From 9b54ca0ba781012eeea4237b7c4832ba2ea81d89 Mon Sep 17 00:00:00 2001 From: David Gibson Date: Tue, 15 Nov 2016 10:08:42 +1100 Subject: [PATCH] spapr: Fix migration of PCI host bridges from qemu-2.7 daa2369 "spapr_pci: Add a 64-bit MMIO window" subtly broke migration from qemu-2.7 to the current version. It split the device's MMIO window into two pieces for 32-bit and 64-bit MMIO. The patch included backwards compatibility code to convert the old property into the new format. However, the property value was also transferred in the migration stream and compared with a (probably unwise) VMSTATE_EQUAL. So, the "raw" value from 2.7 is compared to the new style converted value from (pre-)2.8 giving a mismatch and migration failure. Although it would be technically possible to fix this in a way allowing backwards migration, that would leave an ugly legacy around indefinitely. This patch takes the simpler approach of bumping the migration version, dropping the unwise VMSTATE_EQUAL (and some equally unwise ones around it) and ignoring them on an incoming migration. Signed-off-by: David Gibson Reviewed-by: Alexey Kardashevskiy --- hw/ppc/spapr_pci.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) diff --git a/hw/ppc/spapr_pci.c b/hw/ppc/spapr_pci.c index 7cde30ee09..f9661b7d1a 100644 --- a/hw/ppc/spapr_pci.c +++ b/hw/ppc/spapr_pci.c @@ -1658,19 +1658,25 @@ static int spapr_pci_post_load(void *opaque, int version_id) return 0; } +static bool version_before_3(void *opaque, int version_id) +{ + return version_id < 3; +} + static const VMStateDescription vmstate_spapr_pci = { .name = "spapr_pci", - .version_id = 2, + .version_id = 3, .minimum_version_id = 2, .pre_save = spapr_pci_pre_save, .post_load = spapr_pci_post_load, .fields = (VMStateField[]) { VMSTATE_UINT64_EQUAL(buid, sPAPRPHBState), - VMSTATE_UINT32_EQUAL(dma_liobn[0], sPAPRPHBState), - VMSTATE_UINT64_EQUAL(mem_win_addr, sPAPRPHBState), - VMSTATE_UINT64_EQUAL(mem_win_size, sPAPRPHBState), - VMSTATE_UINT64_EQUAL(io_win_addr, sPAPRPHBState), - VMSTATE_UINT64_EQUAL(io_win_size, sPAPRPHBState), + VMSTATE_UNUSED_TEST(version_before_3, + sizeof(uint32_t) /* dma_liobn[0] */ + + sizeof(uint64_t) /* mem_win_addr */ + + sizeof(uint64_t) /* mem_win_size */ + + sizeof(uint64_t) /* io_win_addr */ + + sizeof(uint64_t) /* io_win_size */), VMSTATE_STRUCT_ARRAY(lsi_table, sPAPRPHBState, PCI_NUM_PINS, 0, vmstate_spapr_pci_lsi, struct spapr_pci_lsi), VMSTATE_INT32(msi_devs_num, sPAPRPHBState), -- 2.11.0