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Re: [Xen-devel] bitopts functions overflowing page boundarys

On 28 May 2005, at 05:43, Scott Parish wrote:

u.inuse.type_info is at the end of the pfn_info structure, and is
u32 for both x86_32 and x86_64--in this location it can also be the
last 32 bits of a page.

several functions use bitopts.h functions to manipulate this member, and
on x86_64 these functions use u64 instructions, which will overflow the
page boundary, and possibly the end of memory as we see here:

You really see this in practise? I'm very surprised. The memory map would have to be just big enough that the last pfn_info structure falls at the end of an aligned 2MB boundary. If you reduce max_page by 1, does the problem disappear?

 -- Keir

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