Re: [Qemu-devel] [PATCH 1/1] msix: correct pba size calculation used for msix_exclusive_bar initialization

["Michael S. Tsirkin" <mst@redhat.com>]

On Mon, Dec 17, 2018 at 07:34:39AM +0800, Dongli Zhang wrote:
> The bar_pba_size is more than what the pba is expected to have, although
> this usually would not affect the bar_size used for dev->msix_exclusive_bar
> initialization.
> 
> Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com>


If this does ever have an effect, we need a compat config
for old machine types.
Could you explain a bit more? Are there configs affected?
What are these?


> ---
>  hw/pci/msix.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/hw/pci/msix.c b/hw/pci/msix.c
> index 702dac4..234c0a3 100644
> --- a/hw/pci/msix.c
> +++ b/hw/pci/msix.c
> @@ -345,7 +345,7 @@ int msix_init_exclusive_bar(PCIDevice *dev, unsigned short nentries,
>      char *name;
>      uint32_t bar_size = 4096;
>      uint32_t bar_pba_offset = bar_size / 2;
> -    uint32_t bar_pba_size = (nentries / 8 + 1) * 8;
> +    uint32_t bar_pba_size = QEMU_ALIGN_UP(nentries, 64) / 8;
>  
>      /*
>       * Migration compatibility dictates that this remains a 4k
> -- 
> 2.7.4