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From: Kai Backman <kaib@google.com>
To: qemu-devel@nongnu.org
Subject: [Qemu-devel] problems with mmap on qemu-arm
Date: Wed, 17 Jun 2009 20:54:33 +0300	[thread overview]
Message-ID: <c7187c3d0906171054m7037bf78va250ec93a6b580e8@mail.gmail.com> (raw)

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I'm running qemu-arm and see the following output from mmap with 'strace
qemu-arm -strace' (for both host and traget strace output):
mmap(NULL, 32800, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) =
0x2ad329b46000
4023 mmap(0,131072,7,34,-1,0) = 0xfffffff2

When my program later tries to read memory at 0xfffffffe it fails with a
SIGSEGV:
Program received signal SIGSEGV, Segmentation fault.
1: x/i $pc  0xce30:     ldr     r1, [r5]
(gdb) i r
r5             0xfffffffe       -2

Why does qemu-arm return such high addresses on a 32 bit platform and why is
the memory inaccessible? If this doesn't seem like an obvious bug in my
code, where in the qemu code should I start looking for how mmap works?

 Kai

--
Kai Backman, Software Engineer, kaib@google.com

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             reply	other threads:[~2009-06-17 17:54 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-06-17 17:54 Kai Backman [this message]
2009-06-17 20:38 ` [Qemu-devel] Re: problems with mmap on qemu-arm Kai Backman
2009-06-18 18:55   ` Riku Voipio

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