similar to: [RFC] virtio-mem: paravirtualized memory

Long time no RFC! I finally had time to get the next version of the Linux driver side of virtio-mem into shape, incorporating ideas and feedback from previous discussions. This RFC is based on the series currently on the mm list: - [PATCH 0/3] Remove __online_page_set_limits() - [PATCH v1 0/3] mm/memory_hotplug: Export generic_online_page() - [PATCH v4 0/8] mm/memory_hotplug: Shrink zones before

This series is based on latest linux-next. The patches are located at: https://github.com/davidhildenbrand/linux.git virtio-mem-v1 The basic idea of virtio-mem is to provide a flexible, cross-architecture memory hot(un)plug solution that avoids many limitations imposed by existing technologies, architectures, and interfaces. More details can be found below and in linked material. It's

This series is based on latest linux-next. The patches are located at: https://github.com/davidhildenbrand/linux.git virtio-mem-v1 The basic idea of virtio-mem is to provide a flexible, cross-architecture memory hot(un)plug solution that avoids many limitations imposed by existing technologies, architectures, and interfaces. More details can be found below and in linked material. It's

This series is based on latest linux-next. The patches are located at: https://github.com/davidhildenbrand/linux.git virtio-mem-rfc-v4 The basic idea of virtio-mem is to provide a flexible, cross-architecture memory hot(un)plug solution that avoids many limitations imposed by existing technologies, architectures, and interfaces. More details can be found below and in linked material. This

This series is based on latest linux-next. The patches are located at: https://github.com/davidhildenbrand/linux.git virtio-mem-rfc-v4 The basic idea of virtio-mem is to provide a flexible, cross-architecture memory hot(un)plug solution that avoids many limitations imposed by existing technologies, architectures, and interfaces. More details can be found below and in linked material. This

This series is based on latest linux-next. The patches are located at: https://github.com/davidhildenbrand/linux.git virtio-mem-v2 I now have acks for all !virtio-mem changes. I'll be happy to get review feedback, testing reports, etc. for the virtio-mem changes. If there are no further comments, I guess this is good to go as a v1 soon. The basic idea of virtio-mem is to provide a

Btw, I am thinking about the following addition to the concept: 1. Add a type to each virtio-mem device. This describes the type of the memory region we expose to the guest. Initially, we could have RAM and RAM_HUGE. The latter one would be interesting, because the guest would know that this memory is based on huge pages in case we would ever want to expose different RAM types to a guest (the

In case we have to migrate a ballon page to a newpage of another zone, the managed page count of both zones is wrong. Paired with memory offlining (which will adjust the managed page count), we can trigger kernel crashes and all kinds of different symptoms. One way to reproduce: 1. Start a QEMU guest with 4GB, no NUMA 2. Hotplug a 1GB DIMM and only the memory to ZONE_NORMAL 3. Inflate the balloon

In case we have to migrate a ballon page to a newpage of another zone, the managed page count of both zones is wrong. Paired with memory offlining (which will adjust the managed page count), we can trigger kernel crashes and all kinds of different symptoms. One way to reproduce: 1. Start a QEMU guest with 4GB, no NUMA 2. Hotplug a 1GB DIMM and only the memory to ZONE_NORMAL 3. Inflate the balloon

This series is based on latest linux-next. The patches are located at: https://github.com/davidhildenbrand/linux.git virtio-mem-v3 Patch #1 - #10 where contained in v2 and only contain minor modifications (mostly smaller fixes). The remaining patches are new and contain smaller optimizations. Details about virtio-mem can be found in the cover letter of v2 [1]. A basic QEMU implementation was

This series is based on latest linux-next. The patches are located at: https://github.com/davidhildenbrand/linux.git virtio-mem-v3 Patch #1 - #10 where contained in v2 and only contain minor modifications (mostly smaller fixes). The remaining patches are new and contain smaller optimizations. Details about virtio-mem can be found in the cover letter of v2 [1]. A basic QEMU implementation was

In case we have to migrate a ballon page to a newpage of another zone, the managed page count of both zones is wrong. Paired with memory offlining (which will adjust the managed page count), we can trigger kernel crashes and all kinds of different symptoms. One way to reproduce: 1. Start a QEMU guest with 4GB, no NUMA 2. Hotplug a 1GB DIMM and only the memory to ZONE_NORMAL 3. Inflate the balloon

In case we have to migrate a ballon page to a newpage of another zone, the managed page count of both zones is wrong. Paired with memory offlining (which will adjust the managed page count), we can trigger kernel crashes and all kinds of different symptoms. One way to reproduce: 1. Start a QEMU guest with 4GB, no NUMA 2. Hotplug a 1GB DIMM and only the memory to ZONE_NORMAL 3. Inflate the balloon

This series is based on v5.7-rc4. The patches are located at: https://github.com/davidhildenbrand/linux.git virtio-mem-v4 This is basically a resend of v3 [1], now based on v5.7-rc4 and restested. One patch was reshuffled and two ACKs I missed to add were added. The rebase did not require any modifications to patches. Details about virtio-mem can be found in the cover letter of v2 [2]. A

Hi guys, despite reading hours and hours in the internet i'm still struggling with "memory", "currentmemory" and "maxMemory". Maybe you can help me to sort it out. My idea is that a guest has an initial value of memory (which "memory" seems to be) when booting. We have some Windows 10 guests which calculate some stuff and i would like to increase

On Tue, Dec 10, 2019 at 02:44:38PM +0100, David Hildenbrand wrote: > On 05.12.19 10:24, David Hildenbrand wrote: > > In case we have to migrate a ballon page to a newpage of another zone, the > > managed page count of both zones is wrong. Paired with memory offlining > > (which will adjust the managed page count), we can trigger kernel crashes > > and all kinds of

In case we have to migrate a ballon page to a newpage of another zone, the managed page count of both zones is wrong. Paired with memory offlining (which will adjust the managed page count), we can trigger kernel crashes and all kinds of different symptoms. One way to reproduce: 1. Start a QEMU guest with 4GB, no NUMA 2. Hotplug a 1GB DIMM and online the memory to ZONE_NORMAL 3. Inflate the

On 23.05.2018 20:24, David Hildenbrand wrote: > This is the Linux driver side of virtio-mem. Compared to the QEMU side, > it is in a pretty complete and clean state. > > virtio-mem is a paravirtualized mechanism of adding/removing memory to/from > a VM. We can do this on a 4MB granularity right now. In Linux, all > memory is added to the ZONE_NORMAL, so unplugging cannot be

On 16.06.2017 17:04, Michael S. Tsirkin wrote: > On Fri, Jun 16, 2017 at 04:20:02PM +0200, David Hildenbrand wrote: >> Hi, >> >> this is an idea that is based on Andrea Arcangeli's original idea to >> host enforce guest access to memory given up using virtio-balloon using >> userfaultfd in the hypervisor. While looking into the details, I >> realized that

On 16.06.2017 17:04, Michael S. Tsirkin wrote: > On Fri, Jun 16, 2017 at 04:20:02PM +0200, David Hildenbrand wrote: >> Hi, >> >> this is an idea that is based on Andrea Arcangeli's original idea to >> host enforce guest access to memory given up using virtio-balloon using >> userfaultfd in the hypervisor. While looking into the details, I >> realized that