On 10/7/20 5:01 AM, Michal Privoznik wrote:

In 88957116c9 I've switched to -machine memory-backend=ID and -object memory-backend-* because QEMU is obsoleting -mem-path and -mem-prealloc. However, what I did not foresee was that using -machine memory-backend in combination with -numa is not allowed in QEMU. This was reported upstream and fortunately not released yet.

The problem is that if domain has NUMA nodes then we will generate memory-backend-* objects for NUMA nodes (because if QEMU is new enough to expose default RAM ID it also supports -numa memdev=) and adding non-NUMA memory backend is wrong.

Reported-by: Masayoshi Mizuma <msys.mizuma@gmail.com> Signed-off-by: Michal Privoznik <mprivozn@redhat.com> --- src/qemu/qemu_command.c | 32 +++++++++++++++---- .../hugepages-nvdimm.x86_64-latest.args | 6 +--- ...memory-default-hugepage.x86_64-latest.args | 5 +-- .../memfd-memory-numa.x86_64-latest.args | 5 +-- ...y-hotplug-nvdimm-access.x86_64-latest.args | 4 +-- ...ry-hotplug-nvdimm-align.x86_64-latest.args | 4 +-- ...ry-hotplug-nvdimm-label.x86_64-latest.args | 4 +-- ...ory-hotplug-nvdimm-pmem.x86_64-latest.args | 4 +-- ...hotplug-nvdimm-readonly.x86_64-latest.args | 4 +-- .../memory-hotplug-nvdimm.x86_64-latest.args | 4 +-- .../numatune-hmat.x86_64-latest.args | 4 +-- ...vhost-user-fs-fd-memory.x86_64-latest.args | 4 +-- ...vhost-user-fs-hugepages.x86_64-latest.args | 5 +-- ...host-user-gpu-secondary.x86_64-latest.args | 3 +- .../vhost-user-vga.x86_64-latest.args | 3 +- 15 files changed, 39 insertions(+), 52 deletions(-)

diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c index 476cf6972e..c347f80f08 100644 --- a/src/qemu/qemu_command.c +++ b/src/qemu/qemu_command.c @@ -6829,7 +6829,6 @@ qemuBuildMachineCommandLine(virCommandPtr cmd, virTristateSwitch vmport = def->features[VIR_DOMAIN_FEATURE_VMPORT]; virTristateSwitch smm = def->features[VIR_DOMAIN_FEATURE_SMM]; virCPUDefPtr cpu = def->cpu; - const char *defaultRAMid = NULL; g_auto(virBuffer) buf = VIR_BUFFER_INITIALIZER; size_t i;

@@ -7046,11 +7045,24 @@ qemuBuildMachineCommandLine(virCommandPtr cmd, if (virDomainNumaHasHMAT(def->numa)) virBufferAddLit(&buf, ",hmat=on");

- defaultRAMid = virQEMUCapsGetMachineDefaultRAMid(qemuCaps, - def->virtType, - def->os.machine); - if (defaultRAMid) - virBufferAsprintf(&buf, ",memory-backend=%s", defaultRAMid); + if (!virDomainNumaGetNodeCount(def->numa)) { + const char *defaultRAMid = NULL; + + /* QEMU is obsoleting -mem-path and -mem-prealloc. That means we have + * to switch to memory-backend-* even for regular RAM and to keep + * domain migratable we have to set the same ID as older QEMUs would. + * If domain has no NUMA nodes and QEMU is new enough to expose ID of + * the default RAM we want to use it for default RAM (construct + * memory-backend-* with corresponding attributes instead of obsolete + * -mem-path and -mem-prealloc.

I think you're missing a closing ')' in this sentence up here ^ Everything else LGTM. Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>

+ * This generates only reference for the memory-backend-* object added + * later in qemuBuildMemCommandLine() */ + defaultRAMid = virQEMUCapsGetMachineDefaultRAMid(qemuCaps, + def->virtType, + def->os.machine); + if (defaultRAMid) + virBufferAsprintf(&buf, ",memory-backend=%s", defaultRAMid); + }

virCommandAddArgBuffer(cmd, &buf);

