56 lines
2.5 KiB
Diff
56 lines
2.5 KiB
Diff
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From a6f8ccba4b55a1f3715a0fd3d8f611b954e443a5 Mon Sep 17 00:00:00 2001
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From: David Hildenbrand <david@redhat.com>
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Date: Thu, 18 Mar 2021 10:41:49 +0100
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Subject: [PATCH] feat(qemu): include the virtio_mem kernel module
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This adds support for virtio-mem devices, which provide a dynamic
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amount of memory in a VM. Right now, the driver gets loaded and any
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memory gets added to the system when loading the kernel module from disk.
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While not strictly required to boot, we want to be able to
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1) add virito-mem provided memory to the system early while booting up
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2) add virtio-mem provided memory even when booting without a disk
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3) add virtio-mem devices without adding actual memory in kdump
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environments such that we can query things like:
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a) is a certain PFN currently plugged in the hypervisor and, therefore,
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should actually be read when creating a system dump. (kexec-tools
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prepares the vmcore header, like on x86-64)
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b) which ranges of a virtio-mem device are currently plugged in the
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hypervisor and, therefore, should be added to the dump. (vmcore header
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gets prepared by the crashkernel, like on s390x)
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Note that loading virtio-mem in kdump environments currently fails with
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-EBUSY -- but there are plans to install proper hooks instead to support
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especially a) in the near future.
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1) and 2) are only really effective when memory hotplug is configured to
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automatically online all added system RAM in the kernel (and not late,
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via udev rules): e.g., via "mhp_default_state=online" on the kernel
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cmdline or via CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE in the kernel.
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Especially 2) and 3) require the module to be present inside the initial
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ramdisk. The primary use case for including it in the initial ramdisk
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is 3).
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Signed-off-by: David Hildenbrand <david@redhat.com>
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(cherry picked from commit f3dcb60619671f2d353caaa42d38207172c8b3ba)
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Cherry-picked from: f3dcb60619671f2d353caaa42d38207172c8b3ba
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Resolves: #2228422
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---
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modules.d/90qemu/module-setup.sh | 2 +-
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1 file changed, 1 insertion(+), 1 deletion(-)
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diff --git a/modules.d/90qemu/module-setup.sh b/modules.d/90qemu/module-setup.sh
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index 7e5ea6a4..e89dafbb 100755
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--- a/modules.d/90qemu/module-setup.sh
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+++ b/modules.d/90qemu/module-setup.sh
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@@ -31,7 +31,7 @@ installkernel() {
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hostonly='' instmods \
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ata_piix ata_generic pata_acpi cdrom sr_mod ahci \
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virtio_blk virtio virtio_ring virtio_pci \
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- virtio_scsi virtio_console virtio_rng \
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+ virtio_scsi virtio_console virtio_rng virtio_mem \
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spapr-vscsi \
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qemu_fw_cfg
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}
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