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Re: [Xen-devel] [patch] unwanted sign extending

To: Jan Beulich <JBeulich@xxxxxxxxxx>
Subject: Re: [Xen-devel] [patch] unwanted sign extending
From: "Scott Parish" <srparish@xxxxxxxxxx>
Date: Wed, 22 Jun 2005 11:20:29 +0000
Cc: xen-devel@xxxxxxxxxxxxxxxxxxx, Scott Parish <srparish@xxxxxxxxxx>
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On Wed, Jun 22, 2005 at 01:14:34AM -0600, Jan Beulich wrote:

> I'd think that for correctness this should also be done to
> alloc_l2_table. And I also think that this is still wrong for 64 bits:
> Shifting left an unsigned yields an unsigned, and since 'i' can range
> from 0 to 511 and the shift count is 30, the result is going to be
> truncated. That is, the code should be
>         vaddr = (unsigned long)i << L3_PAGETABLE_SHIFT;
> (and again, for consistency it should also be done so in
> alloc_l2_table).

Good point


Scott Parish
Signed-off-by: srparish@xxxxxxxxxx

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