|
 |
ae23c9 |
From db20a3f422ca948784aa74375d1977b7d0a1c7ed Mon Sep 17 00:00:00 2001
|
|
|
ae23c9 |
From: Cornelia Huck <cohuck@redhat.com>
|
|
|
ae23c9 |
Date: Tue, 15 May 2018 07:33:45 +0000
|
|
|
ae23c9 |
Subject: s390x/css: disabled subchannels cannot be status pending
|
|
|
ae23c9 |
|
|
|
ae23c9 |
The 3270 code will try to post an attention interrupt when the
|
|
|
ae23c9 |
3270 emulator (e.g. x3270) attaches. If the guest has not yet
|
|
|
ae23c9 |
enabled the subchannel for the 3270 device, we will present a spurious
|
|
|
ae23c9 |
cc 1 (status pending) when it uses msch on it later on, e.g. when
|
|
|
ae23c9 |
trying to enable the subchannel.
|
|
|
ae23c9 |
|
|
|
ae23c9 |
To fix this, just don't do anything in css_conditional_io_interrupt()
|
|
|
ae23c9 |
if the subchannel is not enabled. The 3270 code will work fine with
|
|
|
ae23c9 |
that, and the other user of this function (virtio-ccw) never
|
|
|
ae23c9 |
attempts to post an interrupt for a disabled device to begin with.
|
|
|
ae23c9 |
|
|
|
ae23c9 |
CC: qemu-stable@nongnu.org
|
|
|
ae23c9 |
Reported-by: Thomas Huth <thuth@redhat.com>
|
|
|
ae23c9 |
Tested-by: Thomas Huth <thuth@redhat.com>
|
|
|
ae23c9 |
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
|
|
|
ae23c9 |
Acked-by: Halil Pasic <pasic@linux.ibm.com>
|
|
|
ae23c9 |
Reviewed-by: David Hildenbrand <david@redhat.com>
|
|
|
ae23c9 |
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
|
|
|
ae23c9 |
(cherry picked from commit 6e9c893ecd00afd5344c35d0d0ded50eaa0938f6)
|
|
|
ae23c9 |
---
|
|
|
ae23c9 |
hw/s390x/css.c | 8 ++++++++
|
|
|
ae23c9 |
1 file changed, 8 insertions(+)
|
|
|
ae23c9 |
|
|
|
ae23c9 |
diff --git a/hw/s390x/css.c b/hw/s390x/css.c
|
|
|
ae23c9 |
index 301bf17..56c3fa8 100644
|
|
|
ae23c9 |
--- a/hw/s390x/css.c
|
|
|
ae23c9 |
+++ b/hw/s390x/css.c
|
|
|
ae23c9 |
@@ -617,6 +617,14 @@ void css_inject_io_interrupt(SubchDev *sch)
|
|
|
ae23c9 |
void css_conditional_io_interrupt(SubchDev *sch)
|
|
|
ae23c9 |
{
|
|
|
ae23c9 |
/*
|
|
|
ae23c9 |
+ * If the subchannel is not enabled, it is not made status pending
|
|
|
ae23c9 |
+ * (see PoP p. 16-17, "Status Control").
|
|
|
ae23c9 |
+ */
|
|
|
ae23c9 |
+ if (!(sch->curr_status.pmcw.flags & PMCW_FLAGS_MASK_ENA)) {
|
|
|
ae23c9 |
+ return;
|
|
|
ae23c9 |
+ }
|
|
|
ae23c9 |
+
|
|
|
ae23c9 |
+ /*
|
|
|
ae23c9 |
* If the subchannel is not currently status pending, make it pending
|
|
|
ae23c9 |
* with alert status.
|
|
|
ae23c9 |
*/
|
|
|
ae23c9 |
--
|
|
|
ae23c9 |
1.8.3.1
|
|
|
ae23c9 |
|