From: Ulrich Drepper <drepper@redhat.com>
To: root@chaos.analogic.com
Cc: Linux kernel <linux-kernel@vger.kernel.org>
Subject: Re: syscall __NR_mmap2
Date: Mon, 07 Jul 2003 14:32:31 -0700 [thread overview]
Message-ID: <3F09E6EF.8000806@redhat.com> (raw)
In-Reply-To: <Pine.LNX.4.53.0307071655470.22074@chaos>
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Richard B. Johnson wrote:
> write(1, "Addr = 000b8000\n", 16) = 16
> open("/dev/mem", O_RDWR) = 3
> mmap2(0xb8000, 8192, PROT_READ|PROT_WRITE, MAP_SHARED|MAP_FIXED, 3, 0xb8000) = 0xb8000
mmap64() (and if you compile glibc with an adequate minimal kernel
requirement mmap as well) is implemented using mmap2. It works nicely.
Admittedly, I haven't used the stock 2.4 kernel. And I also haven't
used /dev/mem. But at least for the first part I would expect to see
problem reports since the code is used and glibc wouldn't work.
In your code, assuming this is x86, do you really want to read the
memory starting at address 0xb8000000? This is what your code does. I
don't know enough about the kernel memory layout to say whether
something is supposed to be there or not.
- --
- --------------. ,-. 444 Castro Street
Ulrich Drepper \ ,-----------------' \ Mountain View, CA 94041 USA
Red Hat `--' drepper at redhat.com `---------------------------
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next prev parent reply other threads:[~2003-07-07 21:18 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2003-07-07 21:00 syscall __NR_mmap2 Richard B. Johnson
2003-07-07 21:32 ` Ulrich Drepper [this message]
2003-07-08 11:56 ` Richard B. Johnson
2003-07-08 0:36 ` Jamie Lokier
2003-07-08 11:54 ` Richard B. Johnson
2003-07-08 13:59 ` Kurt Wall
2003-07-08 14:05 ` Jamie Lokier
2003-07-08 14:40 ` Richard B. Johnson
2003-07-08 14:49 ` Randy.Dunlap
2003-07-08 14:51 ` Kurt Wall
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