Re: [Qemu-devel] [PATCH] spapr_pci: Advertise MSI quota

[Alexey Kardashevskiy <aik@ozlabs.ru>]

On 06/11/2014 06:06 PM, Alexander Graf wrote:
> 
> On 11.06.14 10:05, Alexey Kardashevskiy wrote:
>> From: Badari Pulavarty <pbadari@us.ibm.com>
>>
>> Hotplug of multiple disks fails due to MSI vector quota check.
>> Number of MSI vectors default to 8 allowing only 4 devices.
>> This happens on RHEL6.5 guest. RHEL7 and SLES11 guests fallback
>> to INTX.
>>
>> One way to workaround the issue is to increase total MSIs,
>> so that MSI quota check allows us to hotplug multiple disks.
>>
>> Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
>> Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
>> ---
>>   hw/ppc/spapr_pci.c | 2 ++
>>   1 file changed, 2 insertions(+)
>>
>> diff --git a/hw/ppc/spapr_pci.c b/hw/ppc/spapr_pci.c
>> index ddfd8bb..ebd92fd 100644
>> --- a/hw/ppc/spapr_pci.c
>> +++ b/hw/ppc/spapr_pci.c
>> @@ -831,6 +831,7 @@ int spapr_populate_pci_dt(sPAPRPHBState *phb,
>>       int bus_off, i, j;
>>       char nodename[256];
>>       uint32_t bus_range[] = { cpu_to_be32(0), cpu_to_be32(0xff) };
>> +    uint16_t nmsi = 64;
> 
> Why 64?

Why not? :)
We need some number here instead of default 8, that's pretty much it. 256?


> 
> 
> Alex
> 
>>       struct {
>>           uint32_t hi;
>>           uint64_t child;
>> @@ -879,6 +880,7 @@ int spapr_populate_pci_dt(sPAPRPHBState *phb,
>>       _FDT(fdt_setprop(fdt, bus_off, "ranges", &ranges, sizeof(ranges)));
>>       _FDT(fdt_setprop(fdt, bus_off, "reg", &bus_reg, sizeof(bus_reg)));
>>       _FDT(fdt_setprop_cell(fdt, bus_off, "ibm,pci-config-space-type",
>> 0x1));
>> +    _FDT(fdt_setprop(fdt, bus_off, "ibm,pe-total-#msi", &nmsi,
>> sizeof(nmsi)));
>>         /* Build the interrupt-map, this must matches what is done
>>        * in pci_spapr_map_irq
> 


-- 
Alexey