On Tue, Mar 02, 2021 at 10:43:55AM +0100, David Hildenbrand wrote: > On 02.03.21 10:06, Igor Mammedov wrote: > > On Mon, 1 Mar 2021 11:48:33 +0100 > > David Hildenbrand <da...@redhat.com> wrote: > > > > > The resizeable memory region that is created for the cmd blob has a > > > maximum > > > size of ACPI_BUILD_ALIGN_SIZE - 4k. This used to be sufficient, however, > > > as we try fitting in additional data (e.g., vmgenid, nvdimm, intel-iommu), > > > we require more than 4k and can crash QEMU when trying to resize the > > > resizeable memory region beyond its maximum size: > > > $ build/qemu-system-x86_64 --enable-kvm \ > > > -machine q35,nvdimm=on \ > > > -smp 1 \ > > > -cpu host \ > > > -m size=2G,slots=8,maxmem=4G \ > > > -object memory-backend-file,id=mem0,mem-path=/tmp/nvdimm,size=256M > > > \ > > > -device nvdimm,label-size=131072,memdev=mem0,id=nvdimm0,slot=1 \ > > > -nodefaults \ > > > -device vmgenid \ > > > -device intel-iommu > > > > I don't see what's here that would make cmd_blob go above 4k. > > can you try identify what actually fills it up (perhaps we have a hidden > > bug elsewhere)? > > VM initialization: > > bios_linker_loader_alloc: allocating memory for 'etc/acpi/tables' > -> new table size: 128 > bios_linker_loader_add_checksum: Adding checksum for 'etc/acpi/tables' for > range 64 - 9659 > -> new table size: 256 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to > 'etc/acpi/tables' > -> new table size: 384 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to > 'etc/acpi/tables' > -> new table size: 512 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to > 'etc/acpi/tables' > -> new table size: 640 > bios_linker_loader_add_checksum: Adding checksum for 'etc/acpi/tables' for > range 9659 - 9903 > -> new table size: 768 > bios_linker_loader_add_checksum: Adding checksum for 'etc/acpi/tables' for > range 9903 - 10023 > -> new table size: 896 > bios_linker_loader_alloc: allocating memory for 'etc/vmgenid_guid' > -> new table size: 1024 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to > 'etc/vmgenid_guid' > -> new table size: 1280 > bios_linker_loader_add_checksum: Adding checksum for 'etc/acpi/tables' for > range 10023 - 10225 > -> new table size: 1408 > bios_linker_loader_add_checksum: Adding checksum for 'etc/acpi/tables' for > range 10225 - 10281 > -> new table size: 1536 > bios_linker_loader_add_checksum: Adding checksum for 'etc/acpi/tables' for > range 10281 - 10505 > -> new table size: 1664 > bios_linker_loader_add_checksum: Adding checksum for 'etc/acpi/tables' for > range 10505 - 10577 > -> new table size: 1792 > bios_linker_loader_alloc: allocating memory for 'etc/acpi/nvdimm-mem' > -> new table size: 1920 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to > 'etc/acpi/nvdimm-mem' > -> new table size: 2048 > bios_linker_loader_add_checksum: Adding checksum for 'etc/acpi/tables' for > range 10577 - 11471 > -> new table size: 2176 > bios_linker_loader_add_checksum: Adding checksum for 'etc/acpi/tables' for > range 11471 - 11695 > -> new table size: 2304 > bios_linker_loader_add_checksum: Adding checksum for 'etc/acpi/tables' for > range 11695 - 11735 > -> new table size: 2432 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to > 'etc/acpi/tables' > -> new table size: 2560 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to > 'etc/acpi/tables' > -> new table size: 2688 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to > 'etc/acpi/tables' > -> new table size: 2816 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to > 'etc/acpi/tables' > -> new table size: 2944 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to > 'etc/acpi/tables' > -> new table size: 3072 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to > 'etc/acpi/tables' > -> new table size: 3200 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to > 'etc/acpi/tables' > -> new table size: 3328 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to > 'etc/acpi/tables' > -> new table size: 3456 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to > 'etc/acpi/tables' > -> new table size: 3584 > bios_linker_loader_add_checksum: Adding checksum for 'etc/acpi/tables' for > range 11735 - 11807 > -> new table size: 3712 > bios_linker_loader_alloc: allocating memory for 'etc/acpi/rsdp' > -> new table size: 3840 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/rsdp' to > 'etc/acpi/tables' > -> new table size: 3968 > bios_linker_loader_add_checksum: Adding checksum for 'etc/acpi/rsdp' for > range 0 - 20 > -> new table size: 4096 > > > When the bios/guest boots up: > > bios_linker_loader_alloc: allocating memory for 'etc/acpi/tables' > -> new table