similar to: [PATCH v2 0/3] mm/memory_hotplug: Allow to not create firmware memmap entries

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

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

On 29.04.20 18:08, David Hildenbrand wrote: > Some paravirtualized devices that add memory via add_memory() and > friends (esp. virtio-mem) don't want to create entries in > /sys/firmware/memmap/ - primarily to hinder kexec from adding this > memory to the boot memmap of the kexec kernel. > > In fact, such memory is never exposed via the firmware (e.g., e820), but > only

On 29.04.20 18:08, David Hildenbrand wrote: > Some paravirtualized devices that add memory via add_memory() and > friends (esp. virtio-mem) don't want to create entries in > /sys/firmware/memmap/ - primarily to hinder kexec from adding this > memory to the boot memmap of the kexec kernel. > > In fact, such memory is never exposed via the firmware (e.g., e820), but > only

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

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

On 4/30/20 3:29 AM, David Hildenbrand wrote: > Currently, when adding memory, we create entries in /sys/firmware/memmap/ > as "System RAM". This does not reflect the reality and will lead to > kexec-tools to add that memory to the fixed-up initial memmap for a > kexec kernel (loaded via kexec_load()). The memory will be considered > initial System RAM by the kexec kernel.

On 30.04.20 10:11, Dan Williams wrote: > On Thu, Apr 30, 2020 at 12:20 AM David Hildenbrand <david at redhat.com> wrote: >> >> On 29.04.20 18:08, David Hildenbrand wrote: >>> Some paravirtualized devices that add memory via add_memory() and >>> friends (esp. virtio-mem) don't want to create entries in >>> /sys/firmware/memmap/ - primarily to

Hi, Here is the third version of memory hotplug support for Xen guests patch. This one cleanly applies to git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git repository, xen/memory-hotplug head. On Fri, Aug 06, 2010 at 04:03:18PM +0400, Vasiliy G Tolstov wrote: [...] > Testing on sles 11 sp1 and opensuse 11.3. On results - send e-mail.. Thx. On Fri, Aug 06, 2010 at 12:34:08PM

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 added memory resources can contain inaccessible parts ("unblocked memory blocks"), blindly forwarding them to a kexec kernel is

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 added memory resources can contain inaccessible parts ("unblocked memory blocks"), blindly forwarding them to a kexec kernel is

David Hildenbrand <david at redhat.com> writes: > Some devices/drivers that add memory via add_memory() and friends (e.g., > dax/kmem, but also virtio-mem in the future) don't want to create entries > in /sys/firmware/memmap/ - primarily to hinder kexec from adding this > memory to the boot memmap of the kexec kernel. > > In fact, such memory is never exposed via the

David Hildenbrand <david at redhat.com> writes: > Some devices/drivers that add memory via add_memory() and friends (e.g., > dax/kmem, but also virtio-mem in the future) don't want to create entries > in /sys/firmware/memmap/ - primarily to hinder kexec from adding this > memory to the boot memmap of the kexec kernel. > > In fact, such memory is never exposed via the

Hi David, I love your patch! Yet something to improve: [auto build test ERROR on next-20200909] [cannot apply to mmotm/master hnaz-linux-mm/master xen-tip/linux-next powerpc/next linus/master v5.9-rc4 v5.9-rc3 v5.9-rc2 v5.9-rc4] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in

Currently, when adding memory, we create entries in /sys/firmware/memmap/ as "System RAM". This does not reflect the reality and will lead to kexec-tools to add that memory to the fixed-up initial memmap for a kexec kernel (loaded via kexec_load()). The memory will be considered initial System RAM by the kexec kernel. We should let the kexec kernel decide how to use that memory - just

>> 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,