From: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Date: Mon, 10 Dec 2012 12:43:33 +0000 (+0000)
Subject: qemu-xen-trad/pt_msi_disable: do not clear all MSI flags
X-Git-Tag: xen-4.3.0-rc1~3
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=adf74189dd58014744a4b8c9d64407d629da5e2f;p=qemu-xen-4.3-testing.git

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 73f737d00..b03b9890e 100644
--- 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;
 }