[Qemu-devel] [PATCH] exec-migration: handle EINTR in popen_get_buffer()

[Uri Lublin <uril@redhat.com>]

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Hello,


The attached patch fix occasional failures of incoming exec migrations.

Patch based on qemu-kvm.git.

Uri.



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>From 0003cebfd2afdf03e2f2cff599691952950a05ce Mon Sep 17 00:00:00 2001
From: Uri Lublin <uril@redhat.com>
Date: Tue, 2 Jun 2009 17:09:57 +0300
Subject: [PATCH] exec-migration: handle EINTR in popen_get_buffer()

Upon interrupt, fread returns with no data, and
the (incoming exec) migration fails.

Fix by retrying on such a case.

Signed-off-by: Uri Lublin <uril@redhat.com>
---
 savevm.c |    7 ++++++-
 1 files changed, 6 insertions(+), 1 deletions(-)

diff --git a/savevm.c b/savevm.c
index 68ffd03..f53de43 100644
--- a/savevm.c
+++ b/savevm.c
@@ -215,7 +215,12 @@ static int popen_put_buffer(void *opaque, const uint8_t *buf, int64_t pos, int s
 static int popen_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size)
 {
     QEMUFilePopen *s = opaque;
-    return fread(buf, 1, size, s->popen_file);
+    int bytes;
+
+    do {
+        bytes = fread(buf, 1, size, s->popen_file);
+    } while ((bytes == 0) && (errno == EINTR));
+    return bytes;
 }

 static int popen_close(void *opaque)
-- 
1.6.2.2