata'/> + </disk> + <interface type='network'> + <mac address='52:54:00:d8:96:c8'/> + <source network='default'/> + <model type='virtio-non-transitional'/> + </interface> + <serial type='pty'> + <target type='isa-serial' port='0'> + <model name='isa-serial'/> + </target> + </serial> + <console type='pty'> + <target type='serial' port='0'/> + </console> + <input type='tablet' bus='usb'> + <address type='usb' bus='0' port='1'/> + </input> + <input type='mouse' bus='ps2'/> + <input type='keyboard' bus='ps2'/> + <graphics type='spice' autoport='yes'> + <listen type='address'/> + <gl enable='no'/> + </graphics> + <video> + <model type='qxl' ram='65536' vram='65536' vgamem='16384' heads='1' primary='yes'/> + </video> + <memballoon model='virtio-non-transitional'> + <driver iommu='on'/> + </memballoon> + <rng model='virtio-non-transitional'> + <driver iommu='on'/> + </rng> + </devices> + <launchSecurity type='sev'> + <cbitpos>47</cbitpos> + <reducedPhysBits>1</reducedPhysBits> + <policy>0x0003</policy> + </launchSecurity> +</domain></pre> + </body> +</html> -- 2.21.0

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