Igor Mammedov 98e753a6e5 pc/fwcfg: unbreak migration from qemu-2.5 and qemu-2.6 during firmware boot ... Since 2.7 commit (b2a575a Add optionrom compatible with fw_cfg DMA version) regressed migration during firmware exection time by abusing fwcfg.dma_enabled property to decide loading dma version of option rom AND by mistake disabling DMA for 2.6 and earlier globally instead of only for option rom. so 2.6 machine type guest is broken when it already runs firmware in DMA mode but migrated to qemu-2.7(pc-2.6) at that time; a) qemu-2.6:pc2.6 (fwcfg.dma=on,firmware=dma,oprom=ioport) b) qemu-2.7:pc2.6 (fwcfg.dma=off,firmware=ioport,oprom=ioport) to: a b from a OK FAIL b OK OK So we currently have broken forward migration from qemu-2.6 to qemu-2.[789] that however could be fixed for 2.10 by re-enabling DMA for 2.[56] machine types and allowing dma capable option rom only since 2.7. As result qemu should end up with: c) qemu-2.10:pc2.6 (fwcfg.dma=on,firmware=dma,oprom=ioport) to: a b c from a OK FAIL OK b OK OK OK c OK FAIL OK where forward migration from qemu-2.6 to qemu-2.10 should work again leaving only qemu-2.[789]:pc-2.6 broken. Reported-by: Eduardo Habkost <ehabkost@redhat.com> Analyzed-by: Laszlo Ersek <lersek@redhat.com> Signed-off-by: Igor Mammedov <imammedo@redhat.com> Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eduardo Habkost <ehabkost@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>		2017-05-10 22:04:23 +03:00
..
apic-msidef.h	q35: ioapic: add support for emulated IOAPIC IR	2016-07-21 20:43:49 +03:00
apic.h	apic: move target-dependent definitions to cpu.h	2016-05-19 16:42:28 +02:00
apic_internal.h	Revert "apic: save apic_delivered flag"	2017-03-27 14:41:01 +02:00
ich9.h	tco: do not generate an NMI	2017-04-05 17:23:52 +02:00
intel_iommu.h	intel_iommu: enable remote IOTLB	2017-04-20 15:22:41 -03:00
ioapic.h	Clean up decorations and whitespace around header guards	2016-07-12 16:20:46 +02:00
ioapic_internal.h	x86: ioapic: add support for explicit EOI	2016-08-03 18:44:57 +02:00
pc.h	pc/fwcfg: unbreak migration from qemu-2.5 and qemu-2.6 during firmware boot	2017-05-10 22:04:23 +03:00
topology.h	pc: Add x86_topo_ids_from_apicid()	2016-07-20 11:58:44 -03:00
x86-iommu.h	intel_iommu: support device iotlb descriptor	2017-01-10 05:56:58 +02:00