@@ -7216,7 +7228,13 @@ qemuBuildMemCommandLine(virCommandPtr cmd, def->os.machine);

if (defaultRAMid) { - qemuBuildMemCommandLineMemoryDefaultBackend(cmd, def, priv, defaultRAMid); + /* As documented in qemuBuildMachineCommandLine() if QEMU is new enough + * to expose default RAM ID we must use memory-backend-* even for + * regular memory because -mem-path and -mem-prealloc are obsolete. + * However, if domain has one or more NUMA nodes then there is no + * default RAM and we mustn't generate the memory object. */ + if (!virDomainNumaGetNodeCount(def->numa)) + qemuBuildMemCommandLineMemoryDefaultBackend(cmd, def, priv, defaultRAMid); } else { if (def->mem.allocation == VIR_DOMAIN_MEMORY_ALLOCATION_IMMEDIATE) { virCommandAddArgList(cmd, "-mem-prealloc", NULL); diff --git a/tests/qemuxml2argvdata/hugepages-nvdimm.x86_64-latest.args b/tests/qemuxml2argvdata/hugepages-nvdimm.x86_64-latest.args index 192b033e9e..969bb713b5 100644 --- a/tests/qemuxml2argvdata/hugepages-nvdimm.x86_64-latest.args +++ b/tests/qemuxml2argvdata/hugepages-nvdimm.x86_64-latest.args @@ -12,13 +12,9 @@ QEMU_AUDIO_DRV=none \ -S \ -object secret,id=masterKey0,format=raw,\ file=/tmp/lib/domain--1-QEMUGuest1/master-key.aes \ --machine pc,accel=tcg,usb=off,dump-guest-core=off,nvdimm=on,\ -memory-backend=pc.ram \ +-machine pc,accel=tcg,usb=off,dump-guest-core=off,nvdimm=on \ -cpu qemu64 \ -m size=1048576k,slots=16,maxmem=1099511627776k \ --object memory-backend-file,id=pc.ram,\ -mem-path=/dev/hugepages2M/libvirt/qemu/-1-QEMUGuest1,share=yes,prealloc=yes,\ -size=1073741824 \ -overcommit mem-lock=off \ -smp 2,sockets=2,dies=1,cores=1,threads=1 \ -object memory-backend-file,id=ram-node0,\ diff --git a/tests/qemuxml2argvdata/memfd-memory-default-hugepage.x86_64-latest.args b/tests/qemuxml2argvdata/memfd-memory-default-hugepage.x86_64-latest.args index b43e7d9c3c..ef15e2e97e 100644 --- a/tests/qemuxml2argvdata/memfd-memory-default-hugepage.x86_64-latest.args +++ b/tests/qemuxml2argvdata/memfd-memory-default-hugepage.x86_64-latest.args @@ -12,12 +12,9 @@ QEMU_AUDIO_DRV=none \ -S \ -object secret,id=masterKey0,format=raw,\ file=/tmp/lib/domain--1-instance-00000092/master-key.aes \ --machine pc-i440fx-2.3,accel=kvm,usb=off,dump-guest-core=off,\ -memory-backend=pc.ram \ +-machine pc-i440fx-2.3,accel=kvm,usb=off,dump-guest-core=off \ -cpu qemu64 \ -m 14336 \ --object memory-backend-memfd,id=pc.ram,hugetlb=yes,hugetlbsize=2097152,\ -share=yes,prealloc=yes,size=15032385536 \ -overcommit mem-lock=off \ -smp 8,sockets=1,dies=1,cores=8,threads=1 \ -object memory-backend-memfd,id=ram-node0,hugetlb=yes,hugetlbsize=2097152,\ diff --git a/tests/qemuxml2argvdata/memfd-memory-numa.x86_64-latest.args b/tests/qemuxml2argvdata/memfd-memory-numa.x86_64-latest.args index b43e7d9c3c..ef15e2e97e 100644 --- a/tests/qemuxml2argvdata/memfd-memory-numa.x86_64-latest.args +++ b/tests/qemuxml2argvdata/memfd-memory-numa.x86_64-latest.args @@ -12,12 +12,9 @@ QEMU_AUDIO_DRV=none \ -S \ -object secret,id=masterKey0,format=raw,\ file=/tmp/lib/domain--1-instance-00000092/master-key.aes \ --machine pc-i440fx-2.3,accel=kvm,usb=off,dump-guest-core=off,\ -memory-backend=pc.ram \ +-machine pc-i440fx-2.3,accel=kvm,usb=off,dump-guest-core=off \ -cpu qemu64 \ -m 14336 \ --object memory-backend-memfd,id=pc.ram,hugetlb=yes,hugetlbsize=2097152,\ -share=yes,prealloc=yes,size=15032385536 \ -overcommit mem-lock=off \ -smp 8,sockets=1,dies=1,cores=8,threads=1 \ -object memory-backend-memfd,id=ram-node0,hugetlb=yes,hugetlbsize=2097152,\ diff --git a/tests/qemuxml2argvdata/memory-hotplug-nvdimm-access.x86_64-latest.args b/tests/qemuxml2argvdata/memory-hotplug-nvdimm-access.x86_64-latest.args index c5c5befdd5..8d3fa2e867 100644 --- a/tests/qemuxml2argvdata/memory-hotplug-nvdimm-access.x86_64-latest.args +++ b/tests/qemuxml2argvdata/memory-hotplug-nvdimm-access.x86_64-latest.args @@ -12,11 +12,9 @@ QEMU_AUDIO_DRV=none \ -S \ -object secret,id=masterKey0,format=raw,\ file=/tmp/lib/domain--1-QEMUGuest1/master-key.aes \ --machine pc,accel=tcg,usb=off,dump-guest-core=off,nvdimm=on,\ -memory-backend=pc.ram \ +-machine pc,accel=tcg,usb=off,dump-guest-core=off,nvdimm=on \ -cpu qemu64 \ -m size=219136k,slots=16,maxmem=1099511627776k \ --object memory-backend-ram,id=pc.ram,size=224395264 \ -overcommit mem-lock=off \ -smp 2,sockets=2,dies=1,cores=1,threads=1 \ -object memory-backend-ram,id=ram-node0,size=224395264 \ diff --git a/tests/qemuxml2argvdata/memory-hotplug-nvdimm-align.x86_64-latest.args b/tests/qemuxml2argvdata/memory-hotplug-nvdimm-align.x86_64-latest.args index 418bf1158d..4f22f78277 100644 --- a/tests/qemuxml2argvdata/memory-hotplug-nvdimm-align.x86_64-latest.args +++ b/tests/qemuxml2argvdata/memory-hotplug-nvdimm-align.x86_64-latest.args @@ -12,11 +12,9 @@ QEMU_AUDIO_DRV=none \ -S \ -object secret,id=masterKey0,format=raw,\ file=/tmp/lib/domain--1-QEMUGuest1/master-key.aes \ --machine pc,accel=tcg,usb=off,dump-guest-core=off,nvdimm=on,\ -memory-backend=pc.ram \ +-machine pc,accel=tcg,usb=off,dump-guest-core=off,nvdimm=on \ -cpu qemu64 \ -m size=219136k,slots=16,maxmem=1099511627776k \ --object memory-backend-ram,id=pc.ram,size=224395264 \ -overcommit mem-lock=off \ -smp 2,sockets=2,dies=1,cores=1,threads=1 \ -object memory-backend-ram,id=ram-node0,size=224395264 \ diff --git a/tests/qemuxml2argvdata/memory-hotplug-nvdimm-label.x86_64-latest.args b/tests/qemuxml2argvdata/memory-hotplug-nvdimm-label.x86_64-latest.args index 66477a2b09..53dda234a2 100644 --- a/tests/qemuxml2argvdata/memory-hotplug-nvdimm-label.x86_64-latest.args +++ b/tests/qemuxml2argvdata/memory-hotplug-nvdimm-label.x86_64-latest.args @@ -12,11 +12,9 @@ QEMU_AUDIO_DRV=none \ -S \ -object secret,id=masterKey0,format=raw,\ file=/tmp/lib/domain--1-QEMUGuest1/master-key.aes \ --machine pc,accel=tcg,usb=off,dump-guest-core=off,nvdimm=on,\ -memory-backend=pc.ram \ +-machine pc,accel=tcg,usb=off,dump-guest-core=off,nvdimm=on \ -cpu qemu64 \ -m size=219136k,slots=16,maxmem=1099511627776k \ --object memory-backend-ram,id=pc.ram,size=224395264 \ -overcommit mem-lock=off \ -smp 2,sockets=2,dies=1,cores=1,threads=1 \ -object memory-backend-ram,id=ram-node0,size=224395264 \ diff --git a/tests/qemuxml2argvdata/memory-hotplug-nvdimm-pmem.x86_64-latest.args b/tests/qemuxml2argvdata/memory-hotplug-nvdimm-pmem.x86_64-latest.args index 759d749c2e..cac02a6f6d 100644 --- a/tests/qemuxml2argvdata/memory-hotplug-nvdimm-pmem.x86_64-latest.args +++ b/tests/qemuxml2argvdata/memory-hotplug-nvdimm-pmem.x86_64-latest.args @@ -12,11 +12,9 @@ QEMU_AUDIO_DRV=none \ -S \ -object secret,id=masterKey0,format=raw,\ file=/tmp/lib/domain--1-QEMUGuest1/master-key.aes \ --machine pc,accel=tcg,usb=off,dump-guest-core=off,nvdimm=on,\ -memory-backend=pc.ram \ +-machine pc,accel=tcg,usb=off,dump-guest-core=off,nvdimm=on \ -cpu qemu64 \ -m size=219136k,slots=16,maxmem=1099511627776k \ --object memory-backend-ram,id=pc.ram,size=224395264 \ -overcommit mem-lock=off \ -smp 2,sockets=2,dies=1,cores=1,threads=1 \ -object memory-backend-ram,id=ram-node0,size=224395264 \ diff --git a/tests/qemuxml2argvdata/memory-hotplug-nvdimm-readonly.x86_64-latest.args b/tests/qemuxml2argvdata/memory-hotplug-nvdimm-readonly.x86_64-latest.args index b195b8625c..5e44496e39 100644 --- a/tests/qemuxml2argvdata/memory-hotplug-nvdimm-readonly.x86_64-latest.args +++ b/tests/qemuxml2argvdata/memory-hotplug-nvdimm-readonly.x86_64-latest.args @@ -12,11 +12,9 @@ QEMU_AUDIO_DRV=none \ -S \ -object secret,id=masterKey0,format=raw,\ file=/tmp/lib/domain--1-QEMUGuest1/master-key.aes \ --machine pc,accel=tcg,usb=off,dump-guest-core=off,nvdimm=on,\ -memory-backend=pc.ram \ +-machine pc,accel=tcg,usb=off,dump-guest-core=off,nvdimm=on \ -cpu qemu64 \ -m size=219136k,slots=16,maxmem=1099511627776k \ --object memory-backend-ram,id=pc.ram,size=224395264 \ -overcommit mem-lock=off \ -smp 2,sockets=2,dies=1,cores=1,threads=1 \ -object memory-backend-ram,id=ram-node0,size=224395264 \ diff --git a/tests/qemuxml2argvdata/memory-hotplug-nvdimm.x86_64-latest.args b/tests/qemuxml2argvdata/memory-hotplug-nvdimm.x86_64-latest.args index ae416d7c7f..94f8444d95 100644 --- a/tests/qemuxml2argvdata/memory-hotplug-nvdimm.x86_64-latest.args +++ b/tests/qemuxml2argvdata/memory-hotplug-nvdimm.x86_64-latest.args @@ -12,11 +12,9 @@ QEMU_AUDIO_DRV=none \ -S \ -object secret,id=masterKey0,format=raw,\ file=/tmp/lib/domain--1-QEMUGuest1/master-key.aes \ --machine pc,accel=tcg,usb=off,dump-guest-core=off,nvdimm=on,\ -memory-backend=pc.ram \ +-machine pc,accel=tcg,usb=off,dump-guest-core=off,nvdimm=on \ -cpu qemu64 \ -m size=1048576k,slots=16,maxmem=1099511627776k \ --object memory-backend-ram,id=pc.ram,size=1073741824 \ -overcommit mem-lock=off \ -smp 2,sockets=2,dies=1,cores=1,threads=1 \ -object memory-backend-ram,id=ram-node0,size=1073741824 \ diff --git a/tests/qemuxml2argvdata/numatune-hmat.x86_64-latest.args b/tests/qemuxml2argvdata/numatune-hmat.x86_64-latest.args index be4a9ed871..c52015caa8 100644 --- a/tests/qemuxml2argvdata/numatune-hmat.x86_64-latest.args +++ b/tests/qemuxml2argvdata/numatune-hmat.x86_64-latest.args @@ -12,11 +12,9 @@ QEMU_AUDIO_DRV=none \ -S \ -object secret,id=masterKey0,format=raw,\ file=/tmp/lib/domain--1-QEMUGuest/master-key.aes \ --machine pc,accel=tcg,usb=off,dump-guest-core=off,hmat=on,\ -memory-backend=pc.ram \ +-machine pc,accel=tcg,usb=off,dump-guest-core=off,hmat=on \ -cpu qemu64 \ -m 12288 \ --object memory-backend-ram,id=pc.ram,size=12884901888 \ -overcommit mem-lock=off \ -smp 12,sockets=12,cores=1,threads=1 \ -object memory-backend-ram,id=ram-node0,size=2147483648 \ diff --git a/tests/qemuxml2argvdata/vhost-user-fs-fd-memory.x86_64-latest.args