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Discarding it would only cause unnecessary reallocation of memory after each conversion. Instead, only enable it for non-in-place conversions. Signed-off-by: Michael Roth --- accel/kvm/kvm-all.c | 22 ++++++++++++---------- 1 file changed, 12 insertions(+), 10 deletions(-) diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c index ff07050935..b28c9fbd33 100644 --- a/accel/kvm/kvm-all.c +++ b/accel/kvm/kvm-all.c @@ -3611,17 +3611,19 @@ static int kvm_post_convert_section(MemoryRegionSection *section, bool to_privat } } - if (to_private) { - if (rb->page_size != qemu_real_host_page_size()) { - /* - * shared memory is backed by hugetlb, which is supposed to be - * pre-allocated and doesn't need to be discarded - */ - return 0; + if (!machine_require_guest_memfd_convert_in_place(current_machine)) { + if (to_private) { + if (rb->page_size != qemu_real_host_page_size()) { + /* + * shared memory is backed by hugetlb, which is supposed to be + * pre-allocated and doesn't need to be discarded + */ + return 0; + } + ret = ram_block_discard_shared_range(rb, offset, size); + } else { + ret = ram_block_discard_guest_memfd_range(rb, offset, size); } - ret = ram_block_discard_shared_range(rb, offset, size); - } else { - ret = ram_block_discard_guest_memfd_range(rb, offset, size); } return ret; -- 2.43.0