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Re: [Xen-devel] bitopts functions overflowing page boundarys
| To: | "Scott Parish" <srparish@xxxxxxxxxx> |
|---|---|
| Subject: | Re: [Xen-devel] bitopts functions overflowing page boundarys |
| From: | Keir Fraser <Keir.Fraser@xxxxxxxxxxxx> |
| Date: | Sat, 28 May 2005 10:01:27 +0100 |
| Cc: | xen-devel@xxxxxxxxxxxxxxxxxxx |
| Delivery-date: | Sat, 28 May 2005 09:04:05 +0000 |
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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, andon 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 _______________________________________________ Xen-devel mailing list Xen-devel@xxxxxxxxxxxxxxxxxxx http://lists.xensource.com/xen-devel |
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