b/tests/qemuxml2argvdata/vhost-user-fs-fd-memory.x86_64-latest.args index 13359c91fe..dd5f68abc5 100644 --- a/tests/qemuxml2argvdata/vhost-user-fs-fd-memory.x86_64-latest.args +++ b/tests/qemuxml2argvdata/vhost-user-fs-fd-memory.x86_64-latest.args @@ -12,11 +12,9 @@ QEMU_AUDIO_DRV=none \ -S \ -object secret,id=masterKey0,format=raw,\ file=/tmp/lib/domain--1-guest/master-key.aes \ --machine pc,accel=kvm,usb=off,dump-guest-core=off,memory-backend=pc.ram \ +-machine pc,accel=kvm,usb=off,dump-guest-core=off \ -cpu qemu64 \ -m 14336 \ --object memory-backend-file,id=pc.ram,\ -mem-path=/var/lib/libvirt/qemu/ram/-1-guest/pc.ram,share=yes,size=15032385536 \ -overcommit mem-lock=off \ -smp 2,sockets=2,cores=1,threads=1 \ -object memory-backend-file,id=ram-node0,\ diff --git a/tests/qemuxml2argvdata/vhost-user-fs-hugepages.x86_64-latest.args b/tests/qemuxml2argvdata/vhost-user-fs-hugepages.x86_64-latest.args index 59f45d466b..e4f5db7a63 100644 --- a/tests/qemuxml2argvdata/vhost-user-fs-hugepages.x86_64-latest.args +++ b/tests/qemuxml2argvdata/vhost-user-fs-hugepages.x86_64-latest.args @@ -12,12 +12,9 @@ QEMU_AUDIO_DRV=none \ -S \ -object secret,id=masterKey0,format=raw,\ file=/tmp/lib/domain--1-guest/master-key.aes \ --machine q35,accel=tcg,usb=off,dump-guest-core=off,memory-backend=pc.ram \ +-machine q35,accel=tcg,usb=off,dump-guest-core=off \ -cpu qemu64 \ -m 2048 \ --object memory-backend-file,id=pc.ram,\ -mem-path=/dev/hugepages2M/libvirt/qemu/-1-guest,share=yes,prealloc=yes,\ -size=2147483648 \ -overcommit mem-lock=off \ -smp 2,sockets=2,cores=1,threads=1 \ -object memory-backend-file,id=ram-node0,\ diff --git a/tests/qemuxml2argvdata/vhost-user-gpu-secondary.x86_64-latest.args b/tests/qemuxml2argvdata/vhost-user-gpu-secondary.x86_64-latest.args index e7d3315b8f..e99a5342dc 100644 --- a/tests/qemuxml2argvdata/vhost-user-gpu-secondary.x86_64-latest.args +++ b/tests/qemuxml2argvdata/vhost-user-gpu-secondary.x86_64-latest.args @@ -12,10 +12,9 @@ QEMU_AUDIO_DRV=none \ -S \ -object secret,id=masterKey0,format=raw,\ file=/tmp/lib/domain--1-QEMUGuest1/master-key.aes \ --machine pc,accel=tcg,usb=off,dump-guest-core=off,memory-backend=pc.ram \ +-machine pc,accel=tcg,usb=off,dump-guest-core=off \ -cpu qemu64 \ -m 214 \ --object memory-backend-memfd,id=pc.ram,share=yes,size=224395264 \ -overcommit mem-lock=off \ -smp 1,sockets=1,cores=1,threads=1 \ -object memory-backend-memfd,id=ram-node0,share=yes,size=224395264 \ diff --git a/tests/qemuxml2argvdata/vhost-user-vga.x86_64-latest.args b/tests/qemuxml2argvdata/vhost-user-vga.x86_64-latest.args index df5b1b481d..277bf8c646 100644 --- a/tests/qemuxml2argvdata/vhost-user-vga.x86_64-latest.args +++ b/tests/qemuxml2argvdata/vhost-user-vga.x86_64-latest.args @@ -12,10 +12,9 @@ QEMU_AUDIO_DRV=none \ -S \ -object secret,id=masterKey0,format=raw,\ file=/tmp/lib/domain--1-QEMUGuest1/master-key.aes \ --machine pc,accel=tcg,usb=off,dump-guest-core=off,memory-backend=pc.ram \ +-machine pc,accel=tcg,usb=off,dump-guest-core=off \ -cpu qemu64 \ -m 214 \ --object memory-backend-memfd,id=pc.ram,share=yes,size=224395264 \ -overcommit mem-lock=off \ -smp 1,sockets=1,cores=1,threads=1 \ -object memory-backend-memfd,id=ram-node0,share=yes,size=224395264 \