From: Juergen Gross <jgross@suse.com>
Date: Thu, 25 Oct 2018 07:54:15 +0000 (+0200)
Subject: xen/pvh: don't try to unplug emulated devices
X-Git-Tag: v4.18.19~150
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9c47f44d0a93368e22893f6368fc57a44143d468;p=thirdparty%2Fkernel%2Fstable.git

xen/pvh: don't try to unplug emulated devices

commit e6111161c0a02d58919d776eec94b313bb57911f upstream.

A Xen PVH guest has no associated qemu device model, so trying to
unplug any emulated devices is making no sense at all.

Bail out early from xen_unplug_emulated_devices() when running as PVH
guest. This will avoid issuing the boot message:

[    0.000000] Xen Platform PCI: unrecognised magic value

Cc: <stable@vger.kernel.org> # 4.11
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/arch/x86/xen/platform-pci-unplug.c b/arch/x86/xen/platform-pci-unplug.c
index 33a783c77d969..184b369223979 100644
--- a/arch/x86/xen/platform-pci-unplug.c
+++ b/arch/x86/xen/platform-pci-unplug.c
@@ -146,6 +146,10 @@ void xen_unplug_emulated_devices(void)
 {
 	int r;
 
+	/* PVH guests don't have emulated devices. */
+	if (xen_pvh_domain())
+		return;
+
 	/* user explicitly requested no unplug */
 	if (xen_emul_unplug & XEN_UNPLUG_NEVER)
 		return;