Re: UML fails to locate address space

From: linux-os (Dick Johnson)
Date: Tue May 20 2008 - 17:54:58 EST

On Tue, 20 May 2008, Jeff Dike wrote:

> On Tue, May 20, 2008 at 11:22:08AM -0400, linux-os (Dick Johnson) wrote:
>> Does this mean that I cannot mmap() address zero in the kernel
>> anymore? I should be able (in the kernel) read anything, and
>> then mmap() it to something usable in user-space. If address
>> zero is now artifically trapped there are problems being created
>> for no good reason at all.
> We're operating from userspace here.
> In any case, this hasn't happened with any kernel I've seen, but I'm
> suspicious that Ubuntu has started treating page zero specially.
> Jeff

Okay, then instead of putting a NULL in the "hint" to mmap() try
something else (0x1000?). That may help.

Dick Johnson
Penguin : Linux version on an i686 machine (5588.29 BogoMips).
My book :

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