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Date: Mon, 24 May 2004 13:58:50 -0500
From: Tommy Reynolds <Tommy.Reynolds@MegaCoder.com>
To: "shanthi kiran pendyala" <skiranp@cisco.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: Mmap problem (VM_DENYWRITE)
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Uttered "shanthi kiran pendyala" <skiranp@cisco.com>, spake thus:

> After mmaping in userspace any writes to the mmap region is not working. 
> I think it is b'cos of the protection field in the vma is set to
> VM_DENYWRITE. 
> The complete prot flag is (VM_READ | VM_WRITE | VM_EXEC | VM_GROWSUP |
> VM_DENYWRITE)
> 
> Why is this happening? I need to have both read and write access to region.
> How do I fix this ?

Take out the VM_DENYWRITE flag. Duh.

Are you gonna put code in the mapped area?  No? Turn off VM_EXEC.

Are you gonna place your stack in the mapped area?  No? Turn of
VM_GROWSUP.

Have you read "man mmap"?  No? Try it.

Cheers!

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