From 652ce2d449f47cdc4d94eb67f2377504c06957ad Mon Sep 17 00:00:00 2001
From: Paolo Bonzini <pbonzini@redhat.com>
Date: Tue, 2 Feb 2010 20:33:10 +0100
Subject: [PATCH] loop write in qemu_event_increment upon EINTR

Same as what qemu-kvm does.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
---
 vl.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/vl.c b/vl.c
index f98661f34e..29f218987a 100644
--- a/vl.c
+++ b/vl.c
@@ -3217,8 +3217,12 @@ static void qemu_event_increment(void)
     if (io_thread_fd == -1)
         return;
 
-    ret = write(io_thread_fd, &byte, sizeof(byte));
-    if (ret < 0 && (errno != EINTR && errno != EAGAIN)) {
+    do {
+        ret = write(io_thread_fd, &byte, sizeof(byte));
+    } while (ret < 0 && errno == EINTR);
+
+    /* EAGAIN is fine, a read must be pending.  */
+    if (ret < 0 && errno != EAGAIN) {
         fprintf(stderr, "qemu_event_increment: write() filed: %s\n",
                 strerror(errno));
         exit (1);