On Mon, 8 Apr 2013 11:09:53 -0600 Toshi Kani <toshi.kani@xxxxxx> wrote: > Memory hot-delete to a memory range present at boot causes an > error message in __release_region(), such as: > > Trying to free nonexistent resource <0000000070000000-0000000077ffffff> > > Hot-delete operation still continues since __release_region() is > a void function, but the target memory range is not freed from > iomem_resource as the result. This also leads a failure in a > subsequent hot-add operation to the same memory range since the > address range is still in-use in iomem_resource. > > This problem happens because the granularity of memory resource ranges > may be different between boot and hot-delete. So we don't need this new code if CONFIG_MEMORY_HOTPLUG=n? If so, can we please arrange for it to not be present if the user doesn't need it? > During bootup, > iomem_resource is set up from the boot descriptor table, such as EFI > Memory Table and e820. Each resource entry usually covers the whole > contiguous memory range. Hot-delete request, on the other hand, may > target to a particular range of memory resource, and its size can be > much smaller than the whole contiguous memory. Since the existing > release interfaces like __release_region() require a requested region > to be exactly matched to a resource entry, they do not allow a partial > resource to be released. > > This patchset introduces release_mem_region_adjustable() for memory > hot-delete operations, which allows releasing a partial memory range > and adjusts remaining resource accordingly. This patchset makes no > changes to the existing interfaces since their restriction is still > valid for I/O resources. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>