Mechanical change using gsed, then style manually adapted
to pass checkpatch.pl script.
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20250424194905.82506-4-philmd@linaro.org>
"Host Memory Backends" and "Memory devices" queue ("mem"):
- Fixup handling of virtio-mem unplug during system resets, as
preparation for s390x support (especially kdump in the Linux guest)
- virtio-mem support for s390x
-----BEGIN PGP SIGNATURE-----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=HDxr
-----END PGP SIGNATURE-----
Merge tag 'mem-2024-12-21' of https://github.com/davidhildenbrand/qemu into staging
Hi,
"Host Memory Backends" and "Memory devices" queue ("mem"):
- Fixup handling of virtio-mem unplug during system resets, as
preparation for s390x support (especially kdump in the Linux guest)
- virtio-mem support for s390x
# -----BEGIN PGP SIGNATURE-----
#
# iQJFBAABCAAvFiEEG9nKrXNcTDpGDfzKTd4Q9wD/g1oFAmdnFD4RHGRhdmlkQHJl
# ZGhhdC5jb20ACgkQTd4Q9wD/g1rWBBAAp7WkYaNAjRy1PgpjNZ3z1gUJc/vk+skJ
# xVgGodA8txrJOFpNrbTyfhrdLs2TV4oWDvB/zrZRRtuxvur3O1EhFd9k6EqXuydr
# 0FunvLvVJwRHfEZycjN4aacQMRH3CJw07OaTzexeSl5UR/6w5PRofwUK4HX7W/Ka
# arqomGa3OJrs1+WgkV0Qcn4vh9HLRVv3iNC2Xo4W1wOCr1Du9zSPn9oC7zOQ0EO4
# ZC//7QsdkNRjUX/yMXMkhlSXx3b/RmRg2DBrxo7BZXg27VwGu4uHxL4LRBZiB2A7
# V9MqFOcVKzPMkXKTRjrgZ0vXQx1MPJ6WprEihMzMpYU6DrpA7KN/l8Ca8H24B2ln
# h7+bmkDsHVVcWovE9ii/9cMRfws6uWXXg3KoA8RQ8IbX1tU02lblw2uHhXEzcoge
# npqp/Z5LAiKVMetEnNnLH5thjut5PAEjuqD00cmZAMy4DNngLX2bGSdzMeVBkDMa
# 78ehLGRplm3t7ibUfaZaMKe6UD9tFrcD6XKsvUTXXHNbYO8ynbx58WOxSZmY98zU
# n3JNQRqtXYjBVlH3Dqm47vOTZHgOzFv3raa8BmSLpcBDeTXCTcUIl20s77dGw/vT
# r5YNCMN7O4YPFKUoRK9604QTgw6qlYaRTQlJD09usprGqVylb6gQtfZZuZkYDMp8
# sEI77QHsePA=
# =HDxr
# -----END PGP SIGNATURE-----
# gpg: Signature made Sat 21 Dec 2024 14:17:18 EST
# gpg: using RSA key 1BD9CAAD735C4C3A460DFCCA4DDE10F700FF835A
# gpg: issuer "david@redhat.com"
# gpg: Good signature from "David Hildenbrand <david@redhat.com>" [unknown]
# gpg: aka "David Hildenbrand <davidhildenbrand@gmail.com>" [full]
# gpg: aka "David Hildenbrand <hildenbr@in.tum.de>" [unknown]
# gpg: WARNING: The key's User ID is not certified with a trusted signature!
# gpg: There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 1BD9 CAAD 735C 4C3A 460D FCCA 4DDE 10F7 00FF 835A
* tag 'mem-2024-12-21' of https://github.com/davidhildenbrand/qemu:
s390x: virtio-mem support
s390x/virtio-ccw: add support for virtio based memory devices
s390x: remember the maximum page size
s390x/pv: prepare for memory devices
s390x/s390-virtio-ccw: prepare for memory devices
s390x/s390-skeys: prepare for memory devices
s390x/s390-stattrib-kvm: prepare for memory devices and sparse memory layouts
s390x/s390-hypercall: introduce DIAG500 STORAGE_LIMIT
s390x: introduce s390_get_memory_limit()
s390x/s390-virtio-ccw: move setting the maximum guest size from sclp to machine code
s390x: rename s390-virtio-hcall* to s390-hypercall*
s390x/s390-virtio-hcall: prepare for more diag500 hypercalls
s390x/s390-virtio-hcall: remove hypercall registration mechanism
s390x/s390-virtio-ccw: don't crash on weird RAM sizes
