@@ -2376,15 +2376,25 @@ static void spapr_phb_placement(sPAPRMachineState *spapr, uint32_t index,
unsigned n_dma, uint32_t *liobns, Error **errp)
{
const uint64_t base_buid = 0x800000020000000ULL;
- const hwaddr phb0_base = 0x10000000000ULL; /* 1 TiB */
const hwaddr phb_spacing = 0x1000000000ULL; /* 64 GiB */
const hwaddr mmio_offset = 0xa0000000; /* 2 GiB + 512 MiB */
const hwaddr pio_offset = 0x80000000; /* 2 GiB */
const uint32_t max_index = 255;
+ const hwaddr phb0_alignment = 0x10000000000ULL; /* 1 TiB */
- hwaddr phb_base;
+ uint64_t ram_top = MACHINE(spapr)->ram_size;
+ hwaddr phb0_base, phb_base;
int i;
+ if (MACHINE(spapr)->maxram_size > ram_top) {
+ ram_top = spapr->hotplug_memory.base +
+ memory_region_size(&spapr->hotplug_memory.mr);
+ }
+
+ phb0_base = QEMU_ALIGN_UP(ram_top, phb0_alignment);
+
+ fprintf(stderr, "DEBUG: ram_top = 0x%016"PRIx64" phb0 @ 0x%016"HWADDR_PRIX"\n",
+ ram_top, phb0_base);
if (index > max_index) {
error_setg(errp, "\"index\" for PAPR PHB is too large (max %u)",
max_index);
Currently the default PCI host bridge for the 'pseries' machine type is constructed with its IO windows in the 1TiB..(1TiB + 64GiB) range in guest memory space. This means that if > 1TiB of guest RAM is specified, the RAM will collide with the PCI IO windows, causing serious problems. Problems won't be obvious until guest RAM goes a bit beyond 1TiB, because there's a little unused space at the bottom of the area reserved for PCI, but essentially this means that > 1TiB of RAM has never worked with the pseries machine type. This patch fixes this by altering the placement of PHBs on large-RAM VMs. Instead of always placing the first PHB at 1TiB, it is placed at the next 1 TiB boundary after the maximum RAM address. Technically, this changes behaviour in a migration-breaking way for existing machines with > 1TiB maximum memory, but since having > 1 TiB memory was broken anyway, this seems like a reasonable trade-off. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> --- hw/ppc/spapr.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-)