Stumbling over "x-ignore-shared" migration support for virtio-mem on my todo list, I remember talking to Dave G. a while ago about how ram_block_discard_range() in MAP_PIRVATE file mappings is possibly harmful when the file is used somewhere else -- for example, with VM templating in multiple VMs.
This series adds a warning to ram_block_discard_range() in that problematic case and adds "x-ignore-shared" migration support for virtio-mem, which is pretty straight-forward. The last patch also documents how VM templating interacts with virtio-mem. Cc: "Michael S. Tsirkin" <[email protected]> Cc: Juan Quintela <[email protected]> Cc: Peter Xu <[email protected]> Cc: Leonardo Bras <[email protected]> Cc: Paolo Bonzini <[email protected]> Cc: "Philippe Mathieu-Daudé" <[email protected]> Cc: Peng Tao <[email protected]> David Hildenbrand (4): softmmu/physmem: Warn with ram_block_discard_range() on MAP_PRIVATE file mapping virtio-mem: Skip most of virtio_mem_unplug_all() without plugged memory migration/ram: Expose ramblock_is_ignored() as migrate_ram_is_ignored() virtio-mem: Support "x-ignore-shared" migration hw/virtio/virtio-mem.c | 67 ++++++++++++++++++++++++++++------------ include/migration/misc.h | 1 + migration/postcopy-ram.c | 2 +- migration/ram.c | 14 ++++----- migration/ram.h | 3 +- softmmu/physmem.c | 18 +++++++++++ 6 files changed, 76 insertions(+), 29 deletions(-) -- 2.40.1