size: 128 > bios_linker_loader_add_checksum: Adding checksum for 'etc/acpi/tables' for > range 64 - 9769 > -> new table size: 256 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to > 'etc/acpi/tables' > -> new table size: 384 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to > 'etc/acpi/tables' > -> new table size: 512 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to > 'etc/acpi/tables' > -> new table size: 640 > bios_linker_loader_add_checksum: Adding checksum for 'etc/acpi/tables' for > range 9769 - 10013 > -> new table size: 768 > bios_linker_loader_add_checksum: Adding checksum for 'etc/acpi/tables' for > range 10013 - 10133 > -> new table size: 896 > bios_linker_loader_alloc: allocating memory for 'etc/vmgenid_guid' > -> new table size: 1024 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to > 'etc/vmgenid_guid' > -> new table size: 1280 > bios_linker_loader_add_checksum: Adding checksum for 'etc/acpi/tables' for > range 10133 - 10335 > -> new table size: 1408 > bios_linker_loader_add_checksum: Adding checksum for 'etc/acpi/tables' for > range 10335 - 10391 > -> new table size: 1536 > bios_linker_loader_add_checksum: Adding checksum for 'etc/acpi/tables' for > range 10391 - 10615 > -> new table size: 1664 > bios_linker_loader_add_checksum: Adding checksum for 'etc/acpi/tables' for > range 10615 - 10675 > -> new table size: 1792 > bios_linker_loader_add_checksum: Adding checksum for 'etc/acpi/tables' for > range 10675 - 10747 > -> new table size: 1920 > bios_linker_loader_alloc: allocating memory for 'etc/acpi/nvdimm-mem' > -> new table size: 2048 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to > 'etc/acpi/nvdimm-mem' > -> new table size: 2176 > bios_linker_loader_add_checksum: Adding checksum for 'etc/acpi/tables' for > range 10747 - 11641 > -> new table size: 2304 > bios_linker_loader_add_checksum: Adding checksum for 'etc/acpi/tables' for > range 11641 - 11865 > -> new table size: 2432 > bios_linker_loader_add_checksum: Adding checksum for 'etc/acpi/tables' for > range 11865 - 11905 > -> new table size: 2560 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to > 'etc/acpi/tables' > -> new table size: 2688 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to > 'etc/acpi/tables' > -> new table size: 2816 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to > 'etc/acpi/tables' > -> new table size: 2944 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to > 'etc/acpi/tables' > -> new table size: 3072 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to > 'etc/acpi/tables' > -> new table size: 3200 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to > 'etc/acpi/tables' > -> new table size: 3328 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to > 'etc/acpi/tables' > -> new table size: 3456 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to > 'etc/acpi/tables' > -> new table size: 3584 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to > 'etc/acpi/tables' > -> new table size: 3712 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to > 'etc/acpi/tables' > -> new table size: 3840 > bios_linker_loader_add_checksum: Adding checksum for 'etc/acpi/tables' for > range 11905 - 11981 > -> new table size: 3968 > bios_linker_loader_alloc: allocating memory for 'etc/acpi/rsdp' > -> new table size: 4096 > bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/rsdp' to > 'etc/acpi/tables' > -> new table size: 4224 > bios_linker_loader_add_checksum: Adding checksum for 'etc/acpi/rsdp' for > range 0 - 20 > -> new table size: 4352
yea it's because each command has space for 2 file names, so it's size is 128 bytes. So just 32 commands is 4k. Question is what is the extra table and why isn't it there before boot? -> bios_linker_loader_alloc: allocating memory for 'etc/acpi/rsdp' +> bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/tables' to 'etc/acpi/tables' > -> new table size: 3840 -> bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/rsdp' to 'etc/acpi/tables' +> bios_linker_loader_add_checksum: Adding checksum for 'etc/acpi/tables' for range 11905 - 11981 > -> new table size: 3968 -> bios_linker_loader_add_checksum: Adding checksum for 'etc/acpi/rsdp' for range 0 - 20 +> bios_linker_loader_alloc: allocating memory for 'etc/acpi/rsdp' > -> new table size: 4096 +> bios_linker_loader_add_pointer: adding pointer in 'etc/acpi/rsdp' to 'etc/acpi/tables' +> -> new table size: 4224 +> bios_linker_loader_add_checksum: Adding checksum for 'etc/acpi/rsdp' for range 0 - 20 +> -> new table size: 4352 simply put I would expect the command blob size to be the same before and after migration. > > > -- > Thanks, > > David / dhildenb
