From: Jan Kiszka <jan.kiszka@siemens.com>
Date: Mon, 2 Sep 2013 16:43:31 +0000 (+0200)
Subject: Revert "memory: Return -1 again on reads from unsigned regions"
X-Git-Tag: qemu-xen-4.4.0-rc1~1^2~26
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=2a93d3dd32386c3522cfa2ee60c9e06a298d1f52;p=qemu-upstream-4.5-testing.git

Revert "memory: Return -1 again on reads from unsigned regions"

This reverts commit 9b8c69243585a32d14b9bb9fcd52c37b0b5a1b71.

The commit was wrong: We only return -1 on invalid accesses, not on
valid but unbacked ones. This broke various corner cases.

Cc: qemu-stable@nongnu.org
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
(cherry picked from commit 68a7439a150d6b4da99082ab454b9328b151bc25)

Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---

diff --git a/memory.c b/memory.c
index 886f83895..5a10fd0bd 100644
--- a/memory.c
+++ b/memory.c
@@ -872,7 +872,7 @@ static uint64_t unassigned_mem_read(void *opaque, hwaddr addr,
     if (current_cpu != NULL) {
         cpu_unassigned_access(current_cpu, addr, false, false, 0, size);
     }
-    return -1ULL;
+    return 0;
 }
 
 static void unassigned_mem_write(void *opaque, hwaddr addr,