qemu-xen-trad/pt_msi_disable: do not clear all MSI flags

"qemu-xen-trad: fix msi_translate with PV event delivery" added a
pt_msi_disable() call into pt_msgctrl_reg_write, clearing the MSI flags
as a consequence. MSIs get enabled again soon after by calling
pt_msi_setup.

However the MSI flags are only setup once in the pt_msgctrl_reg_init
function, so from the QEMU point of view the device has lost some
important properties, like for example PCI_MSI_FLAGS_64BIT.

This patch fixes the bug by clearing only the MSI
enabled/mapped/initialized flags in pt_msi_disable.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Tested-by: G.R. <firemeteor@users.sourceforge.net>
Xen-devel: http://marc.info/?l=xen-devel&m=135489879503075

diff --git a/hw/pt-msi.c b/hw/pt-msi.c
index 73f737d00080740af9a17480636496ffe201598a..b03b9890eaa335487a1584f39f6e0cdf7e25cb78 100644 (file)
--- a/hw/pt-msi.c
+++ b/hw/pt-msi.c
@@ -213,7 +213,7 @@ void pt_msi_disable(struct pt_dev *dev)
 
 out:
     /* clear msi info */
-    dev->msi->flags = 0;
+    dev->msi->flags &= ~(MSI_FLAG_UNINIT | PT_MSI_MAPPED | PCI_MSI_FLAGS_ENABLE);
     dev->msi->pirq = -1;
     dev->msi_trans_en = 0;
 }