From dc9e46a29aad8ba5d2fb0871268baa9c7edc0f95 Mon Sep 17 00:00:00 2001
From: Ross Lagerwall <ross.lagerwall@citrix.com>
Date: Mon, 14 May 2018 10:57:46 +0100
Subject: [PATCH] xen_pt: Present the size of 64 bit BARs correctly

The full size of the BAR is stored in the lower PCIIORegion.size. The
upper PCIIORegion.size is 0.  Calculate the size of the upper half
correctly from the lower half otherwise the size read by the guest will
be incorrect.

Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
---
 hw/xen/xen_pt_config_init.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/hw/xen/xen_pt_config_init.c b/hw/xen/xen_pt_config_init.c
index a3ce33e78b..aee31c62bb 100644
--- a/hw/xen/xen_pt_config_init.c
+++ b/hw/xen/xen_pt_config_init.c
@@ -504,6 +504,8 @@ static int xen_pt_bar_reg_write(XenPCIPassthroughState *s, XenPTReg *cfg_entry,
         bar_ro_mask = XEN_PT_BAR_IO_RO_MASK | (r_size - 1);
         break;
     case XEN_PT_BAR_FLAG_UPPER:
+        assert(index > 0);
+        r_size = d->io_regions[index - 1].size >> 32;
         bar_emu_mask = XEN_PT_BAR_ALLF;
         bar_ro_mask = r_size ? r_size - 1 : 0;
         break;