virtio-mem: unplug memory only during system resets, not device resets
Conflicts:
- hw/s390x/s390-stattrib-kvm.c
sysemu/ -> system/ header rename conflict.
- hw/s390x/virtio-ccw-mem.c
Make Property array const and removed DEFINE_PROP_END_OF_LIST() to
conform to the latest conventions.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Let's add our virtio-mem-ccw proxy device and wire it up. We should
be supporting everything (e.g., device unplug, "dynamic-memslots") that
we already support for the virtio-pci variant.
With a Linux guest that supports virtio-mem (and has automatic memory
onlining properly configured) the following example will work:
1. Start a VM with 4G initial memory and a virtio-mem device with a maximum
capacity of 16GB:
qemu/build/qemu-system-s390x \
--enable-kvm \
-m 4G,maxmem=20G \
-nographic \
-smp 8 \
-hda Fedora-Server-KVM-40-1.14.s390x.qcow2 \
-chardev socket,id=monitor,path=/var/tmp/monitor,server,nowait \
-mon chardev=monitor,mode=readline \
-object memory-backend-ram,id=mem0,size=16G,reserve=off \
-device virtio-mem-ccw,id=vmem0,memdev=mem0,dynamic-memslots=on
2. Query the current size of virtio-mem device:
(qemu) info memory-devices
Memory device [virtio-mem]: "vmem0"
memaddr: 0x100000000
node: 0
requested-size: 0
size: 0
max-size: 17179869184
block-size: 1048576
memdev: /objects/mem0
3. Request to grow it to 8GB (hotplug 8GB):
(qemu) qom-set vmem0 requested-size 8G
(qemu) info memory-devices
Memory device [virtio-mem]: "vmem0"
memaddr: 0x100000000
node: 0
requested-size: 8589934592
size: 8589934592
max-size: 17179869184
block-size: 1048576
memdev: /objects/mem0
4. Request to grow to 16GB (hotplug another 8GB):
(qemu) qom-set vmem0 requested-size 16G
(qemu) info memory-devices
Memory device [virtio-mem]: "vmem0"
memaddr: 0x100000000
node: 0
requested-size: 17179869184
size: 17179869184
max-size: 17179869184
block-size: 1048576
memdev: /objects/mem0
5. Try to hotunplug all memory again, shrinking to 0GB:
(qemu) qom-set vmem0 requested-size 0G
(qemu) info memory-devices
Memory device [virtio-mem]: "vmem0"
memaddr: 0x100000000
node: 0
requested-size: 0
size: 0
max-size: 17179869184
block-size: 1048576
memdev: /objects/mem0
6. If it worked, unplug the device
(qemu) device_del vmem0
(qemu) info memory-devices
(qemu) object_del mem0
7. Hotplug a new device with a smaller capacity and directly size it to 1GB
(qemu) object_add memory-backend-ram,id=mem0,size=8G,reserve=off
(qemu) device_add virtio-mem-ccw,id=vmem0,memdev=mem0,\
dynamic-memslots=on,requested-size=1G
(qemu) info memory-devices
Memory device [virtio-mem]: "vmem0"
memaddr: 0x100000000
node: 0
requested-size: 1073741824
size: 1073741824
max-size: 8589934592
block-size: 1048576
memdev: /objects/mem0
Trying to use a virtio-mem device backed by hugetlb into a !hugetlb VM
correctly results in the error:
... Memory device uses a bigger page size than initial memory
Note that the virtio-mem driver in Linux will supports 1 MiB (pageblock)
granularity.
Message-ID: <20241219144115.2820241-15-david@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
