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Date: Fri, 26 Sep 2008 14:24:43 -0400 (EDT)
From: Vince Weaver <vince@csl.cornell.edu>
Message-ID: <20080926142222.U24737@stanley.csl.cornell.edu>
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Subject: [Qemu-devel] linux-user mremap()
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Until the linux-user mremap() problem is fixed (the one where a 64-bit 
value can be returned even on a 32-bit target), might it make sense to 
apply a patch like this?

This will at least let users know what the problem is, instead of just 
segfaulting.

Vince




Index: mmap.c
===================================================================
--- mmap.c	(revision 5321)
+++ mmap.c	(working copy)
@@ -538,6 +538,13 @@
      mmap_lock();
      /* XXX: use 5 args syscall */
      host_addr = (long)mremap(g2h(old_addr), old_size, new_size, flags);
+#if TARGET_ABI_BITS == 32
+    if (host_addr > 0xffffffff) {
+       printf("ERROR!  mremap() returned 64-bit value on 32-bit target!\n\n");
+       exit(-1); 
+    }
+#endif 
+
      if (host_addr == -1) {
          new_addr = -1;
      } else {