From: Aurelien Jarno <aurelien@aurel32.net>

s390_virtio_hypercall can trigger IO events and interrupts, most notably
when using virtio-ccw devices.

Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Fixes: 278f5e98c647 ("s390x/misc_helper.c: wrap IO instructions in BQL")
Signed-off-by: Alexander Graf <agraf@suse.de>
---
 target/s390x/misc_helper.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/target/s390x/misc_helper.c b/target/s390x/misc_helper.c
index 83d3894..eca8244 100644
--- a/target/s390x/misc_helper.c
+++ b/target/s390x/misc_helper.c
@@ -288,7 +288,9 @@ void HELPER(diag)(CPUS390XState *env, uint32_t r1, uint32_t r3, uint32_t num)
     switch (num) {
     case 0x500:
         /* KVM hypercall */
+        qemu_mutex_lock_iothread();
         r = s390_virtio_hypercall(env);
+        qemu_mutex_unlock_iothread();
         break;
     case 0x44:
         /* yield */
-- 
1.8.5.6