similar to: [PATCH v1] virtio-mem: add memory via add_memory_driver_managed()

virtio-mem: add memory via add_memory_driver_managed() On Thu, Jun 11, 2020 at 11:35:18AM +0200, David Hildenbrand wrote: > Virtio-mem managed memory is always detected and added by the virtio-mem > driver, never using something like the firmware-provided memory map. > This is the case after an ordinary system reboot, and has to be guaranteed > after kexec. Especially, virtio-mem

Some add_memory*() users add memory in small, contiguous memory blocks. Examples include virtio-mem, hyper-v balloon, and the XEN balloon. This can quickly result in a lot of memory resources, whereby the actual resource boundaries are not of interest (e.g., it might be relevant for DIMMs, exposed via /proc/iomem to user space). We really want to merge added resources in this scenario where

virtio-mem adds memory in memory block granularity, to be able to remove it in the same granularity again later, and to grow slowly on demand. This, however, results in quite a lot of resources when adding a lot of memory. Resources are effectively stored in a list-based tree. Having a lot of resources not only wastes memory, it also makes traversing that tree more expensive, and makes /proc/iomem

Some add_memory*() users add memory in small, contiguous memory blocks. Examples include virtio-mem, hyper-v balloon, and the XEN balloon. This can quickly result in a lot of memory resources, whereby the actual resource boundaries are not of interest (e.g., it might be relevant for DIMMs, exposed via /proc/iomem to user space). We really want to merge added resources in this scenario where

Some add_memory*() users add memory in small, contiguous memory blocks. Examples include virtio-mem, hyper-v balloon, and the XEN balloon. This can quickly result in a lot of memory resources, whereby the actual resource boundaries are not of interest (e.g., it might be relevant for DIMMs, exposed via /proc/iomem to user space). We really want to merge added resources in this scenario where

Some add_memory*() users add memory in small, contiguous memory blocks. Examples include virtio-mem, hyper-v balloon, and the XEN balloon. This can quickly result in a lot of memory resources, whereby the actual resource boundaries are not of interest (e.g., it might be relevant for DIMMs, exposed via /proc/iomem to user space). We really want to merge added resources in this scenario where

Some add_memory*() users add memory in small, contiguous memory blocks. Examples include virtio-mem, hyper-v balloon, and the XEN balloon. This can quickly result in a lot of memory resources, whereby the actual resource boundaries are not of interest (e.g., it might be relevant for DIMMs, exposed via /proc/iomem to user space). We really want to merge added resources in this scenario where

Some add_memory*() users add memory in small, contiguous memory blocks. Examples include virtio-mem, hyper-v balloon, and the XEN balloon. This can quickly result in a lot of memory resources, whereby the actual resource boundaries are not of interest (e.g., it might be relevant for DIMMs, exposed via /proc/iomem to user space). We really want to merge added resources in this scenario where

We soon want to pass flags, e.g., to mark added System RAM resources. mergeable. Prepare for that. This patch is based on a similar patch by Oscar Salvador: https://lkml.kernel.org/r/20190625075227.15193-3-osalvador at suse.de Acked-by: Wei Liu <wei.liu at kernel.org> Cc: Andrew Morton <akpm at linux-foundation.org> Cc: Michal Hocko <mhocko at suse.com> Cc: Dan Williams

We soon want to pass flags, e.g., to mark added System RAM resources. mergeable. Prepare for that. This patch is based on a similar patch by Oscar Salvador: https://lkml.kernel.org/r/20190625075227.15193-3-osalvador at suse.de Acked-by: Wei Liu <wei.liu at kernel.org> Reviewed-by: Juergen Gross <jgross at suse.com> # Xen related part Cc: Andrew Morton <akpm at

>> Now, let's clarify what I want regarding virtio-mem: >> >> 1. kexec should not add virtio-mem memory to the initial firmware >> memmap. The driver has to be in charge as discussed. >> 2. kexec should not place kexec images onto virtio-mem memory. That >> would end badly. >> 3. kexec should still dump virtio-mem memory via kdump. > > Ok,

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

This series is based on [1]: [PATCH v2 00/10] virtio-mem: paravirtualized memory That will hopefull get picked up soon, rebased to -next. The following patches were reverted from -next [2]: [PATCH 0/3] kexec/memory_hotplug: Prevent removal and accidental use As discussed in that thread, they should be reverted from -next already. In theory, if people agree, we could take the first two patches

This is the follow-up of "[PATCH RFCv1 0/5] mm/memory_hotplug: selective merging of memory resources" [1] Some add_memory*() users add memory in small, contiguous memory blocks. Examples include virtio-mem, hyper-v balloon, and the XEN balloon. This can quickly result in a lot of memory resources, whereby the actual resource boundaries are not of interest (e.g., it might be relevant

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

@Andrew, @Mst, I suggest the whole series (including the virtio-mem change) goes via the -mm tree. Currently, virtio-mem does not really support ZONE_MOVABLE. While it allows to online fully plugged memory blocks to ZONE_MOVABLE, it does not allow to online partially-plugged memory blocks to ZONE_MOVABLE and will never consider such memory blocks when unplugging memory. This might be surprising

For 5.10. Patch #1-#4,#6 have RBs or ACKs, patch #5 is virtio-mem stuff maintained by me. This should go via the -mm tree. --- When introducing virtio-mem, the semantics of ZONE_MOVABLE were rather unclear, which is why we special-cased ZONE_MOVABLE such that partially plugged blocks would never end up in ZONE_MOVABLE. Now that the semantics are much clearer (and are documented in patch #6),

For 5.10. Patch #1-#4,#6 have RBs or ACKs, patch #5 is virtio-mem stuff maintained by me. This should go via the -mm tree. --- When introducing virtio-mem, the semantics of ZONE_MOVABLE were rather unclear, which is why we special-cased ZONE_MOVABLE such that partially plugged blocks would never end up in ZONE_MOVABLE. Now that the semantics are much clearer (and are documented in patch #6),

@Andrew can we give this a churn and consider it for v5.9 in case there are no more comments? Patch #1-#4,#6 have RBss or ACKs, patch #5 is virtio-mem stuff maintained by me (and MST is aware). --- When introducing virtio-mem, the semantics of ZONE_MOVABLE were rather unclear, which is why we special-cased ZONE_MOVABLE such that partially plugged blocks would never end up in ZONE_MOVABLE